Organisation of testing services, structural barriers and facilitators of routine HIV self-testing during sexually transmitted infection consultations: a qualitative study of patients and providers in Abidjan, Côte d'Ivoire.

BACKGROUND: Consultations for sexually transmitted infection (STI) provide an opportunity to offer HIV testing to both patients and their partners. This study describes the organisation of HIV self-testing (HIVST) distribution during STI consultations in Abidjan (Côte d'Ivoire) and analyse the perceived barriers and facilitators associated with the use and redistribution of HIVST kits by STI patients. MATERIALS AND METHODS: A qualitative study was conducted between March and August 2021 to investigate three services providing HIVST: an antenatal care clinic (ANC), a general health centre that also provided STI consultations, and a dedicated STI clinic. Data were collected through observations of medical consultations with STI patients (N = 98) and interviews with both health professionals involved in HIVST distribution (N = 18) and STI patients who received HIVST kits for their partners (N = 20). RESULTS: In the ANC clinic, HIV testing was routinely offered during the first prenatal visit. HIVST was commonly offered to women who had been diagnosed with an STI for their partner's use (27/29 observations). In the general health centre, two parallel pathways coexisted: before the consultation, a risk assessment tool was used to offer HIV testing to eligible patients and, after the consultation, patients who had been diagnosed with an STI were referred to a care assistant for HIVST. Due to this HIV testing patient flow, few offers of HIV testing and HIVST were made in this setting (3/16). At the dedicated STI clinic, an HIVST video was played in the waiting room. According to the health professionals interviewed, this video helped reduce the time required to offer HIVST after the consultation. Task-shifting was implemented there: patients were referred to a nurse for HIV testing, and HIVST was commonly offered to STI patients for their partners' use (28/53). When an HIVST was offered, it was generally accepted (54/58). Both health professionals and patients perceived HIVST positively despite experiencing a few difficulties with respect to offering HIVST to partners and structural barriers associated with the organisation of services. CONCLUSION: The organisation of patient flow and task-shifting influenced HIV testing and offers of HIVST kits. Proposing HIVST is more systematic when HIV testing is routinely offered to all patients. Successful integration requires improving the organisation of services, including task-shifting.

The Association Between Heterosexual anal Intercourse and HIV Acquisition in Three Prospective Cohorts of Women.

The extent to which receptive anal intercourse (RAI) increases the HIV acquisition risk of women compared to receptive vaginal intercourse (RVI) is poorly understood. We evaluated RAI practice over time and its association with HIV incidence during three prospective HIV cohorts of women: RV217, MTN-003 (VOICE), and HVTN 907. At baseline, 16% (RV 217), 18% (VOICE) of women reported RAI in the past 3 months and 27% (HVTN 907) in the past 6 months, with RAI declining during follow-up by around 3-fold. HIV incidence in the three cohorts was positively associated with reporting RAI at baseline, albeit not always significantly. The adjusted hazard rate ratios for potential confounders (aHR) were 1.1 (95% Confidence interval: 0.8-1.5) for VOICE and 3.3 (1.6-6.8) for RV 217, whereas the ratio of cumulative HIV incidence by RAI practice was 1.9 (0.6-6.0) for HVTN 907. For VOICE, the estimated magnitude of association increased slightly when using a time-varying RAI exposure definition (aHR = 1.2; 0.9-1.6), and for women reporting RAI at every follow-up survey (aHR = 2.0 (1.3-3.1)), though not for women reporting higher RAI frequency (> 30% acts being RAI vs. no RAI in the past 3 months; aHR = 0.7 (0.4-1.1)). Findings indicated precise estimation of the RAI/HIV association, following multiple RVI/RAI exposures, is sensitive to RAI exposure definition, which remain imperfectly measured. Information on RAI practices, RAI/RVI frequency, and condom use should be more systematically and precisely recorded and reported in studies looking at sexual behaviors and HIV seroconversions; standardized measures would aid comparability across geographies and over time.

Can HIV self-testing reach first-time testers? A telephone survey among self-test end users in Côte d'Ivoire, Mali, and Senegal.

