Technology is advancing rapidly, but are we making the most of it?

Editor’s notes: HIV self-testing was a key area of discussion in the Paris IAS meeting [1].  UNITAID signed the next phase of the STAR Initiative [2] that is working with six countries in Southern Africa to transform the market for self-testing and understand the impact of different delivery systems.  The Bill and Melinda Gates Foundation are using their resources to lower prices of self-test kits.  Following WHO’s decision to prequalify an oral fluid test, many countries are including self-test commodities within their PEPFAR Country Operation Plans and Global Fund concept notes. WHO have issued guidance on self-testing and assisted partner notification [3]. So we can expect to see more and more self-tests out there in the field!

In Malawi, Choko et al. reported on qualitative research done prior to a cluster randomized trial that involves providing self-tests to women attending antenatal care (ANC) for them to take home to their partners.  Although couples are welcomed at ANC clinics and couple testing is certainly beneficial, many men still feel that the clinic is not a place for them.  As one participant said: “Considering what happens here at the ANC clinic, I don’t see my husband escorting me anymore because you find he is alone among many women and he has to listen to some things concerning birth. . . .”

In contrast, many women and men engaged in conversations about how providing self-test kits could help communication, stigma, privacy, control and time pressure among other aspects of involving men in HIV testing.  Some concerns were raised around violence and it is clear that this approach will suit some but not all couples, so it needs to be delivered in a way that respects autonomy with no coercion.

In a very different context, Jamil et al. have conducted a randomized trial among Australian gay men and men who have sex with men.  The trial enrolled “high risk” men who reported multiple partners and condomless sex over the past months.  A central premise of public health strategies to control the HIV epidemic is to find people who have acquired HIV as early as possible.  So the trial aimed to determine whether the offer of free oral fluid self-tests led to earlier testing and more frequent testing.  They found that compared with standard care, availability of free oral-fluid self-testing increased testing frequency both in men who had not tested recently and in men who had not tested at all in the past years. Importantly there was no decline in facility-based testing for HIV or sexually transmitted infections, which might have implied replacement.  The men commented that self-testing was highly acceptable and easy to do.

Self-tests are not a panacea.  Oral fluid tests do have a slightly lower sensitivity than blood based tests.  This may be important when HIV-antibody levels are not high, particularly in people taking ART (either as treatment or as PrEP), or early in the course of infection.  Furthermore, both oral fluid and blood based test rely on visual identification of bands on the test strip that may be faint, leading to some people assuming that they are negative or failing to see the positive band.  Curlin et al. examined the performance of oral fluid tests in people seroconverting to HIV during three specific trials.  They found a considerable number of false negative results and a long delay before some individuals became positive on oral fluid tests.  There was also a clear suggestion that some test operators were less good than others at performing the test and the possibility that one batch of the test kits were less sensitive.  Overall they concluded that “caution must be exercised when interpreting a negative oral fluid test in settings where acute infection is likely, and where PrEP use, ART induced viral suppression, or profound immunosuppression may result in low HIV-specific antibody titers.”  However, as an additional screening tool to be used in populations where many of whom are “missing” from the first 90 are to be found, self-tests have much to offer.  Many of these people will have acquired HIV some time ago and by definition will not be taking ART.  So the cautions raised by Curlin et al. may be less relevant for the primary intended purpose of self-tests.  Nonetheless, they make it very clear that oral fluid self-tests are not an appropriate technology to follow people on treatment or on PrEP.  Nor are they recommended for the diagnosis of acute infection.

