Articles tagged as "China"

Exciting biomedical advances – keep your eyes on the longer-term opportunities for HIV prevention and treatment

Editor’s notes: An important advance on the road to effective immune therapies may have been published in the journal Science. We have now entered the era of antibodies for the prevention, and possibly the treatment of HIV.  The AMP study is the first large scale study of antibodies being used to try to prevent HIV infection.  However, most researchers agree that just like antiretroviral therapy, a cocktail of different antibodies is likely to be needed to prevent HIV escaping from immune control, just as it does from individual medicines.  Xu and colleagues at Sanofi have managed to engineer a molecule that is an antibody except that instead of having a single specific target antigen, had three different targets.  In other words, it might function as a cocktail despite being a single agent.  This is important because it might speed up the critical pathway for research.  With multiple antibodies, the regulators naturally want to be certain that each of them is safe and effective before approving trials that combine them.  This can take many years, despite the researchers predicting that the single antibody studies are proofs of concept on the longer pathway to a combination that might make a real difference to treatment or prevention programmes. In studies in macaques, the novel tri-specific antibody molecule provided complete immunity to infection with a range of simian-human immunodeficiency viruses (SHIVs), whereas single antibodies only protected against some of the SHIVs.  This approach to immunotherapy is also an example of HIV science leading to discoveries that might have a much wider field of application in other diseases such as cancer and autoimmune disease.

In addition to making the best antibodies (or T-cell responses), a vaccine also must deliver the antigen or DNA in such a way that the antibodies are made effectively and in high concentrations by the host’s cells.  This is done by means of the vaccine vector.  Previous HIV vaccine candidates have had to be withdrawn from the research pipeline because their vectors appear to have caused harm, possibly by stimulating the immune system in such a way that HIV replication was actually enhanced.  So, the study by Capucci and colleagues is a useful example to show how different vectors work in animal models.  In this study, two vectors that are usually utilized to stimulate T-cell responses were used.  A non-replicating chimpanzee adenovirus or a non-replicating modified vaccinia virus Ankara both produced good antibody responses using an HIV glycoprotein trimer that is known to produce neutralizing antibodies.  The implication might be that these vectors could carry antigens that could provoke useful antibody responses in addition to useful T-cell responses, thus mimicking the most likely way that HIV is controlled in the human host.

Many studies of new biomedical approaches to HIV prevention are tested first in animal models.  Many of us know little of the details of these models.  In order to compare different prevention technologies, it is important that the same or comparable models are used.  Many studies now use simian-human immunodeficiency virus (SHIV).  This is a virus that is genetically modified so that it expresses many aspects of HIV, but still has enough of the SIV components to infect monkeys.  SHIV is often inserted into the vagina of rhesus macaques that have been treated with a new prevention technology or a control to determine whether the technology prevents the establishment of infection.  In the past most macaques used for this research were from India.  However, there is now a shortage of such laboratory monkeys, so Veazey and Ling have done a simple comparison of Indian macaques with Chinese macaques.  With this particular common laboratory strain of SHIV, the authors found no important differences between the two sub-species.

Delving further into the comparative immunology of macaques and humans, Fu and colleagues have performed a comprehensive profiling of lymphocyte receptors from a Chinese macaque.  These sorts of studies allow vaccine scientists to understand how immune responses in macaques can generate antibody and T-cell responses.  They are a building block for future development of vaccines and immune based therapies.  And they remind us how advanced the technology is becoming for ever more detailed understanding of the interactions between primates’ immune systems and the environment to which these systems are exposed.

 

Trispecific broadly neutralizing HIV antibodies mediate potent SHIV protection in macaques

Xu L, Pegu A, Rao E, Doria-Rose N, Beninga J, McKee K, Lord DM, Wei RR, Deng G, Louder M, Schmidt SD, Mankoff Z, Wu L, Asokan M, Beil C, Lange C, Leuschner WD, Kruip J, Sendak R, Do Kwon Y, Zhou T, Chen X, Bailer RT, Wang K, Choe M, Tartaglia LJ, Barouch DH, O'Dell S, Todd JP, Burton DR, Roederer M, Connors M, Koup RA, Kwong PD, Yang ZY, Mascola JR, Nabel GJ. Science. 2017 Oct 6;358(6359):85-90. doi: 10.1126/science.aan8630. Epub 2017 Sep 20.

The development of an effective AIDS vaccine has been challenging because of viral genetic diversity and the difficulty of generating broadly neutralizing antibodies (bnAbs). We engineered trispecific antibodies (Abs) that allow a single molecule to interact with three independent HIV-1 envelope determinants: the CD4 binding site, the membrane-proximal external region (MPER), and the V1V2 glycan site. Trispecific Abs exhibited higher potency and breadth than any previously described single bnAb, showed pharmacokinetics similar to those of human bnAbs, and conferred complete immunity against a mixture of simian-human immunodeficiency viruses (SHIVs) in nonhuman primates, in contrast to single bnAbs. Trispecific Abs thus constitute a platform to engage multiple therapeutic targets through a single protein, and they may be applicable for treatment of diverse diseases, including infections, cancer, and autoimmunity.

Abstract  Full-text [free] access

HIV-1-neutralizing antibody induced by simian adenovirus- and poxvirus MVA-vectored BG505 native-like envelope trimers

Capucci S, Wee EG, Schiffner T, LaBranche CC, Borthwick N, Cupo A, Dodd J, Dean H, Sattentau Q, Montefiori D, Klasse PJ, Sanders RW, Moore JP, Hanke T. PLoS One. 2017 Aug 9;12(8):e0181886. doi: 10.1371/journal.pone.0181886. eCollection 2017.

Rabbits and monkeys immunized with HIV type 1 (HIV-1) native-like BG505 SOSIP.664 (BG505s) glycoprotein trimers are known to induce antibodies that can neutralize the autologous tier-2 virus. Here, we assessed the induction of HIV-1 trimer binding and neutralizing antibody (nAb) titres when BG505s trimers were also delivered by non-replicating simian (chimpanzee) adenovirus and non-replicating poxvirus modified vaccinia virus Ankara (MVA) vaccine vectors. First, we showed that approximately two-thirds and one-third of the trimers secreted from the ChAdOx1.BG505s (C) and MVA.BG505s (M) vaccine-infected cells, respectively, were cleaved and in a native-like conformation. Rabbits were immunized intramuscularly with these vaccine vectors and in some cases boosted with ISCOMATRIX™-adjuvanted BG505s protein trimer (P), using CCC, MMM, PPP, CPP, MPP and CMP vaccine regimens. We found that the peak trimer-binding antibody and tier-1A and autologous tier-2 nAb responses induced by the CC, CM, PPP, CPP, MPP and CMP regimens were comparable, although only PPP induced autologous tier-2 nAbs in all the immunized animals. Three animals developed weak heterologous tier-2 nAbs. These results demonstrate that ChAdOx1 and MVA vectors are useful delivery modalities for not only T-cell, but also antibody vaccine development.

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Comparative susceptibility of rhesus macaques of Indian and Chinese origin to vaginal SHIV transmission as models for HIV prevention research

Veazey R, Ling B. AIDS Res Hum Retroviruses. 2017 Aug 10. doi: 10.1089/AID.2017.0173. [Epub ahead of print]

Historically, Indian origin rhesus macaques (iRM) have been preferred for SIV/HIV prevention, pathogenesis, and treatment studies, yet their supply is limited. Chinese origin rhesus macaques (cRM) are currently more available yet little is known regarding the relative susceptibility of this subspecies to vaginal transmission of SIV or SHIV. Here we compared the susceptibility of 40 cRM and 21 iRM to a single vaginal challenge with SHIVsf162P. Our results showed cRM have comparable primary SHIV infection as iRM, underscoring their equal importance in studies of HIV transmission and prevention.

Abstract access

A comprehensive profiling of T- and B-lymphocyte receptor repertoires from a Chinese-origin rhesus macaque by high-throughput sequencing

Fu L, Li X, Zhang W, Wang C, Wu J, Yang H, Wang J, Liu X. PLoS One. 2017 Aug 16;12(8): e0182733. doi: 10.1371/journal.pone.0182733. eCollection 2017.

Due to the close genetic background, high similarity of physiology, and susceptibility to infectious and metabolic diseases with humans, rhesus macaques have been widely used as an important animal model in biomedical research, especially in the study of vaccine development and human immune-related diseases. In recent years, high-throughput sequencing based immune repertoire sequencing (IR-SEQ) has become a powerful tool to study the dynamic adaptive immune responses. Several previous studies had analyzed the responses of B cells to HIV-1 trimer vaccine or T cell repertoire of rhesus macaques using this technique, however, there are little studies that had performed a comprehensive analysis of immune repertoire of rhesus macaques, including T and B lymphocytes. Here, we did a comprehensive analysis of the T and B cells receptor repertoires of a Chinese rhesus macaque based on the 5'-RACE and IR-SEQ. The detailed analysis includes the distribution of CDR3 length, the composition of amino acids and nucleotides of CDR3, V, J and V-J combination usage, the insertion and deletion length distribution and somatic hypermutation rates of the framework region 3 (FR3). In addition, we found that several positions of FR3 region have high mutation frequencies, which may indicate the existence of new genes/alleles that have not been discovered and/or collected into IMGT reference database. We believe that a comprehensive profiling of immune repertoire of rhesus macaque will facilitate the human immune-related diseases studies.

Abstract  Full-text [free] access

Basic science
Asia, Northern America
China, United States of America
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Technology for tuberculosis, but why can’t we simply prevent it with proven tools that save lives?

Editor’s notes: Advances in diagnostic test technology have transformed the management of HIV and related infections.  For HIV, we have seen the introduction of self-administered test kits as well as new approaches to HIV viral load testing and nucleic acid based infant diagnosis.  Cryptococcal antigen screening can make prophylaxis and treatment more focused and potentially cost-effective.  For tuberculosis the biggest revolution has been the widespread introduction of the geneXpert® system.  The newest version, the Xpert® Ultra, is more sensitive than the original cartridge and is now being scaled up in countries including South Africa.  Agizew and colleagues conducted a study in Botswana to compare how the Xpert® MTB/RIF cartridge performed when used in centralized or peripheral health facilities.  Encouragingly there were few differences between the two levels, suggesting that the systems can be used close to the point of care.  However, the authors did note a surprisingly high level of unsuccessful tests (15%) both at the central lab and at the peripheral clinic.  Many of these test failures seem to have been because the sample was not processed correctly, and so should be amenable to better training for the health care workers performing the test.  The yield of testing varied greatly between the 13 sites. Between 1% and 23% of samples were positive for tuberculosis, with an average of 14%.  This may be because some sites were receiving specialized referrals.  Of the 447 positive samples, 8% were shown to be rifampicin resistant.  This figure is hard to interpret without more detail of the sample of patients in whom the test was performed.  Resistance is always higher among those who have been treated previously and may be higher in those referred to specialized centres.  Nonetheless, it demonstrates that there are a significant number of people with tuberculosis in Botswana who are very likely to have multi-drug resistant disease and need effective second line treatment.  Technology comes with a price tag.  In this study, the team bought test kits for $18 each, which makes it an expensive choice.  However, if it leads to prompt treatment of multi-drug resistant disease and more accurate diagnosis of tuberculosis, including among those living with HIV, this might still be cost-effective.

A small implementation research study from a single provincial referral centre in Zambia also examined the use and results of geneXpert® screening.  Masenga and colleagues found that 6.6% of 2374 samples tested by geneXpert® over the course of a year were positive for tuberculosis.  An additional 1301 samples were tested by sputum microscopy.  Their results suggest that geneXpert® was used mainly on people who were living with HIV, given that more than 90% of the positive samples came from people living with HIV.  5.9% of the 152 positive samples that were tested in the system were resistant to rifampicin, with no difference by gender.  This study leaves many questions unanswered, such as the sampling strategy, the history of previous treatment and the outcomes of the diagnosis in terms of treatment regimen and success.  However, it shines a light on the ways that new technology is now routine in some settings.  We need more research from diverse settings to paint the full picture of implementation outside traditional research centres.

Zenner and colleagues revisit the question of the risks and benefits of treatment for latent tuberculosis infection.  In a systematic review and network meta-analysis, they demonstrate once more that we have several effective ways to prevent tuberculosis among people living with HIV and that the harms are much smaller than the risks.  The question remains why we have failed so badly to scale up preventive therapy for tuberculosis alongside the success in scale up of antiretrovirals.

 

Peripheral clinic versus centralized laboratory-based XPERT® MTB/RIF performance: experience gained from a pragmatic, stepped-wedge trial in Botswana

Agizew T, Boyd R, Ndwapi N, Auld A, Basotli J, Nyirenda S, Tedla Z, Mathoma A, Mathebula U, Lesedi C, Pals S, Date A, Alexander H, Kuebrich T, Finlay A. PLoS One. 2017 Aug 17;12(8):e0183237. doi: 10.1371/journal.pone.0183237. eCollection 2017.

Background: In 2011, the Botswana National Tuberculosis Program adopted World Health Organization guidelines and introduced Xpert® MTB/RIF (Xpert®) assay to support intensified case finding among people living with HIV enrolling in care. An evaluation was designed to assess performance under operational conditions to inform the national Xpert® scale-up.

Methods: Xpert® was implemented from August 2012 through November 2014 with 13 GeneXpert® instruments (GeneXpert®) deployed in a phased approach over nine months: nine centralized laboratory and four point-of-care (POC) peripheral clinics. Clinicians and laboratorians were trained on the four-symptom tuberculosis screening algorithm and Xpert® testing. We documented our experience with staff training and GeneXpert® performance. Test results were extracted from GeneXpert® software; unsuccessful tests were analysed in relation to testing sites and trends over time.

Results: During 276 instrument-months of operation a total of 3630 tests were performed, of which 3102 (85%) were successful with interpretable results. Mycobacterium tuberculosis complex was detected for 447 (14%); of these, 36 (8%) were rifampicin resistant. Of all 3630 Xpert® tests, 528 (15%) were unsuccessful; of these 361 (68%) were classified as "error", 119 (23%) as "invalid" and 48 (9%) as "no result". The total number of recorded error codes was 385 and the most common reasons were related to sample processing (211; 55%) followed by power supply (77; 20%) and cartridge/module related (54; 14%). Cumulative incidence of unsuccessful test was similar between POC (17%, 95% CI: 11-25%) and centralized laboratory-based GeneXpert® instruments (14%, 95% CI: 11-17%; p = 0.140).