BACKGROUND: Coverage of HIV testing remains sub-optimal in West Africa. Between 2019 and 2022, the ATLAS program distributed ~400 000 oral HIV self-tests (HIVST) in Côte d'Ivoire, Mali, and Senegal, prioritising female sex workers (FSW) and men having sex with men (MSM), and relying on secondary redistribution of HIVST to partners, peers and clients to reach individuals not tested through conventional testing. This study assesses the proportion of first-time testers among HIVST users and the associated factors. METHODS: A phone-based survey was implemented among HIVST users recruited using dedicated leaflets inviting them to anonymously call a free phone number. We collected socio-demographics, sexual behaviours, HIV testing history, HIVST use, and satisfaction with HIVST. We reported the proportion of first-time testers and computed associated factors using logistic regression. RESULTS: Between March and June 2021, 2 615 participants were recruited for 50 940 distributed HIVST (participation rate: 5.1%). Among participants, 30% received their HIVST kit through secondary distribution (from a friend, sexual partner, family member, or colleague). The proportion who had never tested for HIV before HIVST (first-time testers) was 41%. The main factors associated with being a first-time tester were sex, age group, education level, condom use, and secondary distribution. A higher proportion was observed among those aged 24 years or less (55% vs 32% for 25-34, aOR: 0.37 [95%CI: 0.30-0.44], and 26% for 35 years or more, aOR: 0.28 [0.21-0.37]); those less educated (48% for none/primary education vs 45% for secondary education, aOR: 0.60 [0.47-0.77], and 29% for higher education, aOR: 0.33 [0.25-0.44]). A lower proportion was observed among women (37% vs 43%, aOR: 0.49 [0.40-0.60]); those reporting always using a condom over the last year (36% vs 51% for those reporting never using them, aOR: 2.02 [1.59-2.56]); and those who received their HISVST kit through primary distribution (39% vs 46% for secondary distribution, aOR: 1.32 [1.08-1.60]). CONCLUSION: ATLAS HIVST strategy, including secondary distribution, successfully reached a significant proportion of first-time testers. HIVST has the potential to reach underserved populations and contribute to the expansion of HIV testing services in West Africa.

Describing, analysing and understanding the effects of the introduction of HIV self-testing in West Africa through the ATLAS programme in Côte d'Ivoire, Mali and Senegal.

BACKGROUND: The ATLAS programme aims to promote and implement HIV self-testing (HIVST) in three West African countries: Côte d'Ivoire, Mali, and Senegal. During 2019-2021, in close collaboration with the national AIDS implementing partners and communities, ATLAS plans to distribute 500,000 HIVST kits through eight delivery channels, combining facility-based, community-based strategies, primary and secondary distribution of HIVST. Considering the characteristics of West African HIV epidemics, the targets of the ATLAS programme are hard-to-reach populations: key populations (female sex workers, men who have sex with men, and drug users), their clients or sexual partners, partners of people living with HIV and patients diagnosed with sexually transmitted infections and their partners. The ATLAS programme includes research support implementation to generate evidence for HIVST scale-up in West Africa. The main objective is to describe, analyse and understand the social, health, epidemiological effects and cost-effectiveness of HIVST introduction in Côte d'Ivoire, Mali and Senegal to improve the overall HIV testing strategy (accessibility, efficacy, ethics). METHODS: ATLAS research is organised into five multidisciplinary workpackages (WPs): Key Populations WP: qualitative surveys (individual in-depth interviews, focus group discussions) conducted with key actors, key populations, and HIVST users. Index testing WP: ethnographic observation of three HIV care services introducing HIVST for partner testing. Coupons survey WP: an anonymous telephone survey of HIVST users. Cost study WP: incremental economic cost analysis of each delivery model using a top-down costing with programmatic data, complemented by a bottom-up costing of a representative sample of HIVST distribution sites, and a time-motion study for health professionals providing HIVST. Modelling WP: Adaptation, parameterisation and calibration of a dynamic compartmental model that considers the varied populations targeted by the ATLAS programme and the different testing modalities and strategies. DISCUSSION: ATLAS is the first comprehensive study on HIV self-testing in West Africa. The ATLAS programme focuses particularly on the secondary distribution of HIVST. This protocol was approved by three national ethic committees and the WHO's Ethical Research Committee.

Increases in HIV Incidence Following Receptive Anal Intercourse Among Women: A Systematic Review and Meta-analysis.

Receptive anal intercourse (RAI) carries a greater per-act risk of HIV acquisition than receptive vaginal intercourse (RVI) and may influence HIV epidemics driven by heterosexual sex. This systematic review explores the association between RAI and incident HIV among women, globally. We searched Embase and Medline through September 2018 for longitudinal studies reporting crude (cRR) or adjusted (aRR) relative risks of HIV acquisition by RAI practice among women. Of 27,563 articles identified, 17 eligible studies were included. We pooled independent study estimates using random-effects models. Women reporting RAI were more likely to acquire HIV than women not reporting RAI (pooled cRR = 1.56 95% CI 1.03-2.38, N = 18, I2 = 72%; pooled aRR = 2.23, 1.01-4.92, N = 5, I2 = 70%). In subgroup analyses the association was lower for women in Africa (pooled cRR = 1.16, N = 13, I2 = 21%) than outside Africa (pooled cRR = 4.10, N = 5, I2 = 79%) and for high-risk (pooled aRR = 1.69, N = 4, I2 = 63%) than general-risk women (pooled aRR = 8.50, N = 1). Interview method slightly influenced cRR estimates (p value = 0.04). In leave-one-out sensitivity analyses pooled estimates were generally robust to removing individual study estimates. Main limitations included poor exposure definition, incomplete adjustment for confounders, particularly condom use, and use of non-confidential interview methods. More and better data are needed to explain differences in risk by world region and risk population. Women require better counselling and greater choice in prevention modalities that are effective during RVI and RAI.