While self-tests may increase the proportion of adults knowing their HIV status, different technology is needed for infants.  Nucleic acid amplification is used to detect pro-viral DNA or viral RNA in samples from infants.  The technology is more complex and often centralized, leading to delays and loss to follow up in mother-infant pairs.  Several systems now aim to provide testing close to the point of care and the evaluation of the SAMBA HIV-1 Qual Whole Blood Test from Ondiek et al. is an encouraging report.  Sensitivity and specificity were high (98.5% and 99.8% on 745 infant samples) and comparable to the standard approach used in centralized labs.  Samples from those with discrepant results were rechecked by assays based on multiple targets and suggested that the SAMBA test and the standard approach were each responsible for some of the few false positive and negatives seen.  The advantages of the SAMBA system is that it has been designed to be used in peripheral health systems.  All the reagents are freeze dried and stable without refrigeration. Turnaround time is approximately 2 hours with minimal sample handling once the sample is put into the machine.  Costs will still need to come down, but competition with other manufacturers may help.

The SAMBA technology that was evaluated is a qualitative assay aimed at diagnosis of infants.  A larger market is for viral load assays that are central to the monitoring of the effectiveness of HIV treatment and form the indicator for UNAIDS’s third 90.  However, at the moment viral load assays are still too expensive. As a result the optimal strategy for their use remains uncertain within programmes that have to make difficult decisions about where their limited resources should be spent.

Negoescu et al. have built an interesting model to explore the economic trade-offs between different frequencies of performing viral load assays.  More importantly they explore models of adapting the frequency of assays according to characteristics of the person taking ART.  People who have been on treatment for longer periods, or are older, or report fewer problems with adherence could be selected for less frequent assays.  This could save resources, without compromising health outcomes.  However, for countries like Uganda, which was used as the example to calibrate the model, the best approach seems to still be a viral load assay once per year, regardless of other factors.  And indeed, many resource limited countries are having to make difficult choices about how to allocate stretched budgets between expansion of access to viral load assays to the possible detriment of basic prevention programmes such as male circumcision and condoms.  As more resources become available (or as the cost of viral load assays fall) countries may well choose to do more frequent viral load assays.  The authors showed that monthly assays were more expensive but did (unsurprisingly) lead to benefits in terms of earlier detection of virological failure.  Given the renewed attention to drug resistance and the role of late detection of HIV treatment failure in propagating it, such models may become increasingly important.  Adapting the viral load assay frequency to the characteristics of the person taking HIV treatment could be a sensible approach in middle and higher income settings.

For some years, WHO has recommended that nucleic acid amplification should also be used as the first line test for tuberculosis among people living with HIV.  The GeneXpert® system has been taken up quite widely in many countries where HIV is common among people with tuberculosis, most notably in South Africa.  However, Hermans et al. remind us that technology is only one part of the solution.  Although there is no doubt that Xpert is considerably more sensitive than sputum microscopy and considerably quicker than mycobacterial culture, incorporating the technology into routine practice is not always straightforward.  At the Infectious Disease Institute in Kampala, Uganda [4], where there are well trained clinicians and better resources than in much of the rest of Uganda, Xpert was made available at no cost for the diagnosis of tuberculosis in a one stop combined HIV-TB clinic.  In a cohort of people living with HIV with symptoms suggestive of possible tuberculosis and whose sputum smear microscopy result was negative, many clinicians still preferred to treat on the basis of their clinical judgement and chest radiography.  Xpert™ was requested in less than half the patients.  Similar numbers of people were started on treatment for tuberculosis regardless of whether Xpert was requested (22% vs 21%).  And among those in whom an Xpert™ was performed, more were started on anti-tuberculosis treatment who had had a negative test than a positive one.  So it was not really clear that Xpert was useful in the diagnosis and management of HIV-related tuberculosis in this setting.  Xpert is not 100% sensitive, so many clinicians will choose to treat patients who might have tuberculosis regardless of the results of new technology.  Xpert also give a result that includes resistance to rifampicin, but this was not such a major issue in Kampala and was not an objective of this study.  Those treated without a confirmed test result were more likely to die during the next 12 months, but the authors point out that there are many possible reasons for this.  Many clinicians are aware of the high rates of undiagnosed tuberculosis found at autopsy in people with HIV. Thus, empirical treatment is often given to those who are critically unwell, even when there is no clear evidence of tuberculosis.

