Articles tagged as "HIV modelling"

Cryptoccal meningitis – the unacceptable consequence of leaving people behind during ART scale up

Editor’s notes: Cryptococcal meningitis is a severe disease that occurs in people with advanced immune suppression.  Its occurrence is an indicator that an HIV treatment programme is not working well, as it is rare in people whose CD4 count is above 100 cells per microlitre.  Rajasingham and colleagues have tried to estimate the current burden of disease.  This is not straightforward, as the number and proportion of people with advanced HIV disease is changing with the increasing scale up of antiretroviral therapy and earlier HIV diagnosis.  Nonetheless, severe immune suppression still occurs in those whose HIV infection remains undiagnosed or is diagnosed too late; among those who are not started on effective ARVs promptly and among those in whom ART fails and who are not managed effectively by the ART treatment programme.  The authors estimate that there could be more than 180 000 deaths from cryptococcal meningitis with the large majority (136 000) in Africa.  This makes Cryptococcus responsible for more than 15% of HIV-related deaths, second only to tuberculosis as a documented cause.  The authors emphasize the need for earlier diagnosis of HIV and better linkage to quality care programmes.  In the meantime, there are also advances in the screening, prophylaxis and treatment of Cryptococcus itself, which require investment in laboratory services and affordable medicines that can save lives until the effects of good ART improves the immune status.

Cassim and colleagues have developed a novel approach to costing different approaches to the roll out of technology for screening for cryptococcal antigen in the blood of people with advanced HIV infection.  Depending on the numbers of samples to be tested in the laboratory, a mix of single use lateral flow assays and automated enzyme immunoassays makes most sense.  The aim is to allow the more cost-effective high-volume sites to subsidize the low volume sites in order to ensure that as many people living with advanced HIV infection as possible can be screened.

Global burden of disease of HIV-associated cryptococcal meningitis: an updated analysis

Rajasingham R, Smith RM, Park BJ, Jarvis JN, Govender NP, Chiller TM, Denning DW, Loyse A, Boulware DR. Lancet Infect Dis. 2017 Aug;17(8):873-881. doi: 10.1016/S1473-3099(17)30243-8. Epub 2017 May 5.

Background: Cryptococcus is the most common cause of meningitis in adults living with HIV in sub-Saharan Africa. Global burden estimates are crucial to guide prevention strategies and to determine treatment needs, and we aimed to provide an updated estimate of global incidence of HIV-associated cryptococcal disease.

Methods: We used 2014 Joint UN Programme on HIV and AIDS estimates of adults (aged >15 years) with HIV and antiretroviral therapy (ART) coverage. Estimates of CD4 less than 100 cells per μL, virological failure incidence, and loss to follow-up were from published multinational cohorts in low-income and middle-income countries. We calculated those at risk for cryptococcal infection, specifically those with CD4 less than 100 cells/μL not on ART, and those with CD4 less than 100 cells per μL on ART but lost to follow-up or with virological failure. Cryptococcal antigenaemia prevalence by country was derived from 46 studies globally. Based on cryptococcal antigenaemia prevalence in each country and region, we estimated the annual numbers of people who are developing and dying from cryptococcal meningitis.

Findings: We estimated an average global cryptococcal antigenaemia prevalence of 6·0% (95% CI 5·8-6·2) among people with a CD4 cell count of less than 100 cells per μL, with 278 000 (95% CI 195 500-340 600) people positive for cryptococcal antigen globally and 223 100 (95% CI 150 600-282 400) incident cases of cryptococcal meningitis globally in 2014. Sub-Saharan Africa accounted for 73% of the estimated cryptococcal meningitis cases in 2014 (162 500 cases [95% CI 113 600-193 900]). Annual global deaths from cryptococcal meningitis were estimated at 181 100 (95% CI 119 400-234 300), with 135 900 (75%; [95% CI 93 900-163 900]) deaths in sub-Saharan Africa. Globally, cryptococcal meningitis was responsible for 15% of AIDS-related deaths (95% CI 10-19).

Interpretation: Our analysis highlights the substantial ongoing burden of HIV-associated cryptococcal disease, primarily in sub-Saharan Africa. Cryptococcal meningitis is a metric of HIV treatment programme failure; timely HIV testing and rapid linkage to care remain an urgent priority.

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Estimating the cost-per-result of a national reflexed cryptococcal antigenaemia screening program: Forecasting the impact of potential HIV guideline changes and treatment goals

Cassim N, Coetzee LM, Schnippel K, Glencross DK. PLoS One. 2017 Aug 22;12(8):e0182154. doi: 10.1371/journal.pone.0182154. eCollection 2017.

Introduction: During 2016, the National Health Laboratory Service (NHLS) introduced laboratory-based reflexed Cryptococcal antigen (CrAg) screening to detect early Cryptococcal disease in immunosuppressed HIV+ patients with a confirmed CD4 count of 100 cells/μl or less.