Conclusions: Xpert® introduction was successful in the Botswana setting. The incidence of unsuccessful test was similar by GeneXpert® location (POC vs. centralized laboratory). However, unsuccessful test incidence (15%) in our settings was higher than previously reported and was mostly related to improper sample processing. Ensuring adequate training among Xpert® testing staff is essential to minimize errors.

Abstract  Full-text [free] access

Rifampicin resistance in mycobacterium tuberculosis patients using GeneXpert® at Livingstone Central Hospital for the year 2015: a cross sectional explorative study

Masenga SK, Mubila H, Hamooya BM. BMC Infect Dis. 2017 Sep 22;17(1):640. doi: 10.1186/s12879-017-2750-9

Background: Since the recent introduction of GeneXpert® for the detection of Tuberculosis (TB) drug resistance mutations in both primary resistance and acquired resistance in Zambia, little has been documented in literature on the issue of rifampicin resistance especially in the face of a high National TB burden. The study aimed to determine the prevalence of rifampicin resistance in tuberculosis patients at Livingstone Central Hospital for the year 2015.

Methods: This was a cross sectional study conducted at Livingstone Central Hospital where we reviewed 152 records (from January 1, 2015 to 31st December 2015) involving patients who presented with clinically suspected TB or documented TB, whose samples were sent to the laboratory for GeneXpert® Mycobacterium tuberculosis/rifampicin testing. Statistical evaluations used a one-sample test of proportion and Fisher's exact test.

Results: The age of participants ranged from 8 months to 73 years old (median = 34). Of the participants with complete data on gender, 99 (66%) and 52 (34%) were males and females respectively. The TB co-infection with HIV prevalence was 98.3% (p < 0.001). Prevalence of rifampicin resistance was 5.9% and there was no statistical significant difference between being male or female (p = 0.721).

Conclusion: We were able to show from our study, evidence of rifampicin resistance at Livingstone Central Hospital. Hence, there was need for further in-depth research and appropriate interventions (i.e. close follow-up and patient care for drug resistance positive patients).

Abstract  Full-text [free] access

Treatment of latent tuberculosis infection: an updated network meta-analysis

Zenner D, Beer N, Harris RJ, Lipman MC, Stagg HR, van der Werf MJ.  Ann Intern Med. 2017 Aug 15;167(4):248-255. doi: 10.7326/M17-0609. Epub 2017 Aug 1.

Background: Treatment of latent tuberculosis infection (LTBI) is an important component of tuberculosis (TB) control, and this study updates a previous network meta-analysis of the best LTBI treatment options to inform public health action and programmatic management of LTBI.

Purpose: To evaluate the comparative efficacy and harms of LTBI treatment regimens aimed at preventing active TB among adults and children.

Data sources: PubMed, Embase, and Web of Science from indexing to 8 May 2017; clinical trial registries; and conference abstracts. No language restrictions were applied.

Study selection: Randomized controlled trials that evaluated human LTBI treatments and recorded at least 1 of 2 prespecified end points (hepatotoxicity and prevention of active TB).

Data extraction: 2 investigators independently extracted data from eligible studies and assessed study quality according to a standard protocol.

Data synthesis: The network meta-analysis of 8 new and 53 previously included studies showed that isoniazid regimens of 6 months (odds ratio [OR], 0.65 [95% credible interval {CrI}, 0.50 to 0.83]) or 12 to 72 months (OR, 0.50 [CrI, 0.41 to 0.62]), rifampicin-only regimens (OR, 0.41 [CrI, 0.19 to 0.85]), rifampicin-isoniazid regimens of 3 to 4 months (OR, 0.53 [CrI, 0.36 to 0.78]), rifampicin-isoniazid-pyrazinamide regimens (OR, 0.35 [CrI, 0.19 to 0.61]), and rifampicin-pyrazinamide regimens (OR, 0.53 [CrI, 0.33 to 0.84]) were efficacious compared with placebo. Evidence existed for efficacy of weekly rifapentine-isoniazid regimens compared with no treatment (OR, 0.36 [CrI, 0.18 to 0.73]). No conclusive evidence showed that HIV status altered treatment efficacy.

Limitation: Evidence was sparse for many comparisons and hepatotoxicity outcomes, and risk of bias was high or unknown for many studies.

Conclusion: Evidence exists for the efficacy and safety of 6-month isoniazid monotherapy, rifampicin monotherapy, and combination therapies with 3 to 4 months of isoniazid and rifampicin.

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HIV testing and the HIV epidemic –vitally important to prevent HIV becoming endemic

Editor’s notes: Epidemics refer to situations where the number of infections rises (and subsequently falls) more quickly than might be expected compared to a disease that is endemic.  Endemic implies a stable situation, with natural fluctuations in the number of cases.  Medley and Vassal have written a provocative article in Science that considers how differently individuals, communities and society react to epidemic rather than endemic diseases.  They choose to call HIV in 2017 endemic, which carries a serious risk. As the authors state, “The contained public response, and the concurrent shift of responsibility to individuals to protect themselves from risk, means that endemic disease embeds itself further, as those at risk are often the very same people who do not have the private resources to avoid risk or access treatment.”  There are in fact multiple separate epidemics of HIV in different regions and in different populations.  Some are rising and some are falling. The latest UNAIDS’ report emphasizes the heterogeneity of HIV infections in the world.  New HIV infections have fallen by 29% since 2010 in East and Southern Africa, the region with the highest rates.  On the other hand, new HIV infections have risen by an alarming 60% in Eastern Europe and Central Asia over the same period, albeit from a much lower baseline.  There is widespread political consensus to pursue the UN agenda endorsed at the High Level Meeting on Ending AIDS in New York last year.  Let’s not throw in the towel too soon!

HIV testing services remain central to the HIV strategy and, as usual, this month there are several important papers on aspects of HIV testing, many of which illustrate challenges that need to be overcome.

There are several reasons to encourage people living with HIV to know their status.  First and foremost, we know that the earlier treatment is started in the course of HIV, the better the outlook for the individual.  People who start treatment become much less likely to transmit HIV infection to sexual partners. People who know their HIV status are also able to make informed decisions about their lives and their partnerships.  A study this month by Escudero et al. from New York City used agent-based modelling to understand the testing and care continuum for people who inject drugs. Their results remind us of the key role of HIV testing.  They estimated that 53% of the HIV transmission events from people who inject drugs arose from people who did not know their status, and a further 37% from people who had not been started ART.  In other words, they estimate that only 10-11% of infections from people who inject drugs could be prevented by improving quality of care for people on treatment.  The need to find effective ways to encourage people at risk to know their status and start treatment is stark.

Guanzhou is one of the largest cities in China, with a high population of migrants both national and international.  It is among the most prosperous regions of Guangdong province and has the highest rates of HIV.   Chen et al. added some HIV testing related questions to a wider population based health survey in two districts and showed that approximately a quarter of adults had previously been tested for HIV.  HIV testing was almost all provided through free government facilities or blood transfusion centres.  Despite early steps to make HIV self-testing more available, none of the 666 participants who answered the relevant questions in the survey had used a self-test.  Distance from an HIV testing site was a key determinant of the likelihood of getting tested.  It was not clear that people who might be at higher risk were more likely to be tested, although the numbers and sampling focused on the general population rather than people at special risk.

Wang et al. explored the different HIV test kits used in the first line screening in Xi’an.  In line with Chinese guidelines, but not in line with WHO guidance on HIV testing algorithms for low prevalence settings, they used third- or fourth-generation rapid tests and repeated the positive tests.  WHO’s algorithm for low prevalence settings includes three different rapid tests based on different antigens.   Among 665 people found to be positive on rapid tests, only 559 were confirmed to be HIV-positive by Western blotting.  Subsequent follow up with additional Western blots showed that two of the individuals in whom the first Western blot was indeterminate were seroconverting but the other 104 were HIV-negative and had had false-positive results on the original rapid tests.  False positives were more likely with the fourth-generation test (22% of positive tests) compared to the various third-generation tests used (9-11% of positive tests).  Fourth-generation assays are known to be more sensitive, detecting people with HIV around a week or two earlier in the window period than third-generation assays.  However, the authors point out that in low prevalence settings like Xi’an, the known lack of specificity of fourth-generation assays means that they may not provide sufficient advantages to be used as the first line test.  Overall, the paper emphasizes the importance of using clearly defined algorithms.  The WHO algorithms no longer use Western blots, but do recommend using multiple tests based on different antigens for testing people at low risk of infection, and at least two different tests with different antigens for testing people at high risk of infection.  Everyone should have additional confirmatory tests done prior to starting ART.

Harbertson et al. also focused on the accuracy of rapid diagnostic tests.  They screened samples from 459 military personnel in seven African countries who had reported that they were HIV-positive.  Using the WHO algorithm, they compared the results of quality assured HIV testing to the self-reported HIV status of the participants.  They found that, in different country surveys, between three and 91% of people who said that they were living with HIV were in fact HIV-negative.  The authors point out that several studies have demonstrated the importance of following the WHO guidance, and that the positive predictive value of a test (or algorithm) will always fall as the overall prevalence falls.  They discuss possible limitations such as misunderstanding the question or the terminology used, but discount these possibilities as causing many of the false-positive reports, particularly given the highly variable results across different countries.  There was a strong association between the likelihood of a false positive report and lower education level. People whose understanding of HIV was less good were also more likely to report themselves to be positive falsely.  Overall, the authors assume that quality of testing services needs to be an important priority, while not discounting the challenges of using self-reports to collect information about HIV status.

As more and more people chose to know their HIV status, it may be possible to use routine data from the health service to track the epidemiology of HIV, rather than to use special surveys. Traditionally surveys of antenatal mothers have been used to monitor trends in the HIV epidemic over time.  With the widespread adoption of routine testing for mothers, a large proportion of women have an HIV test.  However, the assays used vary.  For surveillance purposes, samples are often stored and transported as dried blood spots and assays are run in batches using automated ELISA technology.  Routine testing (as discussed above) is often done using an algorithm based on a number of different rapid tests.   Pereira et al. have explored the differences between these approaches among almost 40 000 Brazilian mothers who participated in the antenatal surveillance exercise.  They interviewed mothers and linked their routine ANC results to the surveillance database.  Overall the prevalence of HIV among expectant mothers in Brazil was similar whichever approach was used (0.36% or 0.38%).  However, there were interesting differences.  The performance accuracy in those found positive in the surveillance exercise (which was taken as the gold standard) was only 84% overall and varied between regions from 43% to 100%.  So these 14 false negative results among the 88 individuals who were truly positive were compensated for in the overall prevalence estimates by a similar number (18) of false positive results among around 30 000 individuals who were truly negative. This highlights the challenges of providing accurate results to people in low prevalence settings. The 13% of mothers who slipped through the routine services and were not tested or refused to be tested were significantly more likely to be HIV-positive (0.56%), reinforcing the potential biases involved.  Finding 90% of people living with HIV will require considerable attention to the detail and the quality of HIV testing services.

Adolescents are often a population left behind, and regular reports show that adolescents living with HIV are less likely to know their status or to be on treatment or virally supressed.  Simms et al. used provider initiated testing and counselling (PITC) in primary care clinics in Harare, Zimbabwe.  For two years, the research team supported the routine offer of HIV testing to all six to 15 year olds presenting to seven clinics in a well-defined area of Harare.  The authors then conducted a population-based survey to find out how many eight to 17 year olds (who had had two years of exposure to the intervention) were aware of their status. 141 (2.6%) were living with HIV and more than one-third of these were undiagnosed.  Some had rarely been to the clinic, and others had been taken to the clinic by a guardian who was unable to consent to HIV testing on behalf of the child or the child’s parents.  Others had slipped through the PITC net, possibly because, as Lightfoot et al. in an accompanying comment suggest, providers still find it hard to offer HIV tests to everyone, as they assume that people living with HIV will not appear healthy.  This fits with the researchers’ findings that adolescents living with HIV who were currently healthy, had no skin or other problems and had parents who were alive were less likely to be diagnosed.  Both papers suggest that community based testing is needed to find adolescents. However, this also raises challenges in settings with lower prevalence than the high-density suburbs of Harare chosen for this project.  As prevalence falls lower than the 2.6% observed, a huge testing effort is needed, with attendant costs, but also (as explored above) with the risks of inaccurate results and of the very people that we want to find most, not being around for testing at the right moment. 

 

When an emerging disease becomes endemic.

Medley GF, Vassall A. Science. 2017 Jul 14;357(6347):156-158. doi: 10.1126/science.aam8333.

Epidemics, such as HIV in the early 1980s and Ebola in 2014, inspire decisive government investment and action, and individual and societal concern, sometimes bordering on panic. By contrast, endemic diseases, such as HIV in 2017 and tuberculosis, struggle to maintain the same attention. For many, the paradox is that endemic disease, in its totality, continues to impose a far higher public health burden than epidemic disease. Overall, the swift political response to epidemics has resulted in success. It has proven possible to eradicate epidemic diseases, often without the availability of vaccines and other biomedical technologies. In recent times, only HIV has made the transition from epidemic to endemic, but diseases that have existed for centuries continue to cause most of the infectious disease burden.

Abstract access

 

The risk of HIV transmission at each step of the HIV care continuum among people who inject drugs: a modeling study.

Escudero DJ, Lurie MN, Mayer KH, King M, Galea S, Friedman SR, Marshall BL. BMC Public Health. 2017 Jul 25;17(1):614. doi: 10.1186/s12889-017-4528-9.

Background: People who inject drugs (PWID) are at continued risk for HIV in the U.S., and experience disparities across the HIV care continuum compared to other high-risk groups. Estimates of the risk of HIV transmission at each stage of the care continuum may assist in identifying public health priorities for averting incident infections among PWID, in addition to transmissions to sexual partners of PWID.

Methods: We created an agent-based model simulating HIV transmission and the HIV care continuum for PWID in New York City (NYC) in 2012. To account for sexual transmission arising from PWID to non-PWID, the simulation included the entire adult NYC population. Using surveillance data and estimates from the National HIV Behavioral Surveillance system, we simulated a dynamic sexual and injecting network. We estimated the proportion of HIV transmission events attributable to PWID in the following categories, those: without an HIV diagnosis ('Undiagnosed'); diagnosed but not on antiretroviral therapy (ART) ('Diagnosed - not on ART'); those who initiated ART but were not virally suppressed ('Unsuppressed'); and, those who achieved viral suppression ('Suppressed').