GeneXpert® was also the technology used in another study of tuberculosis contact tracing among school children in Swaziland (Ustero et al.).  Despite a rapid and extensive response to look for additional cases in schools where a confirmed case of tuberculosis had been found, no secondary cases were identified.  In household contacts of the same children, they found an additional two cases.  WHO recommends contacts tracing in households of infectious tuberculosis patients.  Although there is still a large and important gap in the estimated number of tuberculosis cases and the number who are notified and treated by national programmes, the best ways to find the missing cases are not well established.  Even in settings where both infections are among the most important causes of mortality, tuberculosis is much less prevalent than HIV.  So the challenge for case-finding and screening approaches for tuberculosis is to select the populations most at risk. An alternative would be to develop tools that are so sensitive, specific and cheap that they can be used for widespread screening. GeneXpert® is not that tool.

While tuberculosis remains the single most important cause of mortality among people living with HIV in low resource settings, there is welcome and increasing attention being paid to human papillomaviruses (HPV).  Certain types of HPV are the cause of cervical cancer.  This is an AIDS-defining illness both because it is more common among women living with HIV and because it has such a high mortality when only detected at the late stages.  At the Paris conference there was a morning session on how to do more about cervical cancer and in particular how to build on the synergies of both HPV and HIV programmes to provide more integrated services for women who are at risk of both infections.  The most important types of HPV that cause cervical cancer can be prevented by vaccination.  However, to be most effective the vaccine has to be given prior to becoming infected with the relevant HPV strain.  So the study by Sudenga et al. in South Africa is useful as it demonstrates how many younger women aged 16-24 years in the Western Cape Province had antibodies against four of the important types included in the quadrivalent vaccine that they were testing.  The majority of participants (64%) had antibodies to two or more types present at enrolment and 12% had antibodies to all four.  Furthermore, among those participants who received placebo injections, the seroconversion rates were alarming high at 23% for HPV16 and 5% for HPV6 over the 7 months of the study among baseline seronegative participants.  South Africa has been a leader in the region in HPV vaccination for schoolgirls.  It is clear that vaccination needs to happen at a young enough age to catch most girls before they become sexually active.  This is in contrast to the offer of pre-exposure prophylaxis, which should be focused on young women who are already sexually active and at higher risk of acquiring HIV.  The specificities of synergies and integration need to be clearly delineated if we are to maximize efficiency.

HPV is also the principal cause of anal carcinoma, which is a significant problem among gay men and men who have sex with men.  Jin et al. have been building on the progress in cervical cancer screening, where new technologies such as nucleic acid detection or oncoprotein detection are leading to big improvements in some settings and replacing cytology as the first line screen for women.  The authors determined whether similar biomarkers including both nucleic acids and cellular markers could be used instead of anal cytology.  As with most advances in diagnostic technology, there is a trade-off between sensitivity and specificity.  Tests that do not miss any cases of neoplastic change are also likely to lead to many people being unnecessarily referred for further assessment and treatment.  However, both new approaches seem to be able to be calibrated in this Australian population to allow fewer referrals while still maintaining a similar sensitivity to the current cytological approach.

Acceptability of woman-delivered HIV self-testing to the male partner, and additional interventions: a qualitative study of antenatal care participants in Malawi.

Choko AT, Kumwenda MK, Johnson CC, Sakala DW, Chikalipo MC, Fielding K, Chikovore J, Desmond N, Corbett EL. J Int AIDS Soc. 2017 Jun 26;20(1):1-10. doi: 10.7448/IAS.20.1.21610.

Introduction: In the era of ambitious HIV targets, novel HIV testing models are required for hard-to-reach groups such as men, who remain underserved by existing services. Pregnancy presents a unique opportunity for partners to test for HIV, as many pregnant women will attend antenatal care (ANC). We describe the views of pregnant women and their male partners on HIV self-test kits that are woman-delivered, alone or with an additional intervention.

Methods: A formative qualitative study to inform the design of a multi-arm multi-stage cluster-randomized trial, comprised of six focus group discussions and 20 in-depth interviews, was conducted. ANC attendees were purposively sampled on the day of initial clinic visit, while men were recruited after obtaining their contact information from their female partners. Data were analysed using content analysis, and our interpretation is hypothetical as participants were not offered self-test kits.