Objective: The aim of this study was to assess cost-per-result of a national screening program across different tiers of laboratory service, with variable daily CrAg test volumes. The impact of potential ART treatment guideline and treatment target changes on CrAg volumes, platform choice and laboratory workflow are considered.

Methods: CD4 data (with counts ≤ 100 cells/μl) from the fiscal year 2015/16 were extracted from the NHLS Corporate Date Warehouse and used to project anticipated daily CrAg testing volumes with appropriately-matched CrAg testing platforms allocated at each of 52 NHLS CD4 laboratories. A cost-per-result was calculated for four scenarios, including the existing service status quo (Scenario-I), and three other settings (as Scenarios II-IV) which were based on information from recent antiretroviral (ART) guidelines, District Health Information System (DHIS) data and UNAIDS 90/90/90 HIV/AIDS treatment targets. Scenario-II forecast CD4 testing offered only to new ART initiates recorded at DHIS. Scenario-III projected all patients notified as HIV+, but not yet on ART (recorded at DHIS) and Scenario-IV forecast CrAg screening in 90% of estimated HIV+ patients across South Africa (also DHIS). Stata was used to assess daily CrAg volumes at the 5th, 10th, 25th, 50th, 75th, 90th and 95th percentiles across 52 CD4-laboratories. Daily volumes were used to determine technical effort/ operator staff costs (% full time equivalent) and cost-per-result for all scenarios.

Results: Daily volumes ranged between 3 and 64 samples for Scenario-I at the 5th and 95th percentile. Similarly, daily volumes ranges of 1-12, 2-45 and 5-100 CrAg-directed samples were noted for Scenario's II, III and IV respectively. A cut-off of 30 CrAg tests per day defined use of either LFA or EIA platform. LFA cost-per-result ranged from $8.24 to $5.44 and EIA cost-per-result between $5.58 and $4.88 across the range of test volumes. The technical effort across scenarios ranged from 3.2-27.6% depending on test volumes and platform used.

Conclusion: The study reported the impact of programmatic testing requirements on varying CrAg test volumes that subsequently influenced choice of testing platform, laboratory workflow and cost-per-result. A novel percentiles approach is described that enables an overview of the cost-per-result across a national program. This approach facilitates cross-subsidisation of more expensive lower volume sites with cost-efficient, more centralized higher volume laboratories, mitigating against the risk of costing tests at a single site.

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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.

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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.

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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.

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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.

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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.


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.


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 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.


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.


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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H*V – can we do better for HIV, HBV and HCV if we all work together?

Editor’s notes: The Sustainable Development Goals (SDGs) signal a major shift in the way that the United Nations and her development partners aim to shape the next decades.  Whereas the Millennium Development Goals reinforced specific programmes for HIV, tuberculosis and malaria, the SDGs call for a more integrated approach to health and well-being and encourage integration and synergy wherever it makes sense.  Hepatitis is one obvious area in which better collaboration and coordination could yield benefits.  Hepatitis B (HBV) and C (HCV) viruses are both more common in some of the populations most affected by HIV.  HCV can now be cured with drugs that derive directly from the HIV portfolio, while some ARVs have a direct effect on HBV.

Rwanda is one of the first countries in sub-Saharan Africa to set up a control programme for viral hepatitis, building on the infrastructure established for HIV. Umutesi and colleagues report on results of screening almost 120 000 people living with HIV who entered care for markers of HBV and HCV.  Around 5000 people (4.3%) were identified with a positive Hepatitis B surface antigen and a similar number (4.6%) were found to have antibodies against HCV.  There was marked variation geographically with a range by district from 2%-11% for HBV, higher in more urban areas and in men.  For HCV the range was from 3%-8% and was higher in more rural areas, and also in men.  This study provides a good platform to estimate numbers of people who might need treatment and to plan the next steps in an integrated programme.

People who inject drugs are particularly severely affected by HCV, and so co-infection with both HIV and HCV is common in areas where both viruses circulate.  Some estimates from Ho Chi Minh City in Viet Nam suggest that more than 40% of people who inject drugs are living with HIV and that essentially all of these people are also co-infected with HCV.  Birger R and colleagues developed a mathematical model to explore the likely impact of interventions aimed at HIV, HCV or broad harm reduction [with methadone maintenance treatment (MMT)] on future mortality and incidence of both infections.  While ART scale up reduces HIV incidence and mortality, it has no effect on HCV.  MMT is effective at reducing incidence of both HIV and HCV (and has morbidity and mortality benefits beyond these viruses).  However, MMT does not help the many people already living with HCV and so has little effect on HCV related mortality. So the model is clear that treatment for HCV needs to be an important part of a combined programme and that we urgently need to find ways to reduce the price of directly acting antivirals if we are to save more Vietnamese lives.