Results: We estimated HIV incidence among PWID to be 113 per 100 000 person-years in 2012, with an overall incidence rate for the entire adult NYC population of 33 per 100 000 person-years. Despite accounting for only 33% of the HIV-infected PWID population, the Undiagnosed were associated with 52.6% (95% simulation interval [95% SI]: 47.1-57.0%) of total transmission events. The Diagnosed - not on ART population contributed the second-largest proportion of HIV transmissions, with 36.6% (95% SI: 32.2-41.5%). The Unsuppressed population contributed 8.7% (95% SI: 5.6-11.8%), and Suppressed 2.1% (95% SI: 1.1-3.9%), relatively little of overall transmission.

Conclusion: Among PWID in NYC, more than half (53%) of transmissions were from those who were unaware of their infection status and more than 36% were due to PWID who knew their status, but were not on treatment. Our results indicate the importance of early diagnosis and interventions to engage diagnosed PWID on treatment to further suppress population-level HIV transmission. Future HIV prevention research should focus on the elimination of identified and potential barriers to the testing, diagnosis, and retention of PWID on HIV treatment.

Abstract  Full-text [free] access

 

Is there a relationship between geographic distance and uptake of HIV testing services? A representative population-based study of Chinese adults in Guangzhou, China.

Chen W, Zhou F, Hall BJ, Tucker JD, Latkin C, Renzaho AMN, Ling L. PLoS One. 2017 Jul 20;12(7):e0180801. doi: 10.1371/journal.pone.0180801. eCollection 2017.

Achieving high coverage of HIV testing services is critical in many health systems, especially where HIV testing services remain centralized and inconvenient for many. As a result, planning the optimal spatial distribution of HIV testing sites is increasingly important. We aimed to assess the relationship between geographic distance and uptake of HIV testing services among the general population in Guangzhou, China. Utilizing spatial epidemiological methods and stratified household random sampling, we studied 666 adults aged 18-59. Computer-assisted interviews assessed self-reported HIV testing history. Spatial scan statistic assessed the clustering of participants who have ever been tested for HIV, and two-level logistic regression models assessed the association between uptake of HIV testing and the mean driving distance from the participant's residence to all HIV testing sites in the research sites. The percentage of participants who have ever been tested for HIV was 25.2% (168/666, 95%CI: 21.9%, 28.5%), and the majority (82.7%) of participants tested for HIV in Centres for Disease Control and Prevention, public hospitals or STIs clinics. None reported using self-testing. Spatial clustering analyses found a hotspot included 48 participants who have ever been tested for HIV and 25.8 expected cases (Rate Ratio = 1.86, P = 0.002). Adjusted two-level logistic regression found an inverse relationship between geographic distance (kilometers) and ever being tested for HIV (aOR = 0.90, 95%CI: 0.84, 0.96). Married or cohabiting participants (aOR = 2.14, 95%CI: 1.09, 4.20) and those with greater social support (aOR = 1.04, 95%CI: 1.01, 1.07) were more likely to be tested for HIV. Our findings underscore the importance of considering the geographical distribution of HIV testing sites to increase testing. In addition, expanding HIV testing coverage by introducing non-facility based HIV testing services and self-testing might be useful to achieve the goal that 90% of people living with HIV knowing their HIV status by the year 2020.

Abstract  Full-text [free] access

 

The characteristics of screening and confirmatory test results for HIV in Xi'an, China.

Wang L, Zhou KH, Zhao HP, Wang JH, Zheng HC, Yu Y, Chen W. PLoS One. 2017 Jul 7;12(7):e0180071. doi: 10.1371/journal.pone.0180071. eCollection 2017.

Objectives: Individuals with recent or acute HIV infection are more infectious than those with established infection. Our objective was to analyze the characteristics of detection among HIV infections in Xi'an.

Methods: A 4th-generation kit (Architect HIV Ag/Ab Combo) and three 3rd-generationEIA kits (WanTai, XinChuang and Livzon) were used for HIV screening. Overall, 665 individuals were identified as positive and were tested by western blotting (WB). The characteristics of the screening and confirmatory tests were analyzed, including the band patterns, the early detection performance and the false-positive rates.

Results: In total, 561 of the 665 patients were confirmed as having HIV-1 infection, and no HIV-2 specific band was observed. Among these 561 WB-positive cases, reactivity to greater than or equal to 9 antigens was the most commonly observed pattern (83.18%), and the absence of reactivity to p17, p31 and gp41 was detected in 6.44%, 5.9% and 2.86% of the cases, respectively. Two cases were positive by the 4th-generation assay but negative by the 3rd-generation assay for HIV screening and had seroconversion. The false-positive rate of the Architect HIV Ag/Ab Combo (22.01%) was significantly higher than those of WanTai (9.88%), XinChuang (10.87%) and Livzon (8.93%), p<0.05

Conclusion: HIV infection in Xi'an is mainly caused by HIV-1, and individuals are rarely identified at the early phase. Although the false-positive rate of the 4th-generation assay was higher than that of the 3rd-generation assay, it is still recommended for use as the initial HIV screening test for high-risk individuals. In Xi'an, a 3rd-generation assay for screening could be considered.

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Self-reported HIV-positive status but subsequent HIV-negative test result using rapid diagnostic testing algorithms among seven sub-Saharan African military populations.

Harbertson J, Hale BR, Tran BR, Thomas AG, Grillo M, Jacobs MB, McAnany J, Shaffer RA. PLoS One. 2017 Jul 7;12(7):e0180796. doi: 10.1371/journal.pone.0180796. eCollection 2017.

HIV rapid diagnostic tests (RDTs) combined in an algorithm are the current standard for HIV diagnosis in many sub-Saharan African countries, and extensive laboratory testing has confirmed HIV RDTs have excellent sensitivity and specificity. However, false-positive RDT algorithm results have been reported due to a variety of factors, such as suboptimal quality assurance procedures and inaccurate interpretation of results. We conducted HIV serosurveys in seven sub-Saharan African military populations and recorded the frequency of personnel self-reporting HIV positivity, but subsequently testing HIV-negative during the serosurvey. The frequency of individuals who reported they were HIV-positive but subsequently tested HIV-negative using RDT algorithms ranged from 3.3 to 91.1%, suggesting significant rates of prior false-positive HIV RDT algorithm results, which should be confirmed using biological testing across time in future studies. Simple measures could substantially reduce false-positive results, such as greater adherence to quality assurance guidelines and prevalence-specific HIV testing algorithms as described in the World Health Organization's HIV testing guidelines. Other measures to improve RDT algorithm specificity include classifying individuals with weakly positive test lines as HIV indeterminate and retesting. While expansion of HIV testing in resource-limited countries is critical to identifying HIV-infected individuals for appropriate care and treatment, careful attention to potential causes of false HIV-positive results are needed to prevent the significant medical, psychological, and fiscal costs resulting from individuals receiving a false-positive HIV diagnosis.

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Transitioning from antenatal surveillance surveys to routine HIV testing: a turning point in the mother-to-child transmission prevention programme for HIV surveillance in Brazil.

Pereira GFM, Sabidó M, Caruso A, Benzaken AS. BMC Infect Dis. 2017 Jul 5;17(1):469. doi: 10.1186/s12879-017-2540-4.

Background: In Brazil, due to the rapid increase in programmes for the prevention of mother-to-child transmission (PMTCT), routine programme data are widely available. The objective of this study was to assess the utility of programmatic data to replace HIV surveillance based on the antenatal care (ANC) surveillance survey (SS).

Methods: We analysed ANC SS data from 219 maternity service clinics. PMTCT variables were extracted from the ANC SS data collection form, which allowed us to capture and compare the ANC SS data and PMTCT HIV test results for each pregnant woman who completed the ANC SS. Both the PMTCT programme and the ANC SS tested for HIV using sequential ELISA and western blot for confirmation. We assessed the completeness (% missing) of the PMTC data included in the ANC SS.

Results: Of the 36 713 pregnant women who had ANC SS HIV tests performed, 30 588 also underwent PMTCT HIV testing. The HIV prevalence rate from routine PMTCT testing was 0.36%, compared to 0.38% from the ANC SS testing (relative difference -0.05%; absolute difference -0.02%). The relative difference in prevalence rates between pregnant women in northern Brazil and pregnant women central-west Brazil was -0.98 and 0.66, respectively. Of the 29 856 women who had HIV test results from both the PMTCT and ANC SS, the positive percent agreement of the PMTCT versus the surveillance test was 84.1% (95% confidence interval [CI]: 74.8-91.0), and the negative percent agreement was 99.9% (95% CI: 99.9-100.0). The PMTCT HIV testing uptake was 86.4%. The ANC SS HIV prevalence was 0.33% among PMTCT non-refusers and 0.59% among refusers, with a percent bias of -10.80% and a differential prevalence ratio of 0.56. Syphilis and HIV testing results were complete in 98% and 97.6% of PMTCT reports, respectively. The reported HIV status for the women at clinic entry was missing.

Conclusion: Although there were consistent HIV prevalence estimates from the PMTCT data and the ANC SS, the overall positive percent agreement of 84.1% falls below the World Health Organization benchmark of 94.7%. Therefore, Brazil must continue to reinforce data collection practices and ensure the quality of recently introduced rapid HIV testing before replacing the PMTCT data with surveillance techniques. However, some regions with better results could be prioritized to pilot the use of PMTCT data for surveillance.

Abstract  Full-text [free] access

 

Community burden of undiagnosed HIV infection among adolescents in Zimbabwe following primary healthcare-based provider-initiated HIV testing and counselling: A cross-sectional survey.

Simms V, Dauya E, Dakshina S, Bandason T, McHugh G, Munyati S, Chonzi P, Kranzer K, Ncube G, Masimirembwa C, Thelingwani R, Apollo T, Hayes R, Weiss HA, Ferrand RA. PLoS Med. 2017 Jul 25;14(7):e1002360. doi: 10.1371/journal.pmed.1002360. eCollection 2017 Jul.

Background: Children living with HIV who are not diagnosed in infancy often remain undiagnosed until they present with advanced disease. Provider-initiated testing and counselling (PITC) in health facilities is recommended for high-HIV-prevalence settings, but it is unclear whether this approach is sufficient to achieve universal coverage of HIV testing. We aimed to investigate the change in community burden of undiagnosed HIV infection among older children and adolescents following implementation of PITC in Harare, Zimbabwe.

Methods and Findings: Over the course of 2 years (January 2013-January 2015), 7 primary health clinics (PHCs) in southwestern Harare implemented optimised, opt-out PITC for all attendees aged 6-15 years. In February 2015-December 2015, we conducted a representative cross-sectional survey of 8-17-year-olds living in the 7 communities served by the study PHCs, who would have had 2 years of exposure to PITC. Knowledge of HIV status was ascertained through a caregiver questionnaire, and anonymised HIV testing was carried out using oral mucosal transudate (OMT) tests. After 1 participant taking antiretroviral therapy was observed to have a false negative OMT result, from July 2015 urine samples were obtained from all participants providing OMTs and tested for antiretroviral drugs to confirm HIV status. Children who tested positive through PITC were identified from among survey participants using gender, birthdate, and location. Of 7146 children in 4251 eligible households, 5486 (76.8%) children in 3397 households agreed to participate in the survey, and 141 were HIV positive. HIV prevalence was 2.6% (95% CI 2.2%-3.1%), and over a third of participants with HIV were undiagnosed (37.7%; 95% CI 29.8%-46.2%). Similarly, among the subsample of 2643 (48.2%) participants with a urine test result, 34.7% of those living with HIV were undiagnosed (95% CI 23.5%-47.9%). Based on extrapolation from the survey sample to the community, we estimated that PITC over 2 years identified between 18% and 42% of previously undiagnosed children in the community. The main limitation is that prevalence of undiagnosed HIV was defined using a combination of 3 measures (OMT, self-report, and urine test), none of which were perfect.

Conclusions: Facility-based approaches are inadequate in achieving universal coverage of HIV testing among older children and adolescents. Alternative, community-based approaches are required to meet the Joint United Nations Programme on HIV/AIDS (UNAIDS) target of diagnosing 90% of those living with HIV by 2020 in this age group.

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How are we going to get to our prevention targets? Old tools, new tools and a more nuanced understanding of transmission dynamics.

Editor’s notes: By 2020, the Fast-Track strategy is aiming to reduce new HIV infections to 200 000 per year.  There is increasing recognition that if we are to succeed, we will need to do much more than simply putting people onto HIV treatment.  Despite the massive impact of ART on infectiousness, the decline in new infections at the community level is still not fast enough, even in countries like Botswana (see above) where 90-90-90 has almost been reached.  Renewed enthusiasm for primary prevention has also followed key trials of biomedical prevention tools including voluntary medical male circumcision and ARV-based prevention.  It is all too easy for us to forget the crucial role that condoms have played from the early days of the epidemic.  More recently, with HIV seen as a less terrifying infection, many programmes suffer from “condom fatigue”.  So it is good to see papers on the key importance of condoms as well as perspectives on how they are perceived by young men.

The magic of ARVs does not end with treatment.  We are finally moving to wider use of pre-exposure prophylaxis (PrEP).  There is no doubt that PrEP works when taken, but there are still plenty of questions for policy-makers about how to adopt it whole-heartedly into their national strategic plans and for financiers about how to pay for it.  Papers this month cover a range of experiences with PrEP from the US, where the huge majority of PrEP users still live, to Europe and Australia, where policies are finally moving towards wider use.  Long acting PrEP remains a key objective for many, as it might improve regular adherence, which has proved the Achilles’ heel of oral and topical PrEP in several of the large studies.

One of the ways to make PrEP most cost-effective is to ensure that it is available to people who are most likely to acquire HIV.  So the hope continues that phylogenetic analyses will allow more sophisticated understanding of the dynamics of the multiple overlapping networks of HIV transmission in communities.  Papers this month cover Australia and the PANGEA consortium of African research sites along with a cautionary comment about establishing the ethical framework for such studies, particularly among populations who are already subject to discrimination and criminalization.

When used correctly and consistently, condoms are highly effective not only to prevent HIV but also to prevent pregnancy and to prevent sexually transmitted infections.  Stover and colleagues have tried to capture all three benefits in one model.  They explore three potential scenarios for condom programming between now and 2030 in 81 countries that are priorities for family planning or HIV programmers or both.  The benefits of greater investment in condoms are huge.  In their most optimistic scenario, the authors suggest that if the entire gap between people who would like to use condoms and people who currently use them was filled (almost 11 billion condoms over the period), this could prevent up to 400 million unwanted pregnancies; 16.8 million new HIV infections and more than 700 million sexually transmitted infections.  The costs are quite modest, and at $115 per DALY averted this is an investment that everyone should support.  There are of course limitations in such a broad brush model, but it provides an excellent starting point.