Results: Providing HIV self-test kits to pregnant women to deliver to their male partners was highly acceptable to both women and men. Men preferred this approach compared with standard facility-based testing, as self-testing fits into their lifestyles which were characterized by extreme day-to-day economic pressures, including the need to raise money for food for their household daily. Men and women emphasized the need for careful communication before and after collection of the self-test kits in order to minimize the potential for intimate partner violence although physical violence was perceived as less likely to occur. Most men stated a preference to first self-test alone, followed by testing as a couple. Regarding interventions for optimizing linkage following self-testing, both men and women felt that a fixed financial incentive of approximately USD$2 would increase linkage. However, there were concerns that financial incentives of greater value may lead to multiple pregnancies and lack of child spacing. In this low-income setting, a lottery incentive was considered overly disappointing for those who receive nothing. Phone call reminders were preferred to short messaging service.

Conclusions: Woman-delivered HIV self-testing through ANC was acceptable to pregnant women and their male partners. Feedback on additional linkage enablers will be used to alter pre-planned trial arms.

Abstract [5] Full-text [free] access [6]

 

Effect of availability of HIV self-testing on HIV testing frequency in gay and bisexual men at high risk of infection (FORTH): a waiting-list randomised controlled trial.

Jamil MS, Prestage G, Fairley CK, Grulich AE, Smith KS, Chen M, Holt M, McNulty AM, Bavinton BR, Conway DP, Wand H, Keen P,Bradley J, Kolstee J, Batrouney C, Russell D, Law M, Kaldor JM, Guy RJ. Lancet HIV. 2017 Jun;4(6):e241-e250. doi: 10.1016/S2352-3018(17)30023-1. Epub 2017 Feb 17.

Background: Frequent testing of individuals at high risk of HIV is central to current prevention strategies. We aimed to determine if HIV self-testing would increase frequency of testing in high-risk gay and bisexual men, with a particular focus on men who delayed testing or had never been tested before.

Methods: In this randomised trial, HIV-negative high-risk gay and bisexual men who reported condomless anal intercourse or more than five male sexual partners in the past 3 months were recruited at three clinical and two community-based sites in Australia. Enrolled participants were randomly assigned (1:1) to the intervention (free HIV self-testing plus facility-based testing) or standard care (facility-based testing only). Participants completed a brief online questionnaire every 3 months, which collected the number of self-tests used and the number and location of facility-based tests, and HIV testing was subsequently sourced from clinical records. The primary outcome of number of HIV tests over 12 months was assessed overall and in two strata: recent (last test ≤2 years ago) and non-recent (>2 years ago or never tested) testers. A statistician who was masked to group allocation analysed the data; analyses included all participants who completed at least one follow-up questionnaire. After the 12 month follow-up, men in the standard care group were offered free self-testing kits for a year. This trial is registered with the Australian New Zealand clinical trials registry, number actrn12613001236785.

Findings: Between Dec 1, 2013, and Feb 5, 2015, 182 men were randomly assigned to self-testing, and 180 to standard care. The analysis population included 178 (98%) men in the self-testing group (174 person-years) and 165 (92%) in the standard care group (162 person-years). Overall, men in the self-testing group had 701 HIV tests (410 self-tests; mean 4·0 tests per year), and men in the standard care group had 313 HIV tests (mean 1·9 tests per year); rate ratio (rr) 2·08 (95% ci 1·82-2·38; p<0·0001). Among recent testers, men in the self-testing group had 627 tests (356 self-tests; mean 4·2 per year), and men in the standard care group had 297 tests (mean 2·1 per year); rr 1·99 (1·73-2·29; p<0·0001). Among non-recent testers, men in the self-testing group had 74 tests (54 self-tests; mean 2·8 per year), and men in the standard care group had 16 tests (mean 0·7 per year); rr 3·95 (2·30-6·78; p<0·0001). The mean number of facility-based HIV tests per year was similar in the self-testing and standard care groups (mean 1·7 vs 1·9 per year, respectively; rr 0·86, 0·74-1·01; P=0·074). No serious adverse events were reported during follow-up.