What Proportion of Female Sex Workers Practise anal Intercourse and How Frequently? A Systematic Review and Meta-analysis.

HIV is more efficiently acquired during receptive anal intercourse (AI) compared to vaginal intercourse (VI) and may contribute substantially to female sex workers' (FSW) high HIV burden. We aim to determine how common and frequent AI is among FSW globally. We searched PubMed, Embase and PsycINFO for studies reporting the proportion of FSW practising AI (prevalence) and/or the number of AI acts (frequency) worldwide from 01/1980 to 10/2018. We assessed the influence of participant and study characteristics on AI prevalence (e.g. continent, study year and interview method) through sub-group analysis. Of 15,830 identified studies, 131 were included. Nearly all (N = 128) reported AI prevalence and few frequency (N = 13), over various recall periods. Most studies used face-to-face interviews (N = 111). Pooled prevalences varied little by recall period (lifetime: 15.7% 95%CI 12.2-19.3%, N = 30, I2 = 99%; past month: 16.2% 95%CI 10.8-21.6%, N = 18, I2 = 99%). The pooled proportion of FSW reporting < 100% condom use tended to be non-significantly higher during AI compared to during VI (e.g. any unprotected VI: 19.1% 95%CI 1.7-36.4, N = 5 and any unprotected AI: 46.4% 95%CI 9.1-83.6, N = 5 in the past week). Across all study participants, between 2.4 and 15.9% (N = 6) of all intercourse acts (AI and VI) were anal. Neither AI prevalence nor frequency varied substantially by any participant or study characteristics. Although varied, AI among FSW is generally common, inconsistently protected with condoms and practiced sufficiently frequently to contribute substantially to HIV acquisition in this risk group. Interventions to address barriers to condom use are needed.

Detailed contact data and the dissemination of Staphylococcus aureus in hospitals.

Close proximity interactions (CPIs) measured by wireless electronic devices are increasingly used in epidemiological models. However, no evidence supports that electronically collected CPIs inform on the contacts leading to transmission. Here, we analyzed Staphylococcus aureus carriage and CPIs recorded simultaneously in a long-term care facility for 4 months in 329 patients and 261 healthcare workers to test this hypothesis. In the broad diversity of isolated S. aureus strains, 173 transmission events were observed between participants. The joint analysis of carriage and CPIs showed that CPI paths linking incident cases to other individuals carrying the same strain (i.e. possible infectors) had fewer intermediaries than predicted by chance (P < 0.001), a feature that simulations showed to be the signature of transmission along CPIs. Additional analyses revealed a higher dissemination risk between patients via healthcare workers than via other patients. In conclusion, S. aureus transmission was consistent with contacts defined by electronically collected CPIs, illustrating their potential as a tool to control hospital-acquired infections and help direct surveillance.

New HIV Infections Among Key Populations and Their Partners in 2010 and 2022, by World Region: A Multisources Estimation.

BACKGROUND: Previously, The Joint United Nations Programme on HIV/AIDS estimated proportions of adult new HIV infections among key populations (KPs) in the last calendar year, globally and in 8 regions. We refined and updated these, for 2010 and 2022, using country-level trend models informed by national data. METHODS: Infections among 15-49 year olds were estimated for sex workers (SWs), male clients of female SW, men who have sex with men (MSM), people who inject drugs (PWID), transgender women (TGW), and non-KP sex partners of these groups. Transmission models used were Goals (71 countries), AIDS Epidemic Model (13 Asian countries), Optima (9 European and Central Asian countries), and Thembisa (South Africa). Statistical Estimation and Projection Package fits were used for 15 countries. For 40 countries, new infections in 1 or more KPs were approximated from first-time diagnoses by the mode of transmission. Infection proportions among nonclient partners came from Goals, Optima, AIDS Epidemic Model, and Thembisa. For remaining countries and groups not represented in models, median proportions by KP were extrapolated from countries modeled within the same region. RESULTS: Across 172 countries, estimated proportions of new adult infections in 2010 and 2022 were both 7.7% for SW, 11% and 20% for MSM, 0.72% and 1.1% for TGW, 6.8% and 8.0% for PWID, 12% and 10% for clients, and 5.3% and 8.2% for nonclient partners. In sub-Saharan Africa, proportions of new HIV infections decreased among SW, clients, and non-KP partners but increased for PWID; elsewhere these groups' 2010-to-2022 differences were opposite. For MSM and TGW, the proportions increased across all regions. CONCLUSIONS: KPs continue to have disproportionately high HIV incidence.