The challenges in provision of condoms to young people go well beyond the cost and effectiveness considerations that underpin the previous analysis.  In an interesting qualitative study in South Africa, de Bruin and Panday-Soobrayan report their findings from focus group discussions with learners in 33 public schools.  Most of the learners were not in favour of provision of condoms at school, although they were keen on more youth friendly sexual and reproductive health and rights services within the public sector.  Many thought that provision of condoms would lead to earlier and more frequent sexual contacts, despite considerable experience showing that this is not the case in other settings.

Multiple trials have shown that PrEP is extremely effective when it is used consistently and correctly.  Many countries in all continents are now beginning to work out where it fits within their combination prevention package.  To date, the large majority of PrEP users are in the United States of America (USA), where more than 140 000 people have started.  It is much harder to measure how many are still taking it regularly.  Patel and colleagues analysed utilization at three months after the initial prescription of PrEP in three major PrEP clinics in three states in the USA.  18% of the 201 people (90% male) seen at baseline did not use their PrEP and this was strongly predicted by insurance status, with around a four-fold risk of dropping out among those who were not insured.  Although the numbers are small, this is an important study.  The authors suggest that increased insurance cover might make PrEP have a greater impact.  More broadly it raises the challenge that PrEP is often needed most by people least able to access it.  This will be a real challenge in countries where people most at risk, such as gay men and other men who have sex with men and sex workers, are criminalized or discriminated against in many health care settings.

In Australia, PrEP has been provided through large demonstration projects while awaiting decisions about how to include it in routine practice.  Lal and colleagues report results from 114 (one transgender woman, the rest male) people taking PrEP in the Victorian PrEP Demonstration project.  Participants have to pay an equivalent of an insurance co-payment, in order to make the situation more like the “real world”.  The participants were recruited because they were at high risk of HIV engaging in condomless anal sex with partners who were known to be living with HIV or of unknown status.  Adherence to PrEP was excellent as measured by a variety of reported and biological measures.  They observed one seroconversion in a man with exposure two weeks before starting PrEP who was already in the process of seroconverting and whose virus was found to be resistant to emtricitabine.  The only other seroconversion occurred in someone who had not yet started PrEP.  The authors found a substantial increase in rates of gonorrhoea and chlamydia once participants were “stable” on PrEP after three months.  There was also a significant reduction in condom use with both regular and casual partners.  This is one of the first studies to document important risk compensation among PrEP users.  Of course, preventing HIV is a huge benefit that generally outweighs the harms of additional treatment for sexually transmitted infections.  However, the study emphasizes the importance of enhancing sexual health services alongside PrEP and reminds us that people most at risk of HIV are also at high risk of other infections (and also of pregnancy in the context of heterosexual transmission.)  If PrEP is integrated within a broad sexual health service, there could be considerable synergistic benefits.

Gay men and men who have sex with men who enrolled in the PrEP demonstration project in Amsterdam also had high concomitant rates of hepatitis C virus (HCV).  Hoorenborg and colleagues found that around 5% of the 375 men enrolled in the project were co-infected.  The HCV found among these men were genetically similar to those circulating in the population of gay men and other men who have sex with men living with HIV, and more distinct from HCV from other risk groups.  This is good evidence that HCV and HIV both circulate in this population, and emphasizes once again the need for more integrated services, including hepatitis screening.

The ÉCLAIR study is a phase 2a trial of cabotegravir injections in healthy HIV-negative male volunteers.  As noted, adherence is a major challenge in many PrEP trials; although notably less of a problem when people choose to take PrEP in demonstration projects.  It is hoped that cabotegravir could be the first long acting PrEP.  Markowitz and colleagues presented the results of this study at CROI 2017.  The authors point out that although the injections are painful, many men stated that they would be happy to continue if the injections were effective.  No serious safety challenges emerged. The pharmacokinetics suggests that a dose given more frequently will be needed – and subsequent trials will use a two monthly regimen. 

One group for whom PrEP has been recommended by WHO for some years are serodiscordant couples (SDCs).  The Partners PrEP study, which forms one of the cornerstones for the evidence that PrEP works for both men and women, was conducted in SDCs.  The idea is to protect the HIV-negative partner from infection until such time as the partner living with HIV has been on ART consistently and suppressed their viral load.  So a study from the Centers for Disease Control USA is relevant to discussions of PrEP.  Crepaz and colleagues found that around 6000 new HIV infections occur each year in the USA among men and women having heterosexual sex and are aware that their partner is living with HIV.  They point out that viral suppression is achieved by only around 50% of heterosexuals living with HIV and that an additional proportion does not know their HIV status.  So the importance of HIV testing, and of focusing efforts on serodiscordant couples is clear.  Such efforts include both improving HIV treatment effectiveness, and providing a range of prevention choices including PrEP until viral suppression is achieved.

While the study above used traditional epidemiological surveillance reports, phylogenetics may provide additional insights into the dynamics of transmission.  In Australia, where notifications with HIV are rising steadily,  Castley and colleagues have examined the sequence data from almost 5000 viruses collected across the country from 2005-2012.  This sample is drawn from around 1200 new HIV infections per year (and around 27 000 people living with HIV).  The sample is not random, but reflects samples that were sent for sequencing to determine drug resistance.  Around one quarter of sequences are found in tight clusters (pairs, triplets or more) with other sequences, making it likely that they are closely connected by transmission.  Of course, all HIV sequences have been transmitted, so a longer time period and complete sampling would be expected to give a much higher proportion in clusters.  Indeed the more recent samples are around twice as likely to be in clusters as those collected at the start of the time period. Nonetheless, the large sample and the time period of collection allows some clear observations to be made.  In all states, the proportion of non-B subtypes is increasing, which must relate to travel and migration to and from Asia and Africa.  There is little evidence that the C subtypes (originally from Africa) are found in all male clusters suggesting little spill over into the community of gay men and other men having sex with men.  Larger clusters are more common among younger, all male networks. Like most molecular epidemiological studies, there are a small number of large clusters which represent highly active transmission.  These clusters are also most likely to be all male.  Taken together, the results suggest that the steady rise in notifications in Australia is probably due to increasing migration and travel and to ongoing active transmission networks among young gay men.  The challenge is to turn this sort of analysis into clear policy recommendations that can improve HIV prevention.

UNAIDS joined an interesting meeting on the ethics of phylogenetic studies in Africa organised by the PANGEA consortium.  Many of the issues discussed are also covered in a comment by Cohen on the importance of thinking through the risks inherent in these studies.  A key issue is to ensure that systems are reinforced to monitor any unexpected harms and to establish mitigation strategies to minimize them.  The challenges are not necessarily different to traditional epidemiological studies which may highlight networks and locations of groups that are criminalized or discriminated against.  In community consultations, prior to agreeing to go forward with phylogenetic studies, some potential participants even say that they would be keen to “know who infected them” in order to punish them.  This is clearly NOT the aim of such studies and emphasizes the importance of clear information about the limitations of the techniques which cannot usually rule out the possibility of additional links in the transmission chain.  Issues of anonymised information and what to do if clinically relevant results such as drug resistance mutations are uncovered as incidental findings also need to be discussed.

Furthermore, Ratmann and colleagues, reporting on the first 4000 sequences from the PANGEA consortium (largely from the Rakai project in Uganda), also emphasize some of the technical challenges that may lead to erroneous results in creating phylogenies.  There is little doubt that as the cost of sequencing falls and as the technologies and software become increasingly straightforward, we will see more and more studies of sequence data.  It is likely that analysis of these data will lead to more nuanced approaches to HIV prevention, particularly as the overall incidence falls, and sharper tools are needed to dissect the pathways of ongoing transmission.

The case for investing in the male condom

Stover J, Rosen JE, Carvalho MN, Korenromp EL, Friedman HS, Cogan M, Deperthes B. PLoS One. 2017 May 16;12(5):e0177108. doi: 10.1371/journal.pone.0177108. eCollection 2017.

When used correctly and consistently, the male condom offers triple protection from unintended pregnancy and the transmission of sexually transmitted infections (STIs) and human immunodeficiency virus (HIV). However, with health funding levels stagnant or falling, it is important to understand the cost and health impact associated with prevention technologies. This study is one of the first to attempt to quantify the cost and combined health impact of condom use, as a means to prevent unwanted pregnancy and to prevent transmission of STIs including HIV. This paper describes the analysis to make the case for investment in the male condom, including the cost, impact and cost-effectiveness by three scenarios (low in which 2015 condom use levels are maintained; medium in which condom use trends are used to predict condom use from 2016-2030; and high in which condom use is scaled up, as part of a package of contraceptives, to meet all unmet need for family planning by 2030 and to 90% for HIV and STI prevention by 2016) for 81 countries from 2015-2030. An annual gap between current and desired use of 10.9 billion condoms was identified (4.6 billion for family planning and 6.3 billion for HIV and STIs). Under a high scenario that completely reduces that gap between current and desired use of 10.9 billion condoms, we found that by 2030 countries could avert 240 million DALYs. The additional cost in the 81 countries through 2030 under the medium scenario is $1.9 billion, and $27.5 billion under the high scenario. Through 2030, the cost-effectiveness ratios are $304 per DALY averted for the medium and $115 per DALY averted for the high scenario. Under the three scenarios described above, our analysis demonstrates the cost-effectiveness of the male condom in preventing unintended pregnancy and HIV and STI new infections. Policy makers should increase budgets for condom programming to increase the health return on investment of scarce resources.

Abstract  Full-text [free] access

Learners' perspectives on the provision of condoms in South African public schools.

de Bruin WE, Panday-Soobrayan S. AIDS care. 2017 May 16:1-4. doi: 10.1080/09540121.2017.1327647. [Epub ahead of print]

A stubborn health challenge for learners in South African public schools concerns sexual and reproductive health and rights (SRHR). In 2015, the Department of Basic Education (DBE) proposed the provision of condoms and SRHR-services to learners in schools. This study aimed to contribute to the finalisation and implementation of DBE's policy by exploring learners' perspectives on the provision of condoms and SRHR-services in schools. Sixteen focus group discussions were conducted with learners (n = 116) from 33 public schools, to assess their attitudes, social influences, and needs and desires regarding condom provision and SRHR-services in schools. The majority of learners did not support condom provision in schools as they feared that it may increase sexual activity. Contrarily, they supported the provision of other SRHR-services as clinics fail to offer youth-friendly services. Learners' sexual behaviour and access to SRHR-services are strongly determined by their social environment, including traditional norms and values, and social-pressure from peers and adults. Learners' most pressing needs and desires to access condoms and SRHR-services in school concerned respect, privacy and confidentiality of such service provision. Implementation of DBE's policy must be preceded by an evidence-informed advocacy campaign to debunk myths about the risk of increased sexual activity, to advocate for why such services are needed, to shift societal norms towards open discussion of adolescent SRHR and to grapple with the juxtaposition of being legally empowered but socially inhibited to protect oneself from HIV, STIs and early pregnancy. Provision of condoms and other SRHR-services in schools must be sensitive to learners' privacy and confidentiality to minimise stigma and discrimination.

Abstract  Full-text [free] access

Impact of insurance coverage on utilization of pre-exposure prophylaxis for HIV prevention

Patel RR, Mena L, Nunn A, McBride T, Harrison LC, Oldenburg CE, Liu J, Mayer KH, Chan PA.  PLoS One. 2017 May 30;12(5):e0178737 . doi: 10.1371/journal.pone.0178737. eCollection 2017.

Pre-exposure prophylaxis (PrEP) can reduce U.S. HIV incidence. We assessed insurance coverage and its association with PrEP utilization. We reviewed patient data at three PrEP clinics (Jackson, Mississippi; St. Louis, Missouri; Providence, Rhode Island) from 2014-2015. The outcome, PrEP utilization, was defined as patient PrEP use at three months. Multivariable logistic regression was performed to determine the association between insurance coverage and PrEP utilization. Of 201 patients (Jackson: 34%; St. Louis: 28%; Providence: 28%), 91% were male, 51% were White, median age was 29 years, and 21% were uninsured; 82% of patients reported taking PrEP at three months. Insurance coverage was significantly associated with PrEP utilization. After adjusting for Medicaid-expansion and individual socio-demographics, insured patients were four times as likely to use PrEP services compared to the uninsured (OR: 4.49, 95% CI: 1.68-12.01; p = 0.003). Disparities in insurance coverage are important considerations in implementation programs and may impede PrEP utilization.

Abstract  Full-text [free] access

Medication adherence, condom use and sexually transmitted infections in Australian PrEP users: interim results from the Victorian PrEP demonstration project

Lal L, Audsley J, Murphy D, Fairley CK, Stoove M, Roth N, Moore R, Tee BK, Puratmaja N, Anderson PL, Leslie D, Grant RM, De Wit J, Wright E; VicPrEP Study Team. AIDS. 2017 May 1 doi: 10.1097/QAD.0000000000001519. [Epub ahead of print]

Objective: HIV Pre-exposure prophylaxis (PrEP) decreases risk of HIV acquisition however its efficacy is closely dependent on adherence. There is also concern that the preventive effect of PrEP may be offset by risk compensation, notably an increase in condomless anal sex.

Design: Multi-site, open-label demonstration study that recruited people at current or recent risk of HIV infection in Melbourne, Australia.

Methods: Participants were recruited from three general practice clinics and one sexual health clinic in Melbourne and consented to take daily tenofovir/emtricitabine for 30 months. Sexual practice data, HIV and sexually transmitted infection (STI) test results were collected at baseline and 3-monthly during follow up. PrEP adherence was evaluated by self-report at clinical visits, online surveys, refill-based assessments and dried blood spot (DBS) testing. We present a 12-month interim analysis.

Results: 114 people were recruited. We observed a significant decline in condom use which occurred concomitantly with a significant increase in STIs over the first 12 months of PrEP. Incidence (per 100PY) of any STI was 43.2 and 119.8 at m0-3 and M3-12, respectively (IRR 2.77 (1.52, 5.56)). Adherence to PrEP medication was high by all measures, including six month TDF-FTC levels in DBS.