Interpretation: HIV self-testing resulted in a two times increase in frequency of testing in gay and bisexual men at high risk of infection, and a nearly four times increase in non-recent testers, compared with standard care, without reducing the frequency of facility-based HIV testing. HIV self-testing should be made more widely available to help increase testing and earlier diagnosis.

Abstract access [7]

 

Analysis of false-negative human immunodeficiency virus rapid tests performed on oral fluid in 3 international clinical research studies.

Curlin ME, Gvetadze R, Leelawiwat W, Martin M, Rose C, Niska RW, Segolodi TM, Choopanya K, Tongtoyai J, Holtz TH, Samandari T, McNicholl JM; OraQuick Study Group. Clin Infect Dis. 2017 Jun 15;64(12):1663-1669. doi: 10.1093/cid/cix228.

Background: The OraQuick Advance Rapid HIV-1/2 Test is a point-of-care test capable of detecting human immunodeficiency virus (HIV)-specific antibodies in blood and oral fluid. To understand test performance and factors contributing to false-negative results in longitudinal studies, we examined results of participants enrolled in the Botswana TDF/FTC Oral HIV Prophylaxis Trial, the Bangkok Tenofovir Study, and the Bangkok MSM Cohort Study, 3 separate clinical studies of high-risk, HIV-negative persons conducted in Botswana and Thailand.

Methods: In a retrospective observational analysis, we compared oral fluid OraQuick (OFOQ) results among participants becoming HIV infected to results obtained retrospectively using enzyme immunoassay and nucleic acid amplification tests on stored specimens. We categorized negative OFOQ results as true-negative or false-negative relative to nucleic acid amplification test and/or enzyme immunoassay, and determined the delay in OFOQ conversion relative to the estimated time of infection. We used log-binomial regression and generalized estimating equations to examine the association between false-negative results and participant, clinical, and testing-site factors.

Results: Two-hundred thirty-three false-negative OFOQ results occurred in 80 of 287 seroconverting individuals.  Estimated OFOQ conversion delay ranged from 14.5 to 547.5 (median, 98.5) days. Delayed OFOQ conversion was associated with clinical site and test operator (P < .05), preexposure prophylaxis (P = .01), low plasma viral load (P < .02), and time to kit expiration (P < .01). Participant age, sex, and HIV subtype were not associated with false-negative results. Long OFOQ conversion delay time was associated with antiretroviral exposure and low plasma viral load.

Conclusions: Failure of OFOQ to detect HIV-1 infection was frequent and multifactorial in origin. In longitudinal trials, negative oral fluid results should be confirmed via testing of blood samples.

Abstract access [8]

 

Multi-country validation of SAMBA - A novel molecular point-of- care test for HIV-1 detection in resource-limited setting.

Ondiek J, Namukaya Z, Mtapuri-Zinyowera S, Balkan S, Elbireer A, Ushiro Lumb I, Kiyaga C, Goel N, Ritchie A, Ncube P, Omuomu K, Ndiege K, Kekitiinwa A,Mangwanya D, Fowler MG, Nadala L, Lee H. J Acquir Immune Defic Syndr. 2017 Jun 9. doi: 10.1097/QAI.0000000000001476. [Epub ahead of print]

Introduction: Early diagnosis of HIV-1 infection and the prompt initiation of antiretroviral therapy are critical to achieving a reduction in the morbidity and mortality of infected infants. The SAMBA HIV-1 Qual Whole Blood Test was developed specifically for early infant diagnosis and prevention of mother-to-child transmission programs implemented at the point-of-care in resource-limited settings.