Cost-effectiveness analysis of community-led HIV self-testing among key populations in Côte d'Ivoire, Mali, and Senegal.

INTRODUCTION: HIV self-testing (HIVST) is a promising strategy to improve diagnosis coverage among key populations (KP). The ATLAS (Auto Test VIH, Libre d'Accéder à la connaissance de son Statut) programme implemented HIVST in three West African countries, distributing over 380,000 kits up between 2019 and 2021, focussing on community-led distribution by KP to their peers and subsequent secondary distribution to their partners and clients. We aim to evaluate the cost-effectiveness of community-led HIVST in Côte d'Ivoire, Mali and Senegal. METHODS: An HIV transmission dynamics model was adapted and calibrated to country-specific epidemiological data and used to predict the impact of HIVST. We considered the distribution of HIVST among two KP-female sex workers (FSW), and men who have sex with men (MSM)-and their sexual partners and clients. We compared the cost-effectiveness of two scenarios against a counterfactual without HIVST over a 20-year horizon (2019-2039). The ATLAS-only scenario mimicked the 2-year implemented ATLAS programme, whereas the ATLAS-scale-up scenario achieved 95% coverage of HIVST distribution among FSW and MSM by 2025 onwards. The primary outcome is the number of disability-adjusted life-years (DALY) averted. Scenarios were compared using incremental cost-effectiveness ratios (ICERs). Costing was performed using a healthcare provider's perspective. Costs were discounted at 4%, converted to $USD 2022 and estimated using a cost-function to accommodate economies of scale. RESULTS: The ATLAS-only scenario was highly cost-effective over 20 years, even at low willingness-to-pay thresholds. The median ICERs were $126 ($88-$210) per DALY averted in Côte d'Ivoire, $92 ($88-$210) in Mali and 27$ ($88-$210) in Senegal. Scaling-up the ATLAS programme would also be cost-effective, and substantial epidemiological impacts would be achieved. The ICERs for the scale-up scenario were $199 ($122-$338) per DALY averted in Côte d'Ivoire, $224 ($118-$415) in Mali and $61 ($18-$128) in Senegal. CONCLUSIONS: Both the implemented and the potential scale-up of community-led HIVST programmes in West Africa, where KP are important to overall transmission dynamics, have the potential to be highly cost-effective, as compared to a scenario without HIVST. These findings support the scale-up of community-led HIVST to reach populations that otherwise may not access conventional testing services.

The impact of past HIV interventions and diagnosis gaps on new HIV acquisitions, transmissions, and HIV-related deaths in Côte d'Ivoire, Mali, and Senegal.

OBJECTIVES: To estimate the epidemiological impact of past HIV interventions and the magnitude and contribution of undiagnosed HIV among different risk groups on new HIV acquisitions in Côte d'Ivoire, Mali and Senegal. DESIGN: HIV transmission dynamic models among the overall population and key populations [female sex workers (FSW), their clients, and MSM]. METHODS: Models were independently parameterized and calibrated for each set of country-specific demographic, behavioural, and epidemiological data. We estimated the fraction of new HIV infections over 2012-2021 averted by condom use and antiretroviral therapy (ART) uptake among key population and nonkey population, the direct and indirect contribution of specific groups to new infections [transmission population-attributable fraction (tPAF)] over 2012-2021 due to prevention gaps, and the distribution of undiagnosed PWH by risk group in January 2022 and their tPAF over 2022-2031. RESULTS: Condom use and ART may have averted 81-88% of new HIV infections over 2012-2021 across countries, mostly because of condom use by key population. The tPAF of all key populations combined over 2012-2021 varied between 27% (Côte d'Ivoire) and 79% (Senegal). Male key population (clients of FSW and MSM) contributed most to new infections (>60% in Mali and Senegal) owing to their higher HIV prevalence and larger prevention gaps. In 2022, men represented 56% of all PWH with an undiagnosed infection in Côte d'Ivoire (male key population = 15%), 46% in Mali (male key population = 23%), and 69% in Senegal (male key population = 55%). If HIV testing and ART initiation rates remain at current levels, 20% of new HIV infections could be due to undiagnosed key population PWH in Côte d'Ivoire over 2022-2031, 53% in Mali, and 65% in Senegal. CONCLUSION: Substantial HIV diagnosis gaps remain in Western Africa, especially among male key population. Addressing these gaps is key to impacting the HIV epidemics in the region and achieving the goal of ending AIDS by 2030.

Potential population-level effects of HIV self-test distribution among key populations in Côte d'Ivoire, Mali, and Senegal: a mathematical modelling analysis.