Conclusions: We found significant reduction in condom use and an increase STIs over the first 12 months of follow-up. High medication adherence rates coupled with a decline in condom use and a rise in STIs, suggests that prevention, early detection and treatment of STIs is a chief research priority in the current era of HIV PrEP.

Abstract

Men who have sex with men starting pre-exposure prophylaxis (PrEP) are at risk of HCV infection: evidence from the Amsterdam PrEP study

Hoornenborg E, Achterbergh RC, Van Der Loeff MF, Davidovich U, Hogewoning A, de Vries HJ, Schinkel J, Prins M, Laar TJWV; Amsterdam PrEP Project team in the HIV Transmission Elimination AMsterdam Initiative, MOSAIC study group. AIDS. 2017 May 1. doi: 10.1097/QAD.0000000000001522. [Epub ahead of print].

Objectives and Design: Hepatitis C virus (HCV) has been recognised as an emerging sexually transmitted infection (STI) among HIV-positive men who have sex with men (MSM). However, HIV-negative MSM at high risk for HIV might also be at increased risk for HCV. We studied the HCV prevalence in HIV-negative MSM who start pre-exposure prophylaxis (PrEP) in Amsterdam. Phylogenetic analysis was used to compare HCV strains obtained from HIV-negative and HIV-positive MSM.

Methods: At enrolment in the Amsterdam PrEP (AMPrEP) demonstration project, HIV-negative MSM were tested for the presence of HCV antibodies and HCV RNA. If positive for HCV RNA, an HCV NS5B gene fragment (709 bp) was sequenced and compared with HCV isolates from HIV-positive MSM (n = 223) and risk groups other than MSM (n = 153), using phylogenetic analysis.

Results: Of 375 HIV-negative MSM enrolled in AMPrEP, 18 (4.8%, 95%CI 2.9%-7.5%) of participants were anti-HCV and/or HCV RNA positive at enrolment; 15/18 (83%) had detectable HCV RNA. HCV genotyping showed genotype 1a (73%), 4d (20%) and 2b (7%). All HCV-positive MSM starting PrEP were part of MSM-specific HCV clusters containing MSM with and without HIV.

Conclusion: HCV prevalence among HIV-negative MSM who started PrEP was higher than previously reported. All HIV-negative HCV-positive MSM were infected with HCV strains already circulating among HIV-positive MSM. The increasing overlap between sexual networks of HIV-positive and HIV-negative MSM might result in an expanding HCV-epidemic irrespective of HIV-status. Hence, routine HCV testing should be offered to MSM at high risk for HIV, especially for those enrolling in PrEP programs.

Abstract

Safety and tolerability of long-acting cabotegravir injections in HIV-uninfected men (ECLAIR): a multicentre, double-blind, randomised, placebo-controlled, phase 2a trial.

Markowitz M, Frank I, Grant RM, Mayer KH, Elion R, Goldstein D, Fisher C, Sobieszczyk ME, Gallant JE, Van Tieu H, Weinberg W, . Margolis DA, Hudson KJ, Stancil BS, Ford SL, Patel P, Gould E, Rinehart AR, Smith KY, Spreen WR. Lancet HIV. 2017 May 22. pii: S2352-3018(17)30068-1. doi: 10.1016/S2352-3018(17)30068-1. [Epub ahead of print]

Background: Cabotegravir (GSK1265744) is an HIV-1 integrase strand transfer inhibitor with potent antiviral activity and a long half-life when administered by injection that prevented simian-HIV infection upon repeat intrarectal challenge in male macaques. We aimed to assess the safety, tolerability, and pharmacokinetics of long-acting cabotegravir injections in healthy men not at high risk of HIV-1 infection.

Methods: We did this multicentre, double-blind, randomised, placebo-controlled, phase 2a trial at ten sites in the USA. Healthy men (aged 18-65 years) deemed not at high risk of acquiring HIV-1 at screening were randomly assigned (5:1), via computer-generated central randomisation schedules, to receive cabotegravir or placebo. Participants received oral cabotegravir 30 mg tablets or matching placebo once daily during a 4 week oral lead-in phase, followed by a 1 week washout period and, after safety assessment, three intramuscular injections of long-acting cabotegravir 800 mg or saline placebo at 12 week intervals. Study site staff and participants were masked to treatment assignment from enrolment through week 41 (time of the last injection). The primary endpoint was safety and tolerability from the first injection (week 5) to 12 weeks after the last injection. We did analysis in the safety population, defined as all individuals enrolled in the study who received at least one dose of the study drug. This study is registered with ClinicalTrials.gov identifier, NCT02076178.

Findings: Between March 27, 2014, and Feb 23, 2016, we randomly assigned 127 participants to receive cabotegravir (n=106) or placebo (n=21); 126 (99%) participants comprised the safety population. Most participants were men who have sex with men (MSM; n=106 [83%]) and white (n=71 [56%]). 87 (82%) participants in the cabotegravir group and 20 (95%) participants in the placebo group completed the injection phase. Adverse events (n=7 [7%]) and injection intolerability (n=4 [4%]) were the main reasons for withdrawal in the cabotegravir group. The frequency of grade 2 or higher adverse events was higher in participants in the long-acting cabotegravir group (n=75 [80%]) than in those in the placebo group (n=10 [48%]; p=0·0049), mostly due to injection-site pain (n=55 [59%]). No significant differences were noted in concomitant medications, laboratory abnormalities, electrocardiogram, and vital sign assessments. Geometric mean trough plasma concentrations were 0·302 μg/mL (95% CI 0·237-0·385), 0·331 μg/mL (0·253-0·435), and 0·387 μg/mL (0·296-0·505) for injections one, two, and three, respectively, indicating lower than predicted exposure. The geometric mean apparent terminal phase half-life estimated after the third injection was 40 days. Two (2%) MSM acquired HIV-1 infection, one in the placebo group during the injection phase and one in the cabotegravir group 24 weeks after the final injection when cabotegravir exposure was well below the protein-binding-adjusted 90% inhibitory concentration.

Interpretation: Despite high incidence of transient, mild-to-moderate injection-site reactions, long-acting cabotegravir was well tolerated with an acceptable safety profile. Pharmacokinetic data suggest that 800 mg administered every 12 weeks is a suboptimal regimen; alternative dosing strategies are being investigated. Our findings support further investigation of long-acting injectable cabotegravir as an alternative to orally administered pre-exposure prophylaxis regimens.

Abstract

Examination of HIV infection through heterosexual contact with partners who are known to be HIV infected in the United States, 2010-2015

Crepaz N, Dong B, Chen M, Hall I. AIDS. 2017 Jul 17;31(11):1641-1644. doi: 10.1097/QAD.0000000000001526.

Using data from the National HIV Surveillance System, we examined HIV infections diagnosed between 2010 and 2015 attributed to heterosexual contact with partners previously known to be HIV infected. More than four in 10 HIV infections among heterosexual males and five in 10 HIV infections among heterosexual women were attributed to this group. Findings may inform the prioritization of prevention and care efforts and resource allocation modeling for reducing new HIV infection among discordant partnerships.

Abstract

A national study of the molecular epidemiology of HIV-1 in Australia 2005–2012

Castley A, Sawleshwarkar S, Varma R, Herring B, Thapa K, Dwyer D, Chibo D, Nguyen N, Hawke K, Ratcliff R, Garsia R, Kelleher A, Nolan D; Australian Molecular Epidemiology Network-HIV (AMEN-HIV).. PLoS One. 2017 May 10;12(5):e0170601. doi: 10.1371/journal.pone.0170601. eCollection 2017.

Introduction: Rates of new HIV-1 diagnoses are increasing in Australia, with evidence of an increasing proportion of non-B HIV-1 subtypes reflecting a growing impact of migration and travel. The present study aims to define HIV-1 subtype diversity patterns and investigate possible HIV-1 transmission networks within Australia.

Methods: The Australian Molecular Epidemiology Network (AMEN) HIV collaborating sites in Western Australia, South Australia, Victoria, Queensland and western Sydney (New South Wales), provided baseline HIV-1 partial pol sequence, age and gender information for 4873 patients who had genotypes performed during 2005-2012. HIV-1 phylogenetic analyses utilised MEGA V6, with a stringent classification of transmission pairs or clusters (bootstrap ≥98%, genetic distance ≤1.5% from at least one other sequence in the cluster).

Results: HIV-1 subtype B represented 74.5% of the 4873 sequences (WA 59%, SA 68.4%, w-Syd 73.8%, Vic 75.6%, Qld 82.1%), with similar proportion of transmission pairs and clusters found in the B and non-B cohorts (23% vs 24.5% of sequences, p = 0.3). Significantly more subtype B clusters were comprised of ≥3 sequences compared with non-B clusters (45.0% vs 24.0%, p = 0.021) and significantly more subtype B pairs and clusters were male-only (88% compared to 53% CRF01_AE and 17% subtype C clusters). Factors associated with being in a cluster of any size included; being sequenced in a more recent time period (p<0.001), being younger (p<0.001), being male (p = 0.023) and having a B subtype (p = 0.02). Being in a larger cluster (>3) was associated with being sequenced in a more recent time period (p = 0.05) and being male (p = 0.008).

Conclusion: This nationwide HIV-1 study of 4873 patient sequences highlights the increased diversity of HIV-1 subtypes within the Australian epidemic, as well as differences in transmission networks associated with these HIV-1 subtypes. These findings provide epidemiological insights not readily available using standard surveillance methods and can inform the development of effective public health strategies in the current paradigm of HIV prevention in Australia

Abstract  Full-text [free] access

HIV-1 full-genome phylogenetics of generalized epidemics in sub-Saharan Africa: impact of missing nucleotide characters in next-generation sequences.

Ratmann O, Wymant C, Colijn C, Danaviah S, Essex M, Frost SD, Gall A, Gaiseitsiwe S, Grabowski M, Gray R, Guindon S, von Haeseler A, Kaleebu P, Kendall M, Kozlov A, Manasa J, Minh BQ, Moyo S, Novitsky V, Nsubuga R, Pillay S, Quinn TC, Serwadda D, Ssemwanga D, Stamatakis A, Trifinopoulos J, Wawer M, Leigh Brown A, de Oliveira T, Kellam P, Pillay D, Fraser C.. AIDS Res Hum Retroviruses. 2017 May 25. doi: 10.1089/AID.2017.0061. [Epub ahead of print].

To characterize HIV-1 transmission dynamics in regions where the burden of HIV-1 is greatest, the 'Phylogenetics and Networks for Generalised HIV Epidemics in Africa' consortium (PANGEA-HIV) is sequencing full-genome viral isolates from across sub-Saharan Africa. We report the first 3985 PANGEA-HIV consensus sequences from four cohort sites (Rakai Community Cohort Study, n=2833; MRC/UVRI Uganda, n=701; Mochudi Prevention Project, n=359; Africa Health Research Institute Resistance Cohort, n=92). Next-generation sequencing success rates varied: more than 80% of the viral genome from the gag to the nef genes could be determined for all sequences from South Africa, 75% of sequences from Mochudi, 60% of sequences from MRC/UVRI Uganda, and 22% of sequences from Rakai. Partial sequencing failure was primarily associated with low viral load, increased for amplicons closer to the 3' end of the genome, was not associated with subtype diversity except HIV-1 subtype D, and remained significantly associated with sampling location after controlling for other factors. We assessed the impact of the missing data patterns in PANGEA-HIV sequences on phylogeny reconstruction in simulations. We found a threshold in terms of taxon sampling below which the patchy distribution of missing characters in next-generation sequences has an excess negative impact on the accuracy of HIV-1 phylogeny reconstruction, which is attributable to tree reconstruction artifacts that accumulate when branches in viral trees are long. The large number of PANGEA-HIV sequences provides unprecedented opportunities for evaluating HIV-1 transmission dynamics across sub-Saharan Africa and identifying prevention opportunities. Molecular epidemiological analyses of these data must proceed cautiously because sequence sampling remains below the identified threshold and a considerable negative impact of missing characters on phylogeny reconstruction is expected.

Abstract  Full-text [free] access

 

Africa, Asia, Europe, Northern America, Oceania
Afghanistan, Angola, Australia, Azerbaijan, Bangladesh, Benin, Bolivia, Botswana, Brazil, Burkina Faso, Burundi, Cambodia, Cameroon, Central African Republic, Chad, China, Comoros, Congo, Côte d'Ivoire, Democratic People's Republic of Korea, Democratic Republic of the Congo, Djibouti, Egypt, Equatorial Guinea, Eritrea, Ethiopia, Gabon, Gambia, Ghana, Guatemala, Guinea, Guinea-Bissau, Haiti, India, Indonesia, Iran (Islamic Republic of), Iraq, Jamaica, Kenya, Kyrgyzstan, Lao People's Democratic Republic, Lesotho, Liberia, Madagascar, Malawi, Mauritania, Mexico, Morocco, Mozambique, Myanmar, Namibia, Nepal, Netherlands, Niger, Nigeria, Pakistan, Papua New Guinea, Peru, Philippines, Russian Federation, Rwanda, Sao Tome and Principe, Senegal, Sierra Leone, Solomon Islands, Somalia, South Africa, South Sudan, Sudan, Swaziland, Tajikistan, Togo, Turkmenistan, Uganda, Ukraine, United Republic of Tanzania, United States of America, Uzbekistan, Viet Nam, Yemen, Zambia, Zimbabwe
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Phylogenetics - powerful new tools tied to ethical imperatives for key populations

Editor’s notes: There are now well over half a million HIV isolates that have been sequenced and the data stored in public accessible Genbank.  A systematic review by Hassan AS and colleagues of the methods used to define phylogenetic trees and clusters within them demonstrates the importance of using the correct criteria for the hypothesis being tested. Most articles use the pol sequence, since this is what is sequenced for drug resistance testing.  Most analyses have been done using a phylogenetic approach that uses a probability to assess the likelihood that isolates are clustered, and so depends on the cut-off value chosen.  For example, a well-studied outbreak of HIV among drug users in Finland is clearly linked to an earlier outbreak in Sweden, but because the Finnish isolates were collected later, they had already diverged somewhat from the Swedish ones.  If the threshold was set too high, they would not be recognized to be part of the same outbreak.  However for active transmission chains, a high threshold is needed to avoid falsely linking isolates.  There is no consensus on what methods to use, so caution is needed when comparing different studies.