Methods: We have evaluated the performance of this test run on the SAMBA I semi-automated platform with fresh whole blood specimens collected from 202 adults and 745 infants in Kenya, Uganda, and Zimbabwe. Results were compared with those obtained with the Roche COBAS AmpliPrep/COBAS TaqMan (CAP/CTM) HIV-1 assay as performed with fresh whole blood or dried blood spots of the same subjects, and discrepancies were resolved with alternative assays.

Results: The performance of the SAMBA and CAP/CTM assays evaluated at five laboratories in the three countries was similar for both adult and infant samples. The clinical sensitivity, specificity, and positive and negative predictive values for the SAMBA test were 100%, 99.2%, 98.7%, and 100%, respectively, with adult samples, and 98.5%, 99.8%, 99.7%, and 98.8%, respectively, with infant samples.

Discussion: Our data suggest that the SAMBA HIV-1 Qual Whole Blood Test would be effective for early diagnosis of HIV-1 infection in infants at point-of care settings in sub-Saharan Africa.

Abstract access [9]

 

Differentiated human immunodeficiency virus RNA monitoring in resource-limited settings: an economic analysis.

Negoescu DM, Zhang Z, Bucher HC, Bendavid E; Swiss HIV Cohort Study. Clin Infect Dis. 2017 Jun 15;64(12):1724-1730. doi: 10.1093/cid/cix177.

Background: Viral load (VL) monitoring for patients receiving antiretroviral therapy (ART) is recommended worldwide. However, the costs of frequent monitoring are a barrier to implementation in resource-limited settings. The extent to which personalized monitoring frequencies may be cost-effective is unknown.

Methods: We created a simulation model parameterized using person-level longitudinal data to assess the benefits of flexible monitoring frequencies. Our data-driven model tracked human immunodeficiency virus (HIV)-infected individuals for 10 years following ART initiation. We optimized the interval between viral load tests as a function of patients' age, gender, education, duration since ART initiation, adherence behavior, and the cost-effectiveness threshold. We compared the cost-effectiveness of the personalized monitoring strategies to fixed monitoring intervals every 1, 3, 6, 12, and 24 months.

Results: Shorter fixed VL monitoring intervals yielded increasing benefits (6.034 to 6.221 discounted quality-adjusted life-years [QALYs] per patient with monitoring every 24 to 1 month over 10 years, respectively, standard error = 0.005 QALY), at increasing average costs: US$3445 (annual monitoring) to US$5393 (monthly monitoring) per patient, respectively (standard error = US$3.7). The adaptive policy optimized for low-income contexts achieved 6.142 average QALYs at a cost of US$3524, similar to the fixed 12-month policy (6.135 QALYs, US$3518). The adaptive policy optimized for middle-income resource settings yields 0.008 fewer QALYs per person, but saves US$204 compared to monitoring every 3 months.

Conclusions: The benefits from implementing adaptive vs fixed VL monitoring policies increase with the availability of resources. In low- and middle-income countries, adaptive policies achieve similar outcomes to simpler, fixed-interval policies.

Abstract [10]  Full-text [free] access [11]

 

Treatment decisions and mortality in HIV-positive presumptive smear-negative TB in the Xpert™ MTB/RIF era: a cohort study.

Hermans SM, Babirye JA, Mbabazi O, Kakooza F, Colebunders R, Castelnuovo B, Sekaggya-Wiltshire C, Parkes-Ratanshi R, Manabe YC. BMC Infect Dis. 2017 Jun 16;17(1):433. doi: 10.1186/s12879-017-2534-2.

Background: The Xpert™ MTB/RIF (XP) has a higher sensitivity than sputum smear microscopy (70% versus 35%) for TB diagnosis and has been endorsed by the WHO for TB high burden countries to increase case finding among HIV co-infected presumptive TB patients. Its impact on the diagnosis of smear-negative TB in a routine care setting is unclear. We determined the change in diagnosis, treatment and mortality of smear-negative presumptive TB with routine use of Xpert MTB/RIF (XP).