Haldane and colleagues have also focused on this intersection between HIV and substance use services.  They carried out a systematic review to understand the models and implications of integration of service delivery.  The authors expand their typology of integration models considering the point of entry of the client, and the degree to which services are co-located and delivered.  Integration can be considered as “clinical”, “service” or “systems”.  The first two can operate at the micro or meso level meaning that individual staff can deal with both situations, or that staff are trained to provide appropriate referrals.  Systems level integration operates at a macro level and implies that programmes for each service make collaborations and coordinate in ways that may affect staffing, funding and fragmentation of services. Although there are theoretical advantages to coordination and integration (as shown by the mathematical model above), there are few good empirical studies of integrated service delivery reported outside the USA.  The authors considered that most of the intervention studies had a risk of bias in the interpretation of their impact, although all demonstrated positive changes in outcomes.  Furthermore, almost all the studies focussed on integration at the clinic or individual provider level (meso or micro) rather than addressing the larger systemic challenges that we need to consider.  If we are to achieve the ideals laid out in the Sustainable Development Goals, we will need to overcome some of these systemic challenges, particularly for populations that are criminalized and marginalized by many of the public services.

Prevalence of hepatitis B and C infection in persons living with HIV enrolled in care in Rwanda.

Umutesi J, Simmons B, Makuza JD, Dushimiyimana D, Mbituyumuremyi A, Uwimana JM, Ford N, Mills EJ, Nsanzimana S. BMC Infect Dis. 2017 May 2;17(1):315. doi: 10.1186/s12879-017-2422-9.

Background: Hepatitis B (HBV) and C (HCV) are important causes of morbidity and mortality in people living with human immunodeficiency virus (HIV). The burden of these co-infections in sub-Saharan Africa is still unclear. We estimated the prevalence of the hepatitis B surface antigen (HBsAg) and hepatitis C antibody (HCVAb) among HIV-infected individuals in Rwanda and identified factors associated with infection.

Methods: Between January 2016 and June 2016, we performed systematic screening for HBsAg and HCVAb among HIV-positive individuals enrolled at public and private HIV facilities across Rwanda. Results were analyzed to determine marker prevalence and variability by demographic factors.

Results: Overall, among 117 258 individuals tested, the prevalence of HBsAg and HCVAb was 4.3% (95% confidence interval [CI] (4.2-4.4) and 4.6% (95% CI 4.5-4.7) respectively; 182 (0.2%) HIV+ individuals were co-infected with HBsAg and HCVAb. Prevalence was higher in males (HBsAg, 5.4% [5.1-5.6] vs. 3.7% [3.5-3.8]; HCVAb, 5.0% [4.8-5.2] vs. 4.4% [4.3-4.6]) and increased with age; HCVAb prevalence was significantly higher in people aged ≥65 years (17.8% [16.4-19.2]). Prevalence varied geographically.

Conclusion: HBV and HCV co-infections are common among HIV-infected individuals in Rwanda. It is important that viral hepatitis prevention and treatment activities are scaled-up to control further transmission and reduce the burden in this population. Particular efforts should be made to conduct targeted screening of males and the older population. Further assessment is required to determine rates of HBV and HCV chronicity among HIV-infected individuals and identify effective strategies to link individuals to care and treatment.

Abstract  Full-text [free] access

The impact of HCV therapy in a high HIV-HCV prevalence population: A modeling study on people who inject drugs in Ho Chi Minh City, Vietnam.

Birger RB, Le T, Kouyos RD, Grenfell BT, Hallett TB. PLoS One. 2017 May 11;12(5):e0177195. doi: 10.1371/journal.pone.0177195. eCollection 2017.

Background: Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV) coinfection is a major global health problem especially among people who inject drugs (PWID), with significant clinical implications. Mathematical models have been used to great effect to shape HIV care, but few have been proposed for HIV/HCV.

Methods: We constructed a deterministic compartmental ODE model that incorporated layers for HIV disease progression, HCV disease progression and PWID demography. Antiretroviral therapy (ART) and Methadone Maintenance Therapy (MMT) scale-ups were modeled as from 2016 and projected forward 10 years. HCV treatment roll-out was modeled beginning in 2026, after a variety of MMT scale-up scenarios, and projected forward 10 years.

Results: Our results indicate that scale-up of ART has a major impact on HIV though not on HCV burden. MMT scale-up has an impact on incidence of both infections. HCV treatment roll-out has a measurable impact on reductions of deaths, increasing multifold the mortality reductions afforded by just ART/MMT scale-ups.

Conclusion: HCV treatment roll-out can have major and long-lasting effects on averting PWID deaths on top of those averted by ART/MMT scale-up. Efficient intervention scale-up of HCV alongside HIV interventions is critical in Vietnam.