BACKGROUND: During 2019-21, the AutoTest VIH, Libre d'accéder à la connaissance de son Statut (ATLAS) programme distributed around 380 000 HIV self-testing kits to key populations, including female sex workers, men who have sex with men, and their partners, in Côte d'Ivoire, Mali, and Senegal. We aimed to estimate the effects of the ATLAS programme and national scale-up of HIV self-test distribution on HIV diagnosis, HIV treatment coverage, HIV incidence, and HIV-related mortality. METHODS: We adapted a deterministic compartmental model of HIV transmission in Côte d'Ivoire, parameterised and fitted to country-specific demographic, behavioural, HIV epidemiological, and intervention data in Côte d'Ivoire, Mali, and Senegal separately during 1980-2020. We simulated dynamics of new HIV infections, HIV diagnoses, and HIV-related deaths within scenarios with and without HIV self-test distribution among key populations. Models were separately parameterised and fitted to country-specific sets of epidemiological and intervention outcomes (stratified by sex, risk, age group, and HIV status, if available) over time within a Bayesian framework. We estimated the effects on the absolute increase in the proportion of people with HIV diagnosed at the end of 2021 for the ATLAS-only scenario and at the end of 2028 and 2038 for the HIV self-testing scale-up scenario. We estimated cumulative numbers of additional HIV diagnoses and initiations of antiretroviral therapy and the proportion and absolute numbers of new HIV infections and HIV-related deaths averted during 2019-21 and 2019-28 for the ATLAS-only scenario and during 2019-28 and 2019-38 for the HIV self-testing scale-up scenario. FINDINGS: Our model estimated that ATLAS could have led to 700 (90% uncertainty interval [UI] 500-900) additional HIV diagnoses in Côte d'Ivoire, 500 (300-900) in Mali, and 300 (50-700) in Senegal during 2019-21, a 0·4 percentage point (90% UI 0·3-0·5) increase overall by the end of 2021. During 2019-28, ATLAS was estimated to avert 1900 (90% UI 1300-2700) new HIV infections and 600 (400-800) HIV-related deaths across the three countries, of which 38·6% (90% UI 31·8-48·3) of new infections and 70·1% (60·4-77·3) of HIV-related deaths would be among key populations. ATLAS would avert 1·5% (0·8-3·1) of all HIV-related deaths across the three countries during this period. Scaling up HIV self-testing would avert 16·2% (90% UI 10·0-23·1) of all new HIV infections during 2019-28 in Senegal, 5·3% (3·0-8·9) in Mali, and 1·6% (1·0-2·4) in Côte d'Ivoire. HIV self-testing scale-up among key populations was estimated to increase HIV diagnosis by the end of 2028 to 1·3 percentage points (90% UI 0·8-1·9) in Côte d'Ivoire, 10·6 percentage points (5·3-16·8) in Senegal, and 3·6 percentage points (2·0-6·4) in Mali. INTERPRETATION: Scaling up HIV self-test distribution among key populations in western Africa could attenuate disparities in access to HIV testing and reduce infections and deaths among key populations and their partners. FUNDING: Unitaid, Solthis, the UK Medical Research Council Centre for Global Infectious Disease Analysis, the EU European & Developing Countries Clinical Trials Partnership programme, and the Wellcome Trust. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Comparison of Empirically Derived and Model-Based Estimates of Key Population HIV Incidence and the Distribution of New Infections by Population Group in Sub-Saharan Africa.

BACKGROUND: The distribution of new HIV infections among key populations, including female sex workers (FSWs), gay men and other men who have sex with men (MSM), and people who inject drugs (PWID) are essential information to guide an HIV response, but data are limited in sub-Saharan Africa (SSA). We analyzed empirically derived and mathematical model-based estimates of HIV incidence among key populations and compared with the Joint United Nations Programme on HIV/AIDS (UNAIDS) estimates. METHODS: We estimated HIV incidence among FSW and MSM in SSA by combining meta-analyses of empirical key population HIV incidence relative to the total population incidence with key population size estimates (KPSE) and HIV prevalence. Dynamic HIV transmission model estimates of HIV incidence and percentage of new infections among key populations were extracted from 94 country applications of 9 mathematical models. We compared these with UNAIDS-reported distribution of new infections, implied key population HIV incidence and incidence-to-prevalence ratios. RESULTS: Across SSA, empirical FSW HIV incidence was 8.6-fold (95% confidence interval: 5.7 to 12.9) higher than total population female 15-39 year incidence, and MSM HIV incidence was 41.8-fold (95% confidence interval: 21.9 to 79.6) male 15-29 year incidence. Combined with KPSE, these implied 12% of new HIV infections in 2021 were among FSW and MSM (5% and 7% respectively). In sensitivity analysis varying KPSE proportions within 95% uncertainty range, the proportion of new infections among FSW and MSM was between 9% and 19%. Insufficient data were available to estimate PWID incidence rate ratios. Across 94 models, median proportion of new infections among FSW, MSM, and PWID was 6.4% (interquartile range 3.2%-11.7%), both much lower than the 25% reported by UNAIDS. CONCLUSION: Empirically derived and model-based estimates of HIV incidence confirm dramatically higher HIV risk among key populations in SSA. Estimated proportions of new infections among key populations in 2021 were sensitive to population size assumptions and were substantially lower than estimates reported by UNAIDS.