Methods: Prospective cohort study of HIV-positive smear-negative presumptive TB patients during a 12-month period after XP implementation in a well-staffed and trained integrated TB/HIV clinic in Kampala, Uganda. Prior to testing clinicians were asked to decide whether they would treat empirically prior to Xpert result; actual treatment was decided upon receipt of the XP result. We compared empirical and XP-informed treatment decisions and all-cause mortality in the first year.

Results: Of 411 smear-negative presumptive TB patients, 175 (43%) received an XP; their baseline characteristics did not differ. XP positivity was similar in patients with a pre-XP empirical diagnosis and those without (9/29 [17%] versus 14/142 [10%], P = 0.23). Despite XP testing high levels of empirical treatment prevailed (18%), although XP results did change who ultimately was treated for TB. When adjusted for CD4 count, empirical treatment was not associated with higher mortality compared to no or microbiologically confirmed treatment.

Conclusions: XP usage was lower than expected. The lower sensitivity of XP in smear-negative HIV-positive patients led experienced clinicians to use XP as a "rule-in" rather than "rule-out" test, with the majority of patients still treated empirically.

Keywords: Empirical treatment; HIV Infections/complications; Molecular diagnostic techniques/methods; Tuberculosis, pulmonary/diagnosis; Tuberculosis, pulmonary/epidemiology

Abstract [12]  Full-text [free] access  [13]

 

School and household tuberculosis contact investigations in Swaziland: Active TB case finding in a high HIV/TB burden setting.

Ustero PA, Kay AW, Ngo K, Golin R, Tsabedze B, Mzileni B,Glickman J, Wisile Xaba M, Mavimbela G, Mandalakas AM. PLoS One. 2017 Jun 5;12(6):e0178873. doi: 10.1371/journal.pone.0178873.eCollection 2017.

Background: Investigation of household contacts exposed to infectious tuberculosis (TB) is widely recommended by international guidelines to identify secondary cases of TB and limit spread. There is little data to guide the use of contact investigations outside of the household, despite strong evidence that most TB infections occur outside of the home in TB high burden settings. In older adolescents, the majority of infections are estimated to occur in school. Therefore, as part of a project to increase active case finding in Swaziland, we performed school contact investigations following the identification of a student with infectious TB.

Methods: The Butimba Project identified 7 adolescent TB index cases (age 10-20) with microbiologically confirmed disease attending 6 different schools between June 2014 and March 2015. In addition to household contact investigations, Butimba Project staff worked with the Swaziland School Health Programme (SHP) to perform school contact investigations. At 6 school TB screening events, between May and October 2015, selected students underwent voluntary TB screening and those with positive symptom screens provided sputum for TB testing.

Results: Among 2015 student contacts tested, 177 (9%) screened positive for TB symptoms, 132 (75%) produced a sputum sample, of which zero tested positive for TB. Household contact investigations of the same index cases yielded 40 contacts; 24 (60%) screened positive for symptoms; 19 produced a sputum sample, of which one case was confirmed positive for TB. The odds ratio of developing TB following household vs. school contact exposure was significantly lower (OR 0.0, 95% CI 0.0 to 0.18, P = 0.02) after exposure in school.

Conclusion: School-based contact investigations require further research to establish best practices in TB high burden settings. In this case, a symptom-based screening approach did not identify additional cases of tuberculosis. In comparison, household contact investigations yielded a higher percentage of contacts with positive TB screens and an additional tuberculosis case.

Abstract [14] Full-text [free] access [15]

 

HPV serostatus pre- and post-vaccination in a randomized phase II preparedness trial among young Western Cape, South African women: the EVRI trial.

Sudenga SL, Torres BN, Botha MH, Zeier M, Abrahamsen ME, Glashoff RH, Engelbrecht S, Schim Van der Loeff MF, Van der Laan LE, Kipping S, Taylor D, Giuliano AR. Papillomavirus Res. 2017 Jun;3:50-56. doi: 10.1016/j.pvr.2017.02.001. Epub 2017 Feb 16.

Background: HPV antibodies are a marker of past exposure to the virus. Our objective was to assess HPV serostatus pre- and post-vaccination among HIV-negative women.