Abstract  Full-text [free] access 

Integrating HIV and substance use services: a systematic review

Haldane V, Cervero-Liceras F, Chuah FL, Ong SE, Murphy G, Sigfrid L, Watt N, Balabanova D, Hogarth S, Maimaris W, Buse K, Piot P, McKee M, Perel P, Legido-Quigley H. Journal of the International AIDS Society. 2017 May 30;20(1).

Introduction: Substance use is an important risk factor for HIV, with both concentrated in certain vulnerable and marginalized populations. Although their management differs, there may be opportunities to integrate services for substance use and HIV. In this paper we systematically review evidence from studies that sought to integrate care for people living with HIV and substance use problems.

Methods: Studies were included if they evaluated service integration for substance use and HIV. We searched multiple databases from inception until October 2015. Articles were screened independently by two reviewers and assessed for risk of bias.

Results and discussion: 11 057 records were identified, with 7616 after removal of duplicates. After screening titles and abstracts, 51 met the inclusion criteria. Integration models were categorized by location (HIV, substance use and other facilities), level of integration from micro (integrated care delivered to individuals) to macro (system level integrations) and degree of integration from least (screening and counselling only) to most (care for HIV, substance use and/or other illnesses at the same facility). Most reported descriptive or cohort studies; in four randomized control trials integrated activities improved patient outcomes. There is potential for integrating services at all facility types, including mobile health services. While services offering screening only can achieve synergies, there are benefits from delivering integrated treatment for HIV and substance use, including ease of referral to other mental health and social services.

Conclusions: Our review used a wide range of databases and conference archives to increase representation of papers from low- and middle-income countries. Limitations include the overrepresentation of studies from the United States, and the descriptive nature of the majority of papers. The evidence reviewed shows that greater integration offers important benefits in both patient and service outcomes but further research and outcome reporting is needed to better understand innovative and holistic care models at the complex intersection of substance use and HIV services.

Abstract  Full-text [free] access

Africa, Asia, Europe, Northern America
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Benefits of including males living with HIV in voluntary medical male circumcision - modelling analysis

Could circumcision of HIV-positive males benefit voluntary medical male circumcision programs in Africa? Mathematical modeling analysis.

Awad SF, Sgaier SK, Lau FK, Mohamoud YA, Tambatamba BC, Kripke KE, Thomas AG, Bock N, Reed JB, Njeuhmeli E, Abu-Raddad LJ. PLoS One. 2017 Jan 24;12(1):e0170641. doi: 10.1371/journal.pone.0170641. eCollection 2017.

Background: The epidemiological and programmatic implications of inclusivity of HIV-positive males in voluntary medical male circumcision (VMMC) programs are uncertain. We modeled these implications using Zambia as an illustrative example.

Methods and findings: We used the Age-Structured Mathematical (ASM) model to evaluate, over an intermediate horizon (2010-2025), the effectiveness (number of VMMCs needed to avert one HIV infection) of VMMC scale-up scenarios with varying proportions of HIV-positive males. The model was calibrated by fitting to HIV prevalence time trend data from 1990 to 2014. We assumed that inclusivity of HIV positive males may benefit VMMC programs by increasing VMMC uptake among higher risk males, or by circumcision reducing HIV male-to-female transmission risk. All analyses were generated assuming no further antiretroviral therapy (ART) scale-up. The number of VMMCs needed to avert one HIV infection was projected to increase from 12.2 VMMCs per HIV infection averted, in a program that circumcises only HIV-negative males, to 14.0, in a program that includes HIV-positive males. The proportion of HIV-positive males was based on their representation in the population (e.g. 12.6% of those circumcised in 2010 would be HIV-positive based on HIV prevalence among males of 12.6% in 2010). However, if a program that only reaches out to HIV-negative males is associated with 20% lower uptake among higher-risk males, the effectiveness would be 13.2 VMMCs per infection averted. If improved inclusivity of HIV-positive males is associated with 20% higher uptake among higher-risk males, the effectiveness would be 12.4. As the assumed VMMC efficacy against male-to-female HIV transmission was increased from 0% to 20% and 46%, the effectiveness of circumcising regardless of HIV status improved from 14.0 to 11.5 and 9.1, respectively. The reduction in the HIV incidence rate among females increased accordingly, from 24.7% to 34.8% and 50.4%, respectively.

Conclusion: Improving inclusivity of males in VMMC programs regardless of HIV status increases VMMC effectiveness, if there is moderate increase in VMMC uptake among higher-risk males and/or if there is moderate efficacy for VMMC against male-to-female transmission. In these circumstances, VMMC programs can reduce the HIV incidence rate in males by nearly as much as expected by some ART programs, and additionally, females can benefit from the intervention nearly as much as males.