Measuring HIV Acquisitions Among Partners of Key Populations: Estimates From HIV Transmission Dynamic Models.

BACKGROUND: Key populations (KPs), including female sex workers (FSWs), gay men and other men who have sex with men (MSM), people who inject drugs (PWID), and transgender women (TGW) experience disproportionate risks of HIV acquisition. The UNAIDS Global AIDS 2022 Update reported that one-quarter of all new HIV infections occurred among their non-KP sexual partners. However, this fraction relied on heuristics regarding the ratio of new infections that KPs transmitted to their non-KP partners to the new infections acquired among KPs (herein referred to as "infection ratios"). We recalculated these ratios using dynamic transmission models. SETTING: One hundred seventy-eight settings (106 countries). METHODS: Infection ratios for FSW, MSM, PWID, TGW, and clients of FSW were estimated from 12 models for 2020. RESULTS: Median model estimates of infection ratios were 0.7 (interquartile range: 0.5-1.0; n = 172 estimates) and 1.2 (0.8-1.8; n = 127) for acquisitions from FSW clients and transmissions from FSW to all their non-KP partners, respectively, which were comparable with the previous UNAIDS assumptions (0.2-1.5 across regions). Model estimates for female partners of MSM were 0.5 (0.2-0.8; n = 20) and 0.3 (0.2-0.4; n = 10) for partners of PWID across settings in Eastern and Southern Africa, lower than the corresponding UNAIDS assumptions (0.9 and 0.8, respectively). The few available model estimates for TGW were higher [5.1 (1.2-7.0; n = 8)] than the UNAIDS assumptions (0.1-0.3). Model estimates for non-FSW partners of FSW clients in Western and Central Africa were high (1.7; 1.0-2.3; n = 29). CONCLUSIONS: Ratios of new infections among non-KP partners relative to KP were high, confirming the importance of better addressing prevention and treatment needs among KP as central to reducing overall HIV incidence.

The population impact of herpes simplex virus type 2 (HSV-2) vaccination on the incidence of HSV-2, HIV and genital ulcer disease in South Africa: a mathematical modelling study.

BACKGROUND: Evidence suggests HSV-2 infection increases HIV acquisition risk and HIV/HSV-2 coinfection increases transmission risk of both infections. We analysed the potential impact of HSV-2 vaccination in South Africa, a high HIV/HSV-2 prevalence setting. METHODS: We adapted a dynamic HIV transmission model for South Africa to incorporate HSV-2, including synergistic effects with HIV, to evaluate the impact of: (i) cohort vaccination of 9-year-olds with a prophylactic vaccine that reduces HSV-2 susceptibility; (ii) vaccination of symptomatically HSV-2-infected individuals with a therapeutic vaccine that reduces HSV shedding. FINDINGS: An 80% efficacious prophylactic vaccine offering lifetime protection with 80% uptake could reduce HSV-2 and HIV incidence by 84.1% (95% Credibility Interval: 81.2-86.0) and 65.4% (56.5-71.6) after 40 years, respectively. This reduces to 57.4% (53.6-60.7) and 42.1% (34.1-48.1) if efficacy is 50%, 56.1% (53.4-58.3) and 41.5% (34.2-46.9) if uptake is 40%, and 29.4% (26.0-31.9) and 24.4% (19.0-28.7) if protection lasts 10 years. An 80% efficacious therapeutic vaccine offering lifetime protection with 40% coverage among symptomatic individuals could reduce HSV-2 and HIV incidence by 29.6% (21.8-40.9) and 26.4% (18.5-23.2) after 40 years, respectively. This reduces to 18.8% (13.7-26.4) and 16.9% (11.7-25.3) if efficacy is 50%, 9.7% (7.0-14.0) and 8.6% (5.8-13.4) if coverage is 20%, and 5.4% (3.8-8.0) and 5.5% (3.7-8.6) if protection lasts 2 years. INTERPRETATION: Prophylactic and therapeutic vaccines offer promising approaches for reducing HSV-2 burden and could have important impact on HIV in South Africa and other high prevalence settings. FUNDING: WHO, NIAID.

Modelling the effects of population structure on childhood disease: the case of varicella.