Mark Wainberg, Professor of Medicine and of Microbiology at McGill University and a giant of Canadian HIV science, passed away this month.  So, as a tribute to his work, we have chosen a study from the McGill AIDS Centre by Brenner BG and colleagues.  The team used phylogenetic analysis to classify pre-treatment HIV isolates from 3901 men who have sex with men in Quebec according to the likelihood of being an acute or recent infection and the likelihood of clustering with other isolates.  Over the period from 2002-2015, a larger and larger proportion of the infections in this population could be linked to larger clusters, particularly involving younger men and men with recent infection, many of whom did not know their HIV status.  At least 40% of the onward spread of the epidemic in Quebec can be ascribed to just thirty clusters, varying in size from 20–140 individuals.

Using phylogenetics to understand transmission patterns requires careful attention to ethics, confidentiality and stigmatization.  A study in South Korea by Ahn MY and colleagues aimed to define the risk factors for clustering within clusters among 143 people living with HIV in four cities.  In eight out of the nine clusters identified participants did not report the same risk factors. Clusters were small, eight pairs and one quartet.  In the two tightest clusters, where the isolates were indistinguishable on the sequences examined, one man stated that he had sex with women, but the paired isolate came from another man and in the other pair, both men chose not to disclose their risk factors.  With small studies where information can sometimes be inferred even when not disclosed, it is perhaps not surprising that more than half the participants chose not to report their risk factors.

Other phylogenetic studies this month have explored the evolution of HIV recombination and the spread of different clades in communities in North-Eastern Brazil [Delatorre E et al.] and China.  In the North-Eastern states of Brazil, 72% of HIV isolates were subtype B, but rare subtypes such as D (1%) and CRF02_AG (1%) appear to be spreading within the population rather than being introduced from outside. In China studies from Sichuan [Wang Y et al.], Yunnan [Li Y and colleagues] and Zhejiang [Wang H et al.] have shown new recombinant forms of HIV with elements that suggest that viruses from different countries in the region have combined.  The widening diversity of HIV brings challenges for vaccine development, and potentially for HIV assays, such as those for recent infection that may differ in their sensitivity and specificity between different sub-types.  Understanding the migration of people and their viruses could be useful for providing better services, but careful attention to messaging will be needed to prevent such data from being used to discriminate further against migrants.

The final phylogenetic paper this month also comes from China, where Hao M and colleagues reported a study of students living with HIV in Beijing. The study demonstrated that transmitted drug resistance is still low in this setting, with just 0.8% of 237 students having virus that was resistant to non-nucleoside reverse transcriptase inhibitors that form part of the backbone of first line treatment in China.  A further 1.3% has resistance to protease inhibitors that are used in second line treatment.

Defining HIV-1 transmission clusters based on sequence data: a systematic review and perspectives.

Hassan AS, Pybus OG, Sanders EJ, Albert J, Esbjörnsson J. AIDS. 2017 Mar 28. doi: 10.1097/QAD.0000000000001470. [Epub ahead of print]

Understanding HIV-1 transmission dynamics is relevant to both screening and intervention strategies of HIV-1 infection. Commonly, HIV-1 transmission chains are determined based on sequence similarity assessed either directly from a sequence alignment or by inferring a phylogenetic tree. This review is aimed at both nonexperts interested in understanding and interpreting studies of HIV-1transmission, and experts interested in finding the most appropriate cluster definition for a specific dataset and research question. We start by introducing the concepts and methodologies of how HIV-1 transmission clusters usually have been defined. We then present the results of a systematic review of 105 HIV-1 molecular epidemiology studies summarizing the most popular methods and definitions in the literature. Finally, we offer our perspectives on how HIV-1 transmission clusters can be defined and provide some guidance based on examples from real life datasets.

Abstract access 

Large cluster outbreaks sustain the HIV epidemic among MSM in Quebec.

Brenner BG, Ibanescu RI, Hardy I, Stephens D, Otis J, Moodie E, Grossman Z,Vandamme AM, Roger M, Wainberg MA; and the Montreal PHI, SPOT cohorts. AIDS. 2017 Mar 13;31(5):707-717. doi: 10.1097/QAD.0000000000001383.

Objective: HIV-1 epidemics among MSM remain unchecked despite advances in treatment and prevention paradigms. This study combined viral phylogenetic and behavioural risk data to better understand underlying factors governing the temporal growth of the HIV epidemic among MSM in Quebec (2002-2015).

Methods: Phylogenetic analysis of pol sequences was used to deduce HIV-1transmission dynamics (cluster size, size distribution and growth rate) in first genotypes of treatment-naïve MSM (2002-2015, n = 3901). Low sequence diversity of first genotypes (0-0.44% mixed base calls) was used as an indication of early-stage infection. Behavioural risk data were obtained from the Montreal rapid testing site and primary HIV-1-infection cohorts.

Results: Phylogenetic analyses uncovered high proportion of clustering of new MSM infections. Overall, 27, 45, 48, 53 and 57% of first genotypes within one (singleton, n = 1359), 2-4 (n = 692), 5-9 (n = 367), 10-19 (n = 405) and 20+ (n = 1277) cluster size groups were early infections (<0.44% diversity). Thirty viruses within large 20+ clusters disproportionately fuelled the epidemic, representing 13, 25 and 42% of infections, first genotyped in 2004-2007 (n = 1314), 2008-2011 (n = 1356) and 2012-2015 (n = 1033), respectively. Of note, 35, 21 and 14% of MSM belonging to 20+, 2-19 and one (singleton) cluster groups were under 30 years of age, respectively. Half of persons seen at the rapid testing site (2009-2011, n = 1781) were untested in the prior year. Poor testing propensity was associated with fewer reported partnerships.

Conclusion: Addressing the heterogeneity in transmission dynamics among HIV-1-infected MSM populations may help guide testing, treatment and prevention strategies.

Abstract access 

HIV-1 transmission networks across South Korea.

Ahn MY, Wertheim JO, Kim WJ, Kim SW, Lee JS, Ann HW, Jeon Y, Ahn JY, Song JE, Oh DH, Kim YC, Kim EJ), Jung IY, Kim MH, Jeong W, Jeong SJ, Ku NS, Kim JM, Smith DM, Choi JY. AIDS Res Hum Retroviruses. 2017 Mar 27. doi: 10.1089/aid.2016.0212. [Epub ahead of print]

Molecular epidemiology can help clarify the properties and dynamics of HIV-1 transmission networks in both global and regional scales. We studied 143 HIV-1-infected individuals recruited from four medical centers of three cities in South Korea between April 2013 and May 2014. HIV-1 env V3 sequence data were generated (337-793 bp) and analyzed using a pairwise distance-based clustering approach to infer putative transmission networks. Participants whose viruses were ≤2.0% divergent according to Tamura-Nei 93 genetic distance were defined as clustering. We collected demographic, risk, and clinical data and analyzed these data in relation to clustering. Among 143 participants, we identified nine putative transmission clusters of different sizes (range 2-4 participants). The reported risk factor of participants were concordant in only one network involving two participants, that is, both individuals reported homosexual sex as their risk factor. The participants in the other eight networks did not report concordant risk factors, although they were phylogenetically linked. About half of the participants refused to report their risk factor. Overall, molecular epidemiology provides more information to understand local transmission networks and the risks associated with these networks.

Abstract access 

HIV-1 Genetic diversity in northeastern Brazil: high prevalence of non-B subtypes.

Delatorre E, Couto-Fernandez JC, Bello G.AIDS Res Hum Retroviruses. 2017 Mar 22. doi: 10.1089/AID.2017.0045. [Epub ahead of print]

The Northeastern Brazilian region has experienced a constant increase in the number of newly reported AIDS cases over the last decade, but the genetic diversity of HIV-1 strains currently disseminated in this region remains poorly explored. HIV-1 pol sequences were obtained from 140 patients followed at outpatient clinics from four Northeastern Brazilian states (Alagoas, Bahia, Ceará and Piauí) between 2014 and 2015. Subtype B was the most prevalent HIV-1 clade (72%) detected in the Northeastern region, followed by subtypes F1 (6%), C (5%) and D (1%). The remaining strains (16%) displayed a recombinant structure and were classified as: BF1 (11%), BC (4%), BCF1 (1%) and CRF02_AG-like (1%). The 20 HIV-1 BF1 and BC recombinant sequences detected were distributed among 11 lineages classified as: CRF28/29_BF-like (n = 5), CRF39_BF-like (n = 1), URFs_BF (n = 9) and URFs_BC (n = 5). Non-B subtypes were detected in all Northeastern Brazilian states, but with variable prevalence, ranging from 16% in Ceará to 55% in Alagoas. Phylogenetics analyses support that subtype D and CRF02_AG strains detected in the Northeastern region resulted from the expansion of autochthonous transmission networks, rather than from exogenous introductions from other countries. These results reveal that HIV-1 epidemic spreading in the Northeastern Brazilian region is comprised by multiple subtypes and recombinant strains and that the molecular epidemiologic pattern in this Brazilian region is much more complex than originally estimated.

Abstract access 

Identification of a novel HIV type 1 CRF01_AE/B'/C recombinant isolate in Sichuan, China.

Wang Y, Kong D, Xu W, Li F, Liang S, Feng Y, Zhang F, Shao Y, Ma L. AIDS Res Hum Retroviruses. 2017 Mar 13. doi: 10.1089/aid.2017.0002. [Epub ahead of print]

We report in this study a novel HIV-1 unique recombinant virus (XC2014EU01) isolated from an HIV-positive man who infected through heterosexual sex in Sichuan, China. The near full-length genome analyses showed that XC2014EU01 harbored one subtype B segment in pol region and two subtype C segments in gag-pol region in a CRF01_AE backbone. The unique mosaic structure was distinctly different from the other CRF01_AE/B'/C recombinant forms reported. Phylogenetic tree analyses revealed that the subtype B region originated from a Thailand subtype B' lineage, the subtype C regions were from an India C lineage, and the backbone was from CRF01_AE. XC2014EU01 was still identified as CCR5-tropic, and plasma of XC2014EU01 infected person had the media neutralizing activity. The emergence of XC2014EU01 may increase the complexity of the HIV-1 epidemic among high-risk populations and the difficulty of vaccine research and development.

Abstract access 

Identification of a novel HIV type 1 circulating recombinant form (CRF86_BC) among heterosexuals in Yunnan, China.

Li Y, Miao J, Miao Z, Song Y, Wen M, Zhang Y, Guo S, Zhao Y, Feng Y, Xia X. AIDS Res Hum Retroviruses. 2017 Mar;33(3):279-283. doi: 10.1089/AID.2016.0188. Epub 2016 Oct 18.

In recent years, multiple circulating recombinant forms (CRFs) and unique recombinant forms of human immunodeficiency virus type 1 (HIV-1) have been described in Yunnan, China. Here, we identified a novel HIV-1 CRF (CRF86_BC) isolated from three heterosexuals with no obvious epidemiologic linkage in western Yunnan (Baoshan prefecture) in China. CRF86_BC had a subtype C backbone with four subtype B fragments inserted into the pol, vpr, vpu, env, and nef gene regions, respectively. Furthermore, subregion tree analysis revealed that subtype C backbone originated from an Indian C lineage and subtype B segment inserted was from a Thai B lineage. They are different from previously documented B/C forms in its distinct backbone, inserted fragment size, and break points. This highlighted the importance of continual monitoring of genetic diversity and complexity of HIV-1 strains in this region.

Abstract access 

Near full-length genomic characterization of a novel HIV-1 unique recombinant (CRF55_01B/CRF07_BC) from a Malaysian immigrant worker in Zhejiang, China.

Wang H, Luo P, Zhu H, Wang N, Hu J, Mo Q, Yang Z, Feng Y. AIDS Res Hum Retroviruses. 2017 Mar;33(3):275-278.doi: 10.1089/AID.2016.0100. Epub 2016 Aug 17.

Recombinant forms contribute substantially to the genetic diversity of human immunodeficiency virus type 1 (HIV-1). Here we report a novel HIV-1 recombinant detected from a comprehensive HIV-1 molecular epidemiologic study among cross-border populations in China. Near full-length genome (NFLG) phylogenetic analysis showed that the novel HIV-1 recombinant ZJCIQ15005, which was isolated from a Malaysian immigrant worker in Zhejiang, China, clustered with CRF55_01B reference sequences but set up a distinct branch. Recombinant analysis showed that the NFLG of ZJCIQ15005 composed of CRF55_01B (as the backbone) and CRF07_BC,with 12 recombinant break points observed in the pol, vif, vpr, tat, rev, env,nef, and 3'LTR regions. This is the first detection of a novel HIV-1 recombinant (CRF55_01B/CRF07_BC) in immigrant workers in China. The emergence of this recombinant may increase the complexity of the HIV-1 epidemic in China and suggests the importance of continuous surveillance of the dynamic changes of HIV-1.

Abstract access 

Low rates of transmitted drug resistances among treatment-naive HIV-1 infected students in Beijing, China.

Hao M, Wang J, Xin R, Li X, Hao Y, Chen J, Ye J, Wang Y, He X, Huang C, Lu H. AIDS Res Hum Retroviruses. 2017 Mar 22. doi: 10.1089/AID.2017.0053. [Epub ahead of print]

Beijing has seen a rising epidemic of HIV among students. However, little information was known about the molecular epidemiologic data among HIV-infected students. In this study, the diversity and the prevalence of TDR in pol sequences deriving from 237 HIV-infected students were analyzed. TDR mutations were found in 5 MSM among students. The overall prevalence of TDR in students was 2.1%, comprised of 1.3% to protease inhibitors and 0.8 % to non-nucleoside reverse transcriptase inhibitors. Our finding indicates a low-level prevalence of TDR mutations among students in Beijing.

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Asia, Latin America, Northern America
Brazil, Canada, China, Republic of Korea
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Infectious co-morbidities – why are people still dying of advanced HIV infections?

Editor’s notes: Tuberculosis remains the biggest reported killer of people living with HIV.  Studies from Guangxi, China and Nigeria examine risk factors for tuberculosis.  In the Chinese study, Cui Z and colleagues found almost one in six of 1019 people receiving care for HIV had active tuberculosis.  The risk factors that they found when comparing these 160 people with tuberculosis to matched controls living with HIV but without tuberculosis were well-known (low CD4 cell count, smoking and non-use of ART).  Long duration of HIV infection was also independently associated with developing tuberculosis, emphasising the need for tuberculosis specific measures in addition to ART.  The authors recommend standard approaches that need to be strengthened (active screening and case-finding with early initiation of ART; isoniazid preventive therapy and better infection control).  The most extraordinary statistic is how much higher the rate of tuberculosis is among this group of people receiving HIV care than it is among the general population of Guangxi.  173 times higher is pretty impressive!