Abstract  Full-text [free] access

Editor’s notes: Evidence from randomised control trials and modelling studies suggest that voluntary male medical circumcision (VMMC) is a cost-effective HIV prevention programme. A deterministic compartmental age structured HIV model was used to assess benefits of including HIV positive males in VMMC programmes. The HIV model was parameterized using HIV biological and behavioural data for sub-Saharan Africa.  The model was fit to HIV prevalence for Zambia in the years between 1990 and 2014. The model used baseline circumcision coverages from Zambia Demographic and Health Survey 2007. The authors analysed the model for three VMMC programme scenarios; circumcising HIV negative males only, circumcising both HIV negative and HIV positive males, and circumcising males regardless of their HIV status. Sensitivity analysis was conducted to ascertain the robustness of key model assumptions on the study findings. The findings from the study suggest that, improving the inclusivity of all males is likely to improve the effectiveness of VMMC programmes.  This will be the case if there is moderate increase in uptake among higher-risk males and/or moderate VMMC efficacy in preventing male-to-female transmission. This is a very interesting modelling study which gives insights to policymakers on factors to consider in designing VMMC programmes. 

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Accurate country-level data necessary to inform HIV incidence estimates

Estimates of global, regional, and national incidence, prevalence, and mortality of HIV, 1980-2015: the Global Burden of Disease Study 2015.

Wang H, Wolock TM, Carter A, Nguyen G, Kyu HH, Gakidou E, Hay SI, Mills EJ, Trickey A, Msemburi W, Coates MM, Mooney MD, Fraser MS, Sligar A, Salomon J, Larson HJ, Friedman J, Abajobir AA, Abate KH, Abbas KM, Razek MM, Abd-Allah F, Abdulle AM, Abera SF, Abubakar I, Abu-Raddad LJ, Abu-Rmeileh NM, Abyu GY, Adebiyi AO, Adedeji IA, Adelekan AL, Adofo K, Adou AK, Ajala ON, Akinyemiju TF, Akseer N, Lami FH, Al-Aly Z, Alam K, Alam NK, Alasfoor D, Aldhahri SF, Aldridge RW, Alegretti MA, Aleman AV, Alemu ZA, Alfonso-Cristancho R, Ali R, Alkerwi A, Alla F, Mohammad R, Al-Raddadi S, Alsharif U, Alvarez E, Alvis-Guzman N, Amare AT, Amberbir A, Amegah AK, Ammar W, Amrock SM, Antonio CA, Anwari P, Arnlov J, Artaman A, Asayesh H, Asghar RJ, Assadi R, Atique S, Atkins LS, Avokpaho EF, Awasthi A, Quintanilla BP, Bacha U, Badawi A, Barac A, Barnighausen T, Basu A, Bayou TA, Bayou YT, Bazargan-Hejazi S, Beardsley J, Bedi N, Bennett DA, Bensenor IM, Betsu BD, Beyene AS, Bhatia E, Bhutta ZA, Biadgilign S, Bikbov B, Birlik SM, Bisanzio D, Brainin M, Brazinova A, Breitborde NJ, Brown A, Burch M, Butt ZA, Campuzano JC, Cardenas R, Carrero JJ, Castaneda-Orjuela CA, Rivas JC, Catala-Lopez F, Chang HY, Chang JC, Chavan L, Chen W, Chiang PP, Chibalabala M, Chisumpa VH, Choi JY, Christopher DJ, Ciobanu LG, Cooper C, Dahiru T, Damtew SA, Dandona L, Dandona R, das Neves J, de Jager P, De Leo D, Degenhardt L, Dellavalle RP, Deribe K, Deribew A, Des Jarlais DC, Dharmaratne SD, Ding EL, Doshi PP, Driscoll TR, Dubey M, Elshrek YM, Elyazar I, Endries AY, Ermakov SP, Eshrati B, Esteghamati A, Faghmous ID, Farinha CS, Faro A, Farvid MS, Farzadfar F, Fereshtehnejad SM, Fernandes JC, Fischer F, Fitchett JR, Foigt N, Fullman N, Furst T, Gankpe FG, Gebre T, Gebremedhin AT, Gebru AA, Geleijnse JM, Gessner BD, Gething PW, Ghiwot TT, Giroud M, Gishu MD, Glaser E, Goenka S, Goodridge A, Gopalani SV, Goto A, Gugnani HC, Guimaraes MD, Gupta R, Gupta R, Gupta V, Haagsma J, Hafezi-Nejad N, Hagan H, Hailu GB, Hamadeh RR, Hamidi S, Hammami M, Hankey GJ, Hao Y, Harb HL, Harikrishnan S, Haro JM, Harun KM, Havmoeller R, Hedayati MT, Heredia-Pi IB, Hoek HW, Horino M, Horita N, Hosgood HD, Hoy DG, Hsairi M, Hu G, Huang H, Huang JJ, Iburg KM, Idrisov BT, Innos K, Iyer VJ, Jacobsen KH, Jahanmehr N, Jakovljevic MB, Javanbakht M, Jayatilleke AU, Jeemon P, Jha V, Jiang G, Jiang Y, Jibat T, Jonas JB, Kabir Z, Kamal R, Kan H, Karch A, Karema CK, Karletsos D, Kasaeian A, Kaul A, Kawakami N, Kayibanda JF, Keiyoro PN, Kemp AH, Kengne AP, Kesavachandran CN, Khader YS, Khalil I, Khan AR, Khan EA, Khang YH, Khubchandani J, Kim YJ, Kinfu Y, Kivipelto M, Kokubo Y, Kosen S, Koul PA, Koyanagi A, Defo BK, Bicer BK, Kulkarni VS, Kumar GA, Lal DK, Lam H, Lam JO, Langan SM, Lansingh VC, Larsson A, Leigh J, Leung R, Li Y, Lim SS, Lipshultz SE, Liu S, Lloyd BK, Logroscino G, Lotufo PA, Lunevicius R, Razek HM, Mahdavi M, Majdan M, Majeed A, Makhlouf C, Malekzadeh R, Mapoma CC, Marcenes W, Martinez-Raga J, Marzan MB, Masiye F, Mason-Jones AJ, Mayosi BM, McKee M, Meaney PA, Mehndiratta MM, Mekonnen AB, Melaku YA, Memiah P, Memish ZA, Mendoza W, Meretoja A, Meretoja TJ, Mhimbira FA, Miller TR, Mikesell J, Mirarefin M, Mohammad KA, Mohammed S, Mokdad AH, Monasta L, Moradi-Lakeh M, Mori R, Mueller UO, Murimira B, Murthy GV, Naheed A, Naldi L, Nangia V, Nash D, Nawaz H, Nejjari C, Ngalesoni FN, de Dieu Ngirabega J, Nguyen QL, Nisar MI, Norheim OF, Norman RE, Nyakarahuka L, Ogbo FA, Oh IH, Ojelabi FA, Olusanya BO, Olusanya JO, Opio JN, Oren E, Ota E, Padukudru MA, Park HY, Park JH, Patil ST, Patten SB, Paul VK, Pearson K, Peprah EK, Pereira CC, Perico N, Pesudovs K, Petzold M, Phillips MR, Pillay JD, Plass D, Polinder S, Pourmalek F, Prokop DM, Qorbani M, Rafay A, Rahimi K, Rahimi-Movaghar V, Rahman M, Rahman MH, Rahman SU, Rai RK, Rajsic S, Ram U, Rana SM, Rao PV, Remuzzi G, Rojas-Rueda D, Ronfani L, Roshandel G, Roy A, Ruhago GM, Saeedi MY, Sagar R, Saleh MM, Sanabria JR, Santos IS, Sarmiento-Suarez R, Sartorius B, Sawhney M, Schutte AE, Schwebel DC, Seedat S, Sepanlou SG, Servan-Mori EE, Shaikh. Lancet HIV. 2016 Aug;3(8):e361-87. doi: 10.1016/S2352-3018(16)30087-X. Epub 2016 Jul 19.