Realistic, individual-based models based on detailed census data are increasingly used to study disease transmission. Whether the rich structure of such models improves predictions is debated. This is studied here for the spread of varicella, a childhood disease, in a realistic population of children where infection occurs in the household, at school, or in the community at large. A methodology is first presented for simulating households with births and aging. Transmission probabilities were fitted for schools and community, which reproduced the overall cumulative incidence of varicella over the age range of 0-11 years old.Moreover, the individual-based model structure allowed us to reproduce several observed features of VZV epidemiology which were not included as hypotheses in the model: the age at varicella in first-born children was older than in other children, in accordance with observation; the same was true for children residing in rural areas. Model predicted incidence was comparable to observed incidence over time. These results show that models based on detailed census data on a small scale provide valid small scale prediction. By simulating several scenarios, we evaluate how varicella epidemiology is shaped by policies, such as age at first school enrolment, and school eviction. This supports the use of such models for investigating outcomes of public health measures.

Routine programmatic data show a positive population-level impact of HIV self-testing: the case of Côte d'Ivoire and implications for implementation.

OBJECTIVES: We estimate the effects of ATLAS's HIV self-testing (HIVST) kit distribution on conventional HIV testing, diagnoses, and antiretroviral treatment (ART) initiations in Côte d'Ivoire. DESIGN: Ecological study using routinely collected HIV testing services program data. METHODS: We used the ATLAS's programmatic data recorded between the third quarter of 2019 and the first quarter of 2021, in addition to data from the President's Emergency Plan for AIDS Relief dashboard. We performed ecological time series regression using linear mixed models. Results are presented per 1000 HIVST kits distributed through ATLAS. RESULTS: We found a negative but nonsignificant effect of the number of ATLAS' distributed HIVST kits on conventional testing uptake (-190 conventional tests; 95% confidence interval [CI]: -427 to 37). The relationship between the number of HIVST kits and HIV diagnoses was significant and positive (+8 diagnosis; 95% CI: 0 to 15). No effect was observed on ART initiation (-2 ART initiations; 95% CI: -8 to 5). CONCLUSIONS: ATLAS' HIVST kit distribution had a positive impact on HIV diagnoses. Despite the negative signal on conventional testing, even if only 20% of distributed kits are used, HIVST would increase access to testing. The methodology used in this paper offers a promising way to leverage routinely collected programmatic data to estimate the effects of HIVST kit distribution in real-world programs.

Estimating the effect of HIV on cervical cancer elimination in South Africa: Comparative modelling of the impact of vaccination and screening.

Background: In 2020, the World Health Organization (WHO) launched its initiative to eliminate cervical cancer as a public health problem. To inform global efforts for countries with high HIV and cervical cancer burden, we assessed the impact of human papillomavirus (HPV) vaccination and cervical cancer screening and treatment in South Africa, on cervical cancer and the potential for achieving elimination before 2120, considering faster HPV disease progression and higher cervical cancer risk among women living with HIV(WLHIV) and HIV interventions. Methods: Three independent transmission-dynamic models simulating HIV and HPV infections and disease progression were used to predict the impact on cervical cancer incidence of three scenarios for all women: 1) girls' vaccination (9-14 years old), 2) girls' vaccination plus 1 lifetime cervical screen (at 35 years), and 3) girls' vaccination plus 2 lifetime cervical screens (at 35 and 45 years) and three enhanced scenarios for WLHIV: 4) vaccination of young WLHIV aged 15-24 years, 5) three-yearly cervical screening of WLHIV aged 15-49 years, or 6) both. Vaccination assumed 90% coverage and 100% lifetime protection with the nonavalent vaccine (against HPV-16/18/31/33/45/52/58). Cervical cancer screening assumed HPV testing with uptake increasing from 45% (2023), 70% (2030) to 90% (2045+). We also assumed that UNAIDS 90-90-90 HIV treatment and 70% male circumcision targets are reached by 2030. We examined three elimination thresholds: age-standardised cervical cancer incidence rates below 4 or 10 per 100,000 women-years, and >85% reduction in cervical cancer incidence rate. We conducted sensitivity analyses and presented the median age-standardised predictions of outcomes of the three models (minimum-maximum across models). Findings: Girls' vaccination could reduce age-standardised cervical cancer incidence from a median of 47.6 (40.9-79.2) in 2020 to 4.5 (3.2-6.3) per 100,000 women-years by 2120, averting on average ∼4% and ∼46% of age-standardised cumulative cervical cancer cases over 25 and 100 years, respectively, compared to the basecase. Adding 2 lifetime screens helped achieve elimination over the century among all women (2120 cervical cancer incidence: 3.6 (1.9-3.6) per 100,000 women-years), but not among WLHIV (10.8 (5.3-11.6)), and averted more cumulative cancer cases overall (∼45% over 25 years and ∼61% over 100 years compared to basecase) than girls' vaccination alone. Adding three-yearly cervical screening among WLHIV (to girls' vaccination and 2 lifetime cervical screens) further reduced age-standardised cervical cancer incidence to 3.3 (1.8-3.6) per 100,000 women-years overall and to 5.2 (3.9-8.5) among WLHIV by 2120 and averted on average 12-13% additional cumulative cancer cases among all women and 21-24% among WLHIV than girls' vaccination and 2 lifetime cervical screens over 25 years or longer. Long-term vaccine protection and using the nonavalent vaccine was required for elimination. Interpretation: High HPV vaccination coverage of girls and 2 lifetime cervical screens could eliminate cervical cancer among women overall in South Africa by the end of the century and substantially decrease cases among all women and WLHIV over the short and medium term. Cervical cancer elimination in WLHIV would likely require enhanced prevention strategies for WLHIV. Screening of WLHIV remains an important strategy to reduce incidence and alleviate disparities in cervical cancer burden between women with and without HIV, despite HIV interventions scale-up. Funding: World Health Organization. National Cancer Institute, National Institutes of Health. MRC Centre for Global Infectious Disease Analysis, UK Medical Research Council. National Institute of Child Health and Human Development research. Cancer Association of South Africa. Canadian Institutes of Health Research and the Fonds de recherche du Québec - Santé research.