The Pathmanathan I et al. study in Nigeria, carried out as part of a broader analysis of the outcomes of a nationally representative sample of people taking ART, is more optimistic.  The incidence rate for tuberculosis once people started on ART was 0.57 per 100 person years, which compares quite favourably with the estimated incidence for Nigeria from the WHO Global Tuberculosis 2016 report [link] of 0.32 per 100 person years.  Furthermore, most of the incident tuberculosis occurred soon after starting ART and (as might be expected) was most common in people with low CD4 count; previous tuberculosis or suspected but not diagnosed tuberculosis on starting ART.  Once people’s CD4 count was above 200 cells per ml, the incidence rate was 0.29 per 100 person-years.  This is encouraging, as it suggests that a good ART programme could have a significant impact on the overall risk of tuberculosis.  The aim of collaborative tuberculosis and HIV programme efforts must be to find people living with HIV before they are so immunocompromised.  In this study, the average CD4 count at enrolment was less than 200 cells per ml and around 5% of people already had tuberculosis at that time.

Late HIV diagnosis was also the subject of a study from Jiangsu province in China.  Hu H and colleagues looked at the trends in HIV testing and presentation to care before the CD4 count fell below 350 cells per ml.  From 2011-2014 in cross-sectional annual community based surveys among around 2500 men who have sex with men (MSM), there was a modest decline in the proportion who had had an HIV test within the last 12 months from 60% to 53%, and late presentation remained stable around 40%.  We have to shift from this plateau and the authors point out that HIV self-tests seem highly acceptable to MSM in China and that social media and internet based advocacy might also help.

There is increasing interest in co-infections with hepatitis B and C viruses in people living with HIV.  Hepatitis B is widespread in many countries in sub-Saharan Africa with “horizontal” transmission occurring in childhood.  Vaccination is now included as part of some countries programmes on expanded immunisation.  Co-infection with HIV and Hepatitis B leads to more rapid progression of liver damage and to liver cancer. Seremba E and colleagues tested stored sera from people living with HIV in the Rakai community and found that around half had already been infected with hepatitis B (in line with the high prevalence of infection in children).  During the follow up samples from people who were hepatitis B negative, new infections with hepatitis B occurred in 39 individuals, giving an incidence rate of 1.2 per 100 person years.  While hepatitis B vaccine is recommended for people living with HIV who are not infected, this study shows that ART is also protective, particularly if it contains lamivudine or tenofovir.  So this may be an added benefit of the wider scale-up of ART.

Despite advance in ART, too many people still die with HIV-associated infections that are only seen at low CD4 cell counts.  An important example is cryptococcal meningitis, which causes an insidious onset of symptoms. By the time patients are seen at the hospital with severe headache and signs of raised intracranial pressure it is often too late to prevent them from dying. This is because the best medicines (liposomal amphotericin and flucytosine) are expensive and often not available.  So WHO recommends pre-emptive treatment for people who are first seen at the health service with CD4 counts less than 100 cells per ml and with cryptococcal antigen (CRAG) detectable in the blood.  A modelling study by Ramachandran A et al. from Uganda and the US considered the likely costs and benefits of using a new lateral flow assay for CRAG for people living with HIV with a low CD4 count, with pre-emptive treatment with fluconazole for people found to be CRAG-positive. The results, including various sensitivity tests, are strongly in favour of widespread implementation of this strategy. The authors calculate that it would cost Uganda around US$650 000 per year and would avert more than a thousand deaths.  Like the tuberculosis discussions above, the real aim is to prevent people living with HIV reaching the stage where “old-fashioned” opportunistic infections can cause such misery.  However in the medium term, we are likely to continue to see many people presenting late in the course of their infections, and CRAG (and tuberculosis) screening and management are key ways to prevent mortality.

Risk factors associated with Tuberculosis (TB) among people living with HIV/AIDS: A pair-matched case-control study in Guangxi, China.

Cui Z, Lin M, Nie S, Lan R. PLoS One. 2017 Mar 30;12(3):e0173976. doi:10.1371/journal.pone.0173976.eCollection 2017.

Background: As one of the poorest provinces in China, Guangxi has a high HIV and TB prevalence, with the annual number of TB/HIV cases reported by health department among the highest in the country. However, studies on the burden of TB-HIV co-infection and risk factors for active TB among HIV-infected persons in Guangxi have rarely been reported.

Objective: To investigate the risk factors for active TB among people living with HIV/AIDS in Guangxi Zhuang autonomous region, China.

Methods: A surveillance survey was conducted of 1019 HIV-infected patients receiving care at three AIDS prevention and control departments between 2013 and 2015. We investigated the cumulative prevalence of TB during 2 years. To analyze risk factors associated with active TB, we conducted a 1:1 pair-matched case-control study of newly reported active TB/HIV co-infected patients. Controls were patients with HIV without active TB, latent TB infection or other lung disease, who were matched with the case group based on sex and age (± 3 years).

Results: A total of 1019 subjects were evaluated. 160 subjects (15.70%) were diagnosed with active TB, including 85 clinically diagnosed cases and 75 confirmed cases. We performed a 1:1 matched case-control study, with 82 TB/HIV patients and 82 people living with HIV/AIDS based on surveillance site, sex and age (±3) years. According to multivariate analysis, smoking (OR = 2.996, 0.992-9.053), lower CD4+ T-cell count (OR = 3.288, 1.161-9.311), long duration of HIV-infection (OR = 5.946, 2.221-15.915) and non-use of ART (OR = 7.775, 2.618-23.094) were independent risk factors for TB in people living with HIV/AIDS.

Conclusion: The prevalence of active TB among people living with HIV/AIDS in Guangxi was 173 times higher than general population in Guangxi. It is necessary for government to integrate control planning and resources for the two diseases. Medical and public health workers should strengthen health education for TB/HIV prevention and treatment and promote smoking cessation. Active TB case finding and early initiation of ART is necessary to minimize the burden of disease among patients with HIV, as is IPT and infection control in healthcare facilities.

Abstract  Full-text [free] access

Incidence and predictors of tuberculosis among HIV-infected adults after initiation of antiretroviral therapy in Nigeria, 2004-2012.

Pathmanathan I, Dokubo EK, Shiraishi RW, Agolory SG, Auld AF, Onotu D, Odafe S, Dalhatu I, Abiri O, Debem HC, Bashorun A, Ellerbrock T. PLoS One. 2017 Mar 10;12(3):e0173309. doi: 10.1371/journal.pone.0173309.eCollection 2017.

Background: Nigeria had the most AIDS-related deaths worldwide in 2014 (170 000), and 46% were associated with tuberculosis (TB). Although treatment of people living with HIV (PLHIV) with antiretroviral therapy (ART) reduces TB-associated morbidity and mortality, incident TB can occur while on ART. We estimated incidence and characterized factors associated with TB after ART initiation in Nigeria.

Methods: We analyzed retrospective cohort data from a nationally representative sample of adult patients on ART. Data were abstracted from 3496 patient records, and analyses were weighted and controlled for a complex survey design. We performed domain analyses on patients without documented TB disease and used a Cox proportional hazard model to assess factors associated with TB incidence after ART.

Results: At ART initiation, 3350 patients (95.8%) were not receiving TB treatment. TB incidence after ART initiation was 0.57 per 100 person-years, and significantly higher for patients with CD4<50/μL (adjusted hazard ratio [AHR]:4.2, 95% confidence interval [CI]: 1.4-12.7) compared with CD4≥200/μL. Patients with suspected but untreated TB at ART initiation and those with a history of prior TB were more likely to develop incident TB (AHR: 12.2, 95% CI: 4.5-33.5 and AHR: 17.6, 95% CI: 3.5-87.9, respectively).

Conclusion: Incidence of TB among PLHIV after ART initiation was low, and predicted by advanced HIV, prior TB, and suspected but untreated TB. Study results suggest a need for improved TB screening and diagnosis, particularly among high-risk PLHIV initiating ART, and reinforce the benefit of early ART and other TB prevention efforts.

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Trends in late HIV diagnosis among men who have sex with men in Jiangsu province, China: Results from four consecutive community-based surveys, 2011-2014.

Hu H, Yan H, Liu X, Xu X, Xu J, Qiu T, Shi LE, Fu G, HuanX, McFarland W, Wei C). PLoS One. 2017 Mar 9;12(3):e0172664. doi:10.1371/journal.pone.0172664.eCollection 2017.

Objectives: To examine trends in HIV testing, late HIV diagnosis and associated factors among men who have sex with men (MSM) in Jiangsu province, China.

Methods: Four consecutive community-based cross-sectional surveys were conducted among MSM from 2011 to 2014 in eight cities in the province. Participants were recruited from MSM venues and via the internet. HIV bio-behavioral surveys were conducted to collect demographic and behavioral data and measure HIV infection. HIV-infected participants with CD4 counts less than 350 cells/µL were defined as having a late HIV diagnosis. Chi-square trend tests were used to compare temporal changes over the years and multivariable logistic regression analyses were used to identify factors associated with late diagnosis.

Results: A total of 2441, 2677, 2591 and 2610 participants were enrolled in 2011, 2012, 2013 and 2014, respectively. Testing for HIV in the last 12 months decreased over the time period, from 59.9% to 52.5% (p<0.001). Late HIV diagnosis remained high and steady, ranging from 33.3% to 44.2% over the years with no significant change over time (p = 0.418). MSM who were older than 24 years (aOR =1.748, p = 0.020 for 25-39 years old; aOR = 3.148, p<0.001 for 40 years old or older), were recruited via internet (aOR = 1.596, p = 0.024), and did not have an HIV test in the past 12 months (aOR = 3.385, p<0.001) were more likely to be late diagnosed.

Conclusions: Our study showed a plateau in HIV testing among MSM in China, in parallel to high levels of late diagnosis. Emerging and innovative strategies such as HIV self-testing and reaching more MSM by internet, both highly acceptable to MSM in China, may reduce late diagnosis.

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Hepatitis B incidence and prevention with antiretroviral therapy among HIV-positive individuals in Uganda.

Seremba E, Ssempijja V, Kalibbala S, Gray RH, Wawer MJ, Nalugoda F, Casper C, Phipps W, Ocama P, Serwadda D, Thomas DL, Reynolds SJ. 123. AIDS. 2017 Mar 27;31(6):781-786. doi: 10.1097/QAD.0000000000001399.

Objective: Antiretroviral therapy (ART) may interfere with replication of hepatitis B virus (HBV), raising the hypothesis that HBV infection might be prevented by ART. We investigated the incidence and risk factors associated with HBV among HIV-infected adults in Rakai, Uganda.

Methods: We screened stored sera from 944 HIV-infected adults enrolled in the Rakai Community Cohort Study between September 2003 and March 2015 for evidence of HBV exposure. Serum from participants who tested anti-hepatitis B core-negative (497) at baseline were tested over 3-7 consecutive survey rounds for incident HBV. Poisson incidence methods were used to estimate incidence of HBV with 95% confidence intervals (CIs), whereas Cox proportional regression methods were used to estimate hazard ratios (HRs).

Results: Thirty-nine HBV infections occurred over 3342 person-years, incidence1.17/100 person-years. HBV incidence was significantly lower with ART use: 0.49/100 person-years with ART and 2.3/100 person-years without ART [adjusted HR (aHR) 0.25, 95% CI 0.1-0.5, P < 0.001], and with lamivudine (3TC) use: (0.58/100 person-years) with 3TC and 2.25/100 person-years without 3TC (aHR 0.32, 95% CI0.1-0.7, P =  < 0.007). No new HBV infections occurred among those on tenofovir-based ART. HBV incidence also decreased with HIV RNA suppression: 0.6/100 person-years with 400 copies/ml or less and 4.0/100 person-years with more than 400 copies/ml (aHR, 6.4, 95% CI 2.2-19.0, P < 0.001); and with age: 15-29 years versus 40-50 years (aHR 3.2, 95% CI 1.2-9.0); 30-39 years versus 40-50 years (aHR 2.1, 95% CI 0.9-5.3).

Conclusion: HBV continues to be acquired in adulthood among HIV-positive Ugandans and HBV incidence is dramatically reduced with HBV-active ART. In addition to widespread vaccination, initiation of ART may prevent HBV acquisition among HIV-positive adults in sub-Saharan Africa.

Abstract access 

Cost-effectiveness of CRAG-LFA screening for cryptococcal meningitis among people living with HIV in Uganda.

Ramachandran A(1), Manabe Y(1,)(2), Rajasingham R(3), Shah M(4).141. BMC Infect Dis. 2017 Mar 23;17(1):225. doi: 10.1186/s12879-017-2325-9.

Background: Cryptococcal meningitis (CM) constitutes a significant source of mortality in resource-limited regions. Cryptococcal antigen (CRAG) can be detected in the blood before onset of meningitis. We sought to determine the cost-effectiveness of implementing CRAG screening using the recently developed CRAG lateral flow assay in Uganda compared to current practice without screening.

Methods: A decision-analytic model was constructed to compare two strategies for cryptococcal prevention among people living with HIV with CD4 < 100 in Uganda: No cryptococcal screening vs. CRAG screening with WHO-recommended preemptive treatment for CRAG-positive patients. The model was constructed to reflect primary HIV clinics in Uganda, with a cohort of HIV-infected patients withCD4 < 100 cells/µL. Primary outcomes were expected costs, DALYs, and incremental cost-effectiveness ratios (ICERs). We evaluated varying levels of programmatic implementation in secondary analysis.

Results: CRAG screening was considered highly cost-effective and was associated with an ICER of $6.14 per DALY averted compared to no screening (95% uncertainty range: $-20.32 to $36.47). Overall, implementation of CRAG screening was projected to cost $1.52 more per person, and was projected to result in a 40% relative reduction in cryptococcal-associated mortality. In probabilistic sensitivity analysis, CRAG screening was cost-effective in 100% of scenarios and cost saving (ie cheaper and more effective than no screening) in 30% of scenarios. Secondary analysis projected a total cost of $651 454 for 100%implementation of screening nationally, while averting 1228 deaths compared to no screening.

Conclusion: CRAG screening for PLWH with low CD4 represents excellent value for money with the potential to prevent cryptococcal morbidity and mortality in Uganda.