Methods: Women aged 16-24 years old were randomized in a placebo controlled trial utilizing the 4-valent HPV (4vHPV) vaccine (NCT01489527, clinicaltrials.gov). Participants (n=389) received the 4vHPV vaccine or placebo following a three dose schedule. Sera were collected at Day 1 and Month 7 for assessment of HPV 6, 11, 16, and 18 neutralizing antibody levels using a multiplex competitive Luminex immunoassay (Merck) based on detecting the L1 capsid antigen for each HPV type.

Results: Seroprevalence was 73% for HPV6, 47% for HPV11, 33% for HPV16, and 44% for HPV18. Seroprevalence for any HPV type did not significantly differ by age or lifetime number of partners. The majority of participants (64%) had two or more 4vHPV antibodies present at enrollment and 12% had antibodies to all four. Among women in the vaccine arm, those that were seropositive for HPV16 at enrollment had higher titers at month 7 compared to women that were seronegative for HPV16 at enrollment; this trend holds for the other HPV types as well. Seroconversion among baseline seronegative participants in the placebo group ranged from 5% for HPV16 to 23% for HPV6.

Conclusion: HPV seroprevalence was high in this population, emphasizing the need to vaccinate prior to sexual debut.

Abstract access [16]

 

The performance of human papillomavirus biomarkers in predicting anal high-grade squamous intraepithelial lesions in gay and bisexual men.

Jin F, Roberts JM, Grulich AE, Poynten IM, Machalek DA, Cornall A, Phillips S, Ekman D, McDonald RL, Hillman RJ, Templeton DJ, Farnsworth A, Garland SM, Fairley CK, Tabrizi SN; SPANC Research Team. AIDS. 2017 Jun 1;31(9):1303-1311. doi: 10.1097/QAD.0000000000001462.

Background: We evaluate the performance of human papillomavirus (HPV) biomarkers in prediction of anal histological high-grade squamous intraepithelial lesions in gay and bisexual men (GBM) in Sydney, Australia.

Design: Baseline analysis of a 3-year cohort study.

Methods: The study of the prevention of anal cancer is natural history study of anal HPV infection in GBM aged at least 35 years. All participants completed cytological and histological assessments. Stored ThinPrep PreservCyt residua were tested for HPV genotyping (Linear Array and Cobas 4800) and viral load, E6/E7 mRNA expression (NucliSENS easyQ HPV v1) and dual cytology staining of p16/Ki 67 antibodies (CINtecPLUS). Performance of each biomarker was compared with liquid-based anal cytology. The hypothetical referral rates were defined as the proportion of men who had abnormal cytology or tested positive to each of the biomarkers.

Results: The median age of the 617 participants was 49 years (range: 35-79), and 35.7% were HIV-positive. All biomarkers were strongly associated with the grade of HPV-associated anal lesions (P < 0.001 for all). High-risk HPV (HR-HPV) viral load with a 33% cut-off and HR-HPV E6/E7 mRNA had similar sensitivity to anal cytology (78.4 and 75.4 vs. 83.2%, respectively), improved specificity (68.0 and 69.4 vs. 52.4%, respectively) and lower referral rates (47.0 and 45.0 vs. 59.2%, respectively). Specificity was significantly higher in the HIV-negative for HR-HPV viral load (72.3 vs. 58.2%, P = 0.005).

Conclusion: HR-HPV viral load and E6/E7 mRNA had similar sensitivity and higher specificity in predicting histological anal high-grade squamous intraepithelial lesion with lower referrals in GBM than anal cytology.

Abstract access  [17]

Cancers [19], Comorbidity [20], Economic modelling [21], HIV testing [22], HIV Treatment [23], Key populations [24]
Africa [25], Asia [26], Europe [27], Oceania [28]
Australia [29], Botswana [30], Kenya [31], Malawi [32], South Africa [33], Swaziland [34], Switzerland [35], Thailand [36], Uganda [37], Zimbabwe [38]
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