Willingness to use and distribute HIV self-test kits to clients and partners: A qualitative analysis of female sex workers' collective opinion and attitude in Côte d'Ivoire, Mali, and Senegal.

BACKGROUND: In West Africa, female sex workers are at increased risk of HIV acquisition and transmission. HIV self-testing could be an effective tool to improve access to and frequency of HIV testing to female sex workers, their clients and partners. This article explores their perceptions regarding HIV self-testing use and the redistribution of HIV self-testing kits to their partners and clients. METHODS: Embedded within ATLAS, a qualitative study was conducted in Côte-d'Ivoire, Mali, and Senegal in 2020. Nine focus group discussions were conducted. A thematic analysis was performed. RESULTS: A total of 87 participants expressed both positive attitudes toward HIV self-testing and their willingness to use or reuse HIV self-testing. HIV self-testing was perceived to be discreet, confidential, and convenient. HIV self-testing provides autonomy from testing by providers and reduces stigma. Some perceived HIV self-testing as a valuable tool for testing their clients who are willing to offer a premium for condomless sex. While highlighting some potential issues, overall, female sex workers were optimistic about linkage to confirmatory testing following a reactive HIV self-testing. Female sex workers expressed positive attitudes toward secondary distribution to their partners and clients, although it depended on relationship types. They seemed more enthusiastic about secondary distribution to their regular/emotional partners and regular clients with whom they had difficulty using condoms, and whom they knew enough to discuss HIV self-testing. However, they expressed that it could be more difficult with casual clients; the duration of the interaction being too short to discuss HIV self-testing, and they fear violence and/or losing them. CONCLUSION: Overall, female sex workers have positive attitudes toward HIV self-testing use and are willing to redistribute to their regular partners and clients. However, they are reluctant to promote such use with their casual clients. HIV self-testing can improve access to HIV testing for female sex workers and the members of their sexual and social network.

Estimating the epidemic consequences of HIV prevention gaps among key populations.

INTRODUCTION: HIV epidemic appraisals are used to characterize heterogeneity and inequities in the context of the HIV pandemic and the response. However, classic measures used in appraisals have been shown to underestimate disproportionate risks of onward transmission, particularly among key populations. In response, a growing number of modelling studies have quantified the consequences of unmet prevention and treatment needs (prevention gaps) among key populations as a transmission population attributable fraction over time (tPAFt ). To aid its interpretation and use by programme implementers and policy makers, we outline and discuss a conceptual framework for understanding and estimating the tPAFt via transmission modelling as a measure of onward transmission risk from HIV prevention gaps; and discuss properties of the tPAFt . DISCUSSION: The distribution of onward transmission risks may be defined by who is at disproportionate risk of onward transmission, and under which conditions. The latter reflects prevention gaps, including secondary prevention via treatment: the epidemic consequences of which may be quantified by the tPAFt . Steps to estimating the tPAFt include parameterizing the acquisition and onward transmission risks experienced by the subgroup of interest, defining the most relevant counterfactual scenario, and articulating the time-horizon of analyses and population among whom to estimate the relative difference in cumulative transmissions; such steps could reflect programme-relevant questions about onward transmission risks. Key properties of the tPAFt include larger onward transmission risks over longer time-horizons; seemingly mutually exclusive tPAFt measures summing to greater than 100%; an opportunity to quantify the magnitude of disproportionate onward transmission risks with a per-capita tPAFt ; and that estimates are conditional on what has been achieved so far in reducing prevention gaps and maintaining those conditions moving forward as the status quo. CONCLUSIONS: The next generation of HIV epidemic appraisals has the potential to support a more specific HIV response by characterizing heterogeneity in disproportionate risks of onward transmission which are defined and conditioned on the past, current and future prevention gaps across subsets of the population.