Abstract  Full-text [free] access

Africa, Asia
China, Nigeria, Uganda
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Peer support: not a panacea for poor adherence

Use of peers to improve adherence to antiretroviral therapy: a global network meta-analysis.

Kanters S, Park JJ, Chan K, Ford N, Forrest J, Thorlund K, Nachega JB, Mills EJ. J Int AIDS Soc. 2016 Nov 30;19(1):21141. doi: 10.7448/IAS.19.1.21141. eCollection 2016.

Introduction: It is unclear whether using peers can improve adherence to antiretroviral therapy (ART). To construct the World Health Organization's global guidance on adherence interventions, we conducted a systematic review and network meta-analysis to determine the effectiveness of using peers for achieving adequate adherence and viral suppression.

Methods: We searched for randomized clinical trials of peer-based interventions to promote adherence to ART in HIV populations. We searched six electronic databases from inception to July 2015 and major conference abstracts within the last three years. We examined the outcomes of adherence and viral suppression among trials done worldwide and those specific to low- and middle-income countries (LMIC) using pairwise and network meta-analyses.

Results and discussion: Twenty-two trials met the inclusion criteria. We found similar results between pairwise and network meta-analyses, and between the global and LMIC settings. Peer supporter+Telephone was superior in improving adherence than standard-of-care in both the global network (odds-ratio [OR]=4.79, 95% credible intervals [CrI]: 1.02, 23.57) and the LMIC settings (OR=4.83, 95% CrI: 1.88, 13.55). Peer support alone, however, did not lead to improvement in ART adherence in both settings. For viral suppression, we found no difference of effects among interventions due to limited trials.

Conclusions: Our analysis showed that peer support leads to modest improvement in adherence. These modest effects may be due to the fact that in many settings, particularly in LMICs, programmes already include peer supporters, adherence clubs and family disclosures for treatment support. Rather than introducing new interventions, a focus on improving the quality in the delivery of existing services may be a more practical and effective way to improve adherence to ART.

Abstract  Full-text [free] access 

Editor’s notes: Sustained adherence to antiretroviral therapy (ART) is critical to ensure successful treatment outcomes and prevent drug resistance, AIDS-associated illness, death and onward transmission of HIV infection. In recent years, there has been much enthusiasm for use of peer support as a programme to improve adherence. Most high HIV prevalence settings have limited resources. Stigma influences adherence to treatment, and peer-based support may be a practical solution both in terms of being low cost and a mechanism for addressing stigma.

In this systematic review, the authors evaluated the effectiveness of peer-supporter programmes alone or in combination with other activities, namely telephone calls, device reminders or cognitive behavioural therapy (CBT), globally and in low and middle-income countries (LMIC). The systematic review findings were used to inform the 2015 World Health Organization HIV treatment guidelines.

The study demonstrates that peer support alone did not have any impact on adherence or on viral suppression. It did demonstrate modest improvements on adherence when combined with telephone activities. Several factors need to be considered in interpreting these findings. Firstly, adherence was assessed using a variety of methods including pill counts and the Medication Event Monitoring System (MEMS), which may have introduced heterogeneity. Secondly, few trials (particularly in LMICs) used HIV viral load as an outcome and therefore there may not have been adequate statistical power to detect an effect. Thirdly, populations included in the review were heterogeneous e.g. ART-naïve and experienced, people who inject drugs, non-adherent individuals. Notably, only one trial included children and adolescents among whom adherence is typically poorer. 

Importantly, in many settings particularly in LMICs, programmes already include treatment supporters and adherence clubs and therefore additional peer support would likely not add additional impact. The findings of this study suggest that programmes should focus on improving the quality of existing services rather than introduce new programmes. The review also highlights the need to standardise adherence measures and the need for robust research on adherence, particularly among children.         

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High prevalence of gender based violence among adolescent female sex workers - need to improve access to health services

Prevalence and correlates of sexual and gender-based violence against Chinese adolescent women who are involved in commercial sex: a cross-sectional study.

Zhang XD, Myers S, Yang HJ, Li Y, Li JH, Luo W, Luchters S. BMJ Open. 2016 Dec 19;6(12):e013409. doi: 10.1136/bmjopen-2016-013409.

Objectives: Despite the vast quantity of research among Chinese female sex workers (FSWs) to address concerns regarding HIV/sexually transmitted infection (STI) risk, there is a paucity of research on issues of sexual and gender-based violence (SGBV) and the missed opportunity for sexual and reproductive health (SRH) promotion among young FSWs. Our research aimed to assess the prevalence and correlates of SGBV among Chinese adolescent FSWs, and to explore SRH service utilisation.

Design and methods: A cross-sectional study using a one-stage cluster sampling method was employed. A semistructured questionnaire was administered by trained peer educators or health workers. Multivariable logistic regression was conducted to determine individual and structural correlates of SGBV.

Setting and participants: Between July and September 2012, 310 adolescent women aged 15-20 years, and who self-reported having received money or gifts in exchange for sex in the past 6 months were recruited and completed their interview in Kunming, Yunnan Province, China.

Results: Findings confirm the high prevalence of SGBV against adolescent FSWs in China, with 38% (118/310) of participants affected in the past year. Moreover, our study demonstrated the low uptake of public health services and high rates of prior unwanted pregnancy (52%; 61/118), abortion (53%; 63/118) and self-reported STI symptoms (84%; 99/118) in participants who were exposed to SGBV. Forced sexual debut was reported by nearly a quarter of FSWs (23%; 70/310) and was independently associated with having had a drug-using intimate partner and younger age (<17 years old) at first abortion. When controlling for potential confounders, having experienced SGBV was associated with frequent alcohol use, having self-reported symptoms of STI, having an intimate partner and having an intimate partner with illicit drug use.

Conclusions: This study calls for effective and integrated interventions addressing adolescent FSWs' vulnerability to SGBV and broader SRH consequences.

Abstract  Full-text [free] access 

Editor’s notes: The paper reports a study conducted to measure the prevalence and correlates of sexual and gender-based violence among Chinese adolescent female sex workers, given the paucity of data on this. A cross-sectional survey was conducted in the Yunnan Province, which has a relatively high HIV-1 prevalence. Around 300 women aged 15-19 years, who had received money or gifts in exchange for sex in the past six months were recruited for a survey.

The survey revealed that over half the female sex workers were married or cohabiting but lived predominantly with other sex workers or friends, or alone. The majority reported that they had been a sex worker for less than six months. Over the past year, 82% of the female sex workers had an intimate partner, and most of these relationships were for less than one year. Alcohol use was common, with 83% of the female sex workers reporting drinking alcohol at least twice a week. Inconsistent condom use in the past month was reported by 57% of the female sex workers.

Around a quarter of women’s first sexual experience was forced. Thirty-eight per cent of the female sex workers reported having experienced sexual and gender-based violence in the past year, with three quarters of women reporting the perpetrator as their intimate male partner and (62%) a male paying client. The female sex workers experiencing sexual and gender-based violence in the past year were more likely to be frequent drinkers or have a drug-using intimate partner. Women who experienced sexual and gender-based violence were more likely to report unwanted pregnancy, and less likely to use public health facilities or HIV testing services.

The authors suggest that their findings reveal a missed opportunity for the public health sector to address sexual and gender-based violence and associated sexual and reproductive health issues. However, they suggested there is a need to involve women-led community-based organisations to build relationships with female sex workers to enable them to utilise such services. There is also a need for further research on integrated programmes to prevent or reduce sexual and gender-based violence against adolescent female sex workers. 

Epidemiology, Gender
Asia
China
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Improving ART adherence: what works?

Interventions to improve adherence to antiretroviral therapy: a systematic review and network meta-analysis.

Kanters S, Park JJ, Chan K, Socias ME, Ford N, Forrest JI, Thorlund K, Nachega JB, Mills EJ. Lancet HIV. 2017 Jan;4(1):e31-e40. doi: 10.1016/S2352-3018(16)30206-5. Epub 2016 Nov 16.

Background: High adherence to antiretroviral therapy is crucial to the success of HIV treatment. We evaluated comparative effectiveness of adherence interventions with the aim of informing the WHO's global guidance on interventions to increase adherence.

Methods: For this systematic review and network meta-analysis, we searched for randomised controlled trials of interventions that aimed to improve adherence to antiretroviral therapy regimens in populations with HIV. We searched Cochrane Central Register of Controlled Trials, Embase, and MEDLINE for reports published up to July 16, 2015, and searched major conference abstracts from Jan 1, 2013, to July 16, 2015. We extracted data from eligible studies for study characteristics, interventions, patients' characteristics at baseline, and outcomes for the study populations of interest. We used network meta-analyses to compare adherence and viral suppression for all study settings (global network) and for studies in low-income and middle-income countries only (LMIC network).

Findings: We obtained data from 85 trials with 16 271 participants. Short message service (SMS; text message) interventions were superior to standard of care in improving adherence in both the global network (odds ratio [OR] 1.48, 95% credible interval [CrI] 1.00-2.16) and in the LMIC network (1.49, 1.04-2.09). Multiple interventions showed generally superior adherence to single interventions, indicating additive effects. For viral suppression, only cognitive behavioural therapy (1.46, 1.05-2.12) and supporter interventions (1.28, 1.01-1.71) were superior to standard of care in the global network; none of the interventions improved viral response in the LMIC network. For the global network, the time discrepancy (whether the study outcome was measured during or after intervention was withdrawn) was an effect modifier for both adherence to antiretroviral therapy (coefficient estimate -0.43, 95% CrI -0.75 to -0.11) and viral suppression (-0.48; -0.84 to -0.12), suggesting that the effects of interventions wane over time.

Interpretation: Several interventions can improve adherence and viral suppression; generally, their estimated effects were modest and waned over time.

Abstract access  

Editor’s notes: Maintaining adherence to self-administered medications is difficult. On average, people who are prescribed medications for chronic diseases take fewer than half the prescribed doses. Evidence suggests that in most settings adherence to antiretroviral therapy (ART) is better than this, but there will always be people that struggle to maintain the high levels of adherence required for durable virologic suppression. In this analysis, there was some evidence that specific activities or combinations of activities improved virologic suppression. However, the effect sizes were small and when the analysis was confined to studies in low-income and middle-income countries, there was no evidence to suggest an effect on virologic suppression. Overall the evidence to support any particular activity or combination of activities was not compelling.     

Findings from this analysis have been incorporated into most recent consolidated ART guidelines from the World Health Organization. Trying to summarize complex evidence in this way creates many challenges. Trials were conducted in different populations. Some with all people starting ART, others with people considered to have high risk of suboptimal adherence, and others with people who already had adherence problems. The trials also naturally would have differed in content and quality of the usual package of care to support adherence (the comparator for most programme). 60% of the trials were conducted exclusively in the United States, while others were conducted across different settings.

These are just some of the things that make it difficult to synthesize this evidence into guidance that can be applicable to people living with HIV worldwide. HIV programmes in countries have to decide whether or not to adopt any of these activities that are recommended by WHO on the basis of relatively weak evidence. Would we expect activities aimed at improving adherence to be generalizable across different settings? One might argue probably not. Adherence is a multifactorial, dynamic process and there is unlikely to be a ‘one size fits all’ approach to supporting adherence. In the absence of better evidence for any specific activity, we should perhaps focus on improving the quality of the basic package of adherence support offered to all people receiving ART, while also developing better ways to identify when certain people might benefit from enhanced support.        

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Improving programmes: a thematic synthesis of qualitative studies of treatment adherence programmes

Barriers and facilitators of interventions for improving antiretroviral therapy adherence: a systematic review of global qualitative evidence.

Ma Q, Tso LS, Rich ZC, Hall BJ, Beanland R, Li H, Lackey M, Hu F, Cai W, Doherty M, Tucker JD. J Int AIDS Soc. 2016 Oct 17;19(1):21166. doi: 10.7448/IAS.19.1.21166. eCollection 2016.

Introduction: Qualitative research on antiretroviral therapy (ART) adherence interventions can provide a deeper understanding of intervention facilitators and barriers. This systematic review aims to synthesize qualitative evidence of interventions for improving ART adherence and to inform patient-centred policymaking.

Methods: We searched 19 databases to identify studies presenting primary qualitative data on the experiences, attitudes and acceptability of interventions to improve ART adherence among PLHIV and treatment providers. We used thematic synthesis to synthesize qualitative evidence and the CERQual (Confidence in the Evidence from Reviews of Qualitative Research) approach to assess the confidence of review findings.

Results: Of 2982 references identified, a total of 31 studies from 17 countries were included. Twelve studies were conducted in high-income countries, 13 in middle-income countries and six in low-income countries. Study populations focused on adults living with HIV (21 studies, n=1025), children living with HIV (two studies, n=46), adolescents living with HIV (four studies, n=70) and pregnant women living with HIV (one study, n=79). Twenty-three studies examined PLHIV perspectives and 13 studies examined healthcare provider perspectives. We identified six themes related to types of interventions, including task shifting, education, mobile phone text messaging, directly observed therapy, medical professional outreach and complex interventions. We also identified five cross-cutting themes, including strengthening social relationships, ensuring confidentiality, empowerment of PLHIV, compensation and integrating religious beliefs into interventions. Our qualitative evidence suggests that strengthening PLHIV social relationships, PLHIV empowerment and developing culturally appropriate interventions may facilitate adherence interventions. Our study indicates that potential barriers are inadequate training and compensation for lay health workers and inadvertent disclosure of serostatus by participating in the intervention.

Conclusions: Our study evaluated adherence interventions based on qualitative data from PLHIV and health providers. The study underlines the importance of incorporating social and cultural factors into the design and implementation of interventions. Further qualitative research is needed to evaluate ART adherence interventions.

Abstract  Full-text [free] access 

Editor’s notes: This is a review of studies using qualitative methods to explore the experiences of people living with HIV and healthcare providers involved in programmes to support antiretroviral treatment adherence. The thematic synthesis is presented in two ways. First, the reviewed studies are categorised by types of adherence programmes, such as task shifting, education, or directly observed therapy. Secondly, the authors present themes that are common across all reviewed studies. These include: the benefits and challenges of employing lay healthcare workers; the need to maintain confidentiality in adherence programmes; the benefits of supporting empowerment and social relationships for people living with HIV; and the need for culturally appropriate information and practice. Overall the review illustrates that adherence programmes can have more impact if they address confidentiality, strengthen social ties among people living with HIV and their communities; provide adequate compensation and training for lay healthcare workers; and sensitively reflect local social, cultural and religious norms and beliefs. 

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