Background: Timely assessment of the burden of HIV/AIDS is essential for policy setting and programme evaluation. In this report from the Global Burden of Disease Study 2015 (GBD 2015), we provide national estimates of levels and trends of HIV/AIDS incidence, prevalence, coverage of antiretroviral therapy (ART), and mortality for 195 countries and territories from 1980 to 2015.

Methods: For countries without high-quality vital registration data, we estimated prevalence and incidence with data from antenatal care clinics and population-based seroprevalence surveys, and with assumptions by age and sex on initial CD4 distribution at infection, CD4 progression rates (probability of progression from higher to lower CD4 cell-count category), on and off antiretroviral therapy (ART) mortality, and mortality from all other causes. Our estimation strategy links the GBD 2015 assessment of all-cause mortality and estimation of incidence and prevalence so that for each draw from the uncertainty distribution all assumptions used in each step are internally consistent. We estimated incidence, prevalence, and death with GBD versions of the Estimation and Projection Package (EPP) and Spectrum software originally developed by the Joint United Nations Programme on HIV/AIDS (UNAIDS). We used an open-source version of EPP and recoded Spectrum for speed, and used updated assumptions from systematic reviews of the literature and GBD demographic data. For countries with high-quality vital registration data, we developed the cohort incidence bias adjustment model to estimate HIV incidence and prevalence largely from the number of deaths caused by HIV recorded in cause-of-death statistics. We corrected these statistics for garbage coding and HIV misclassification.

Findings: Global HIV incidence reached its peak in 1997, at 3.3 million new infections (95% uncertainty interval [UI] 3.1-3.4 million). Annual incidence has stayed relatively constant at about 2.6 million per year (range 2.5-2.8 million) since 2005, after a period of fast decline between 1997 and 2005. The number of people living with HIV/AIDS has been steadily increasing and reached 38.8 million (95% UI 37.6-40.4 million) in 2015. At the same time, HIV/AIDS mortality has been declining at a steady pace, from a peak of 1.8 million deaths (95% UI 1.7-1.9 million) in 2005, to 1.2 million deaths (1.1-1.3 million) in 2015. We recorded substantial heterogeneity in the levels and trends of HIV/AIDS across countries. Although many countries have experienced decreases in HIV/AIDS mortality and in annual new infections, other countries have had slowdowns or increases in rates of change in annual new infections.

Interpretation: Scale-up of ART and prevention of mother-to-child transmission has been one of the great successes of global health in the past two decades. However, in the past decade, progress in reducing new infections has been slow, development assistance for health devoted to HIV has stagnated, and resources for health in low-income countries have grown slowly. Achievement of the new ambitious goals for HIV enshrined in Sustainable Development Goal 3 and the 90-90-90 UNAIDS targets will be challenging, and will need continued efforts from governments and international agencies in the next 15 years to end AIDS by 2030.

Abstract  Full-text [free] access

Editor’s notes: The global estimates for HIV incidence, prevalence, and deaths produced by the Global Burden of Disease (GBD) mathematical modelling approach for 2015 are somewhat higher than those published by UNAIDS in June 2016 prior to the International Conference on AIDS held in Durban in July. Both GBD and UNAIDS agree that as the scale-up of antiretroviral treatment (ART) continues, HIV-associated mortality is declining with the result that HIV prevalence is rising as the number of people living with HIV continues to grow. The metric of critical interest to policy makers and programme planners is HIV incidence, the number of new infections. Each new infection means ART for life, starting from HIV diagnosis now rather than later in disease progression. Both GBD and UNAIDS estimates suggest that globally annual HIV incidence stopped declining after 2005 and has remained persistently high at 2.5 million (2.2-2.7 million) according to GDB and 2.1 million (1.8-2.4 million) according to UNAIDS. Where the estimates differ is at country level, precisely where they can make the most difference to decision making. GBD estimates for HIV incidence for countries in the regions of northern America, Europe, Australasia, and central Asia are significantly lower than the reported numbers of newly diagnosed cases (see the comparison table in the Lancet commentary by Supervie and Costagliola. For example, 85 252 people were newly diagnosed with HIV in the Russian federation in 2014 whereas the GBD estimate for people newly acquiring HIV in 2015 was only 57 340, albeit with a wide range of uncertainly. For the United States of America, the uncertainly bounds around the GBD estimate of 23 040 do not include 44,073, the number of newly diagnosed cases. Furthermore, new diagnoses likely underestimate actual HIV incidence as they include people who acquired HIV in previous years. Estimates for some high prevalence countries are significantly higher than those produced by those countries with UNAIDS support. For example, illustrates South Africa as having 380 000 (330 000-430 000) new infections while GBD estimates 529 670 (440 940 to 630 390). Modelling estimates are simply estimates but they cannot be confirmatory or even complementary when they are so different. UNAIDS and IHME (GBD) are already working to understand the differences in the two mathematical modelling approaches - their methodologies, parameters, and assumptions - in order to explain important discrepancies at country level. More importantly, improved data collection by countries of the numbers of HIV diagnoses, people accessing and staying on ART, and the proportion of people living with HIV who achieve viral suppression is necessary to monitor progress towards the UNAIDS 90-90-90 treatment target. Enhanced clinical and epidemiological surveillance systems are also key to the creation of more accurate estimates of country HIV incidence, the metric that reflects HIV prevention programme progress and informs budget allocations and programme planning for HIV treatment. 

195 countries
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Using mathematical models to understand the impact of universal therapy for HIV serodiscordant couples

Estimating the impact of universal antiretroviral therapy for HIV serodiscordant couples through home HIV testing: insights from mathematical models.

Roberts ST, Khanna AS, Barnabas RV, Goodreau SM, Baeten JM, Celum C, Cassels S. J Int AIDS Soc. 2016 May 11;19(1):20864. doi: 10.7448/IAS.19.1.20864. eCollection 2016.

Introduction: Antiretroviral therapy (ART) prevents HIV transmission within HIV serodiscordant couples (SDCs), but slow implementation and low uptake has limited its impact on population-level HIV incidence. Home HIV testing and counselling (HTC) campaigns could increase ART uptake among SDCs by incorporating couples' testing and ART referral. We estimated the reduction in adult HIV incidence achieved by incorporating universal ART for SDCs into home HTC campaigns in KwaZulu-Natal (KZN), South Africa, and southwestern (SW) Uganda.

Methods: We constructed dynamic, stochastic, agent-based network models for each region. We compared adult HIV incidence after 10 years under three scenarios: (1) "Current Practice," (2) "Home HTC" with linkage to ART for eligible persons (CD4 <350) and (3) "ART for SDCs" regardless of CD4, delivered alongside home HTC.

Results: ART for SDCs reduced HIV incidence by 38% versus Home HTC: from 1.12 (95% CI: 0.98-1.26) to 0.68 (0.54-0.82) cases per 100 person-years (py) in KZN, and from 0.56 (0.50-0.62) to 0.35 (0.30-0.39) cases per 100 py in SW Uganda. A quarter of incident HIV infections were averted over 10 years, and the proportion of virally suppressed HIV-positive persons increased approximately 15%.

Conclusions: Using home HTC to identify SDCs and deliver universal ART could avert substantially more new HIV infections than home HTC alone, with a smaller number needed to treat to prevent new HIV infections. Scale-up of home HTC will not diminish the effectiveness of targeting SDCs for treatment. Increasing rates of couples' testing, disclosure, and linkage to care is an efficient way to increase the impact of home HTC interventions on HIV incidence.

Abstract  Full-text [free] access 

Editor’s notes: Delivering effective and efficient HIV prevention programmes to serodiscordant couples continues to be a challenge. The study used a dynamic stochastic agent–based network model to estimate the impact of universal antiretroviral therapy for serodiscordant couples. The authors examined the scaling up of antiretroviral therapy through home HIV testing and counselling in KwaZulu-Natal in South Africa and South-western Uganda. Data from South Africa and Uganda were used to compare three HIV programme scenarios. These included routine antiretroviral therapy delivery in the general population, routine antiretroviral therapy  delivery in the general population and home HIV testing and counselling campaigns, and home HIV testing and counselling and delivery of antiretroviral therapy to serodiscordant couples during home HIV testing and counselling campaigns.  The authors found that a combination of HIV prevention programmes that provide universal antiretroviral therapy for serodiscordant couples in the context of home HIV testing and counselling had more impact in reducing HIV incidence. The study demonstrated that home HIV testing and counselling and linkage to care HIV programmes can substantially reduce HIV incidence in South Africa and Uganda. This is a very interesting and well-designed modelling study which incorporates the effects of partnership dynamics in estimating the population level impact of HIV programmes.

HIV modelling
South Africa, Uganda
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How can HIV resources be best used to avert as many infections as possible?

Using geospatial modelling to optimize the rollout of antiretroviral-based pre-exposure HIV interventions in sub-Saharan Africa.

Gerberry DJ, Wagner BG, Garcia-Lerma JG, Heneine W, Blower S. Nat Commun. 2014 Dec 2;5:5454. doi: 10.1038/ncomms6454.

Antiretroviral (ARV)-based pre-exposure HIV interventions may soon be rolled out in resource-constrained sub-Saharan African countries, but rollout plans have yet to be designed. Here we use geospatial modelling and optimization techniques to compare two rollout plans for ARV-based microbicides in South Africa: a utilitarian plan that minimizes incidence by using geographic targeting, and an egalitarian plan that maximizes geographic equity in access to interventions. We find significant geographic variation in the efficiency of interventions in reducing HIV transmission, and that efficiency increases disproportionately with increasing incidence. The utilitarian plan would result in considerable geographic inequity in access to interventions, but (by exploiting geographic variation in incidence) could prevent ~40% more infections than the egalitarian plan. Our results show that the geographic resource allocation decisions made at the beginning of a rollout, and the location where the rollout is initiated, will be crucial in determining the success of interventions in reducing HIV epidemics.

Abstract access

Editor’s notes: With the flatlining of HIV resources, it is becoming increasingly important to identify how best to maximise the impact of HIV programmes. This study used geospatial HIV modelling and optimisation to compare two potential rollout plans for antiretroviral based microbicides. One was based on egalitarian principles, where every community has an equal chance of accessing microbicides. The other was based on the utilitarian principles, where settings at greatest risk are prioritised. Assuming a fixed amount of resources, the impact of these two different rollout plans was compared. Using data from South Africa, the authors found that the geographic focusing at provincial level could prevent more infections in the first year of the rollout. The findings illustrate how decisions made about where new prevention technologies are first introduced at the start of a programme rollout can strongly influence the scale of their impact. In particular, it highlights that roll out strategies that first focus on the most vulnerable communities could have greatest impact. The modelling approach used in this study is applicable to other settings with geographic heterogeneity in the HIV epidemic, and could be used to inform the implementation and evaluation of other HIV prevention programmes.

HIV modelling
South Africa
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