ABSTRACT
Introduction: HIV incidence among women in sub-Saharan Africa (SSA) has declined steadily, but it is unknown whether new infections among women who engage in sex work (WESW) have declined at a similar rate. We synthesised estimates of HIV incidence among WESW in SSA and compared these to the wider female population to understand levels and trends in incidence over time. Methods: We searched Medline, Embase, Global Health, Popline, Web of Science, and Google Scholar from January 1990 to October 2022, and grey literature for estimates of HIV incidence among WESW in SSA. We included studies reporting empirical estimates in any SSA country. We calculated incidence rate ratios (IRR) compared to age-district-year matched total female population incidence estimates. We conducted a meta-analysis of IRRs and used a continuous mixed-effects model to estimate changes in IRR over time. Results: From 32 studies between 1985 and 2020, 2,194 new HIV infections were observed in WESW over 51,000 person-years (py). Median HIV incidence was 4.3/100py (IQR 2.8-7.0/100py), declining from a median of 5.96/100py between 1985 and 1995 to a median of 3.2/100py between 2010 and 2020. Incidence among WESW was nine times higher than in matched total population women (RR 8.6, 95%CI: 5.7-12.9), and greater in Western and Central Africa (RR 22.4, 95%CI: 11.3-44.3) than in Eastern and Southern Africa (RR 5.3, 95%CI: 3.7-7.6). Annual changes in log IRRs were minimal (-0.1% 95%CI: -6.9 to +6.8%). Conclusions: Across SSA, HIV incidence among WESW remains disproportionately high compared to the total female population but showed similar rates of decline between 1990 and 2020. Improved surveillance and standardisation of approaches to obtain empirical estimates of sex worker incidence would enable a clearer understanding of whether we are on track to meet global targets for this population and better support data-driven HIV prevention programming.
ABSTRACT
BACKGROUND: The frequency of new HIV infections among female sex workers in sub-Saharan Africa is poorly understood. We used routinely collected data that enable unique identification of repeat HIV testers to assess temporal trends in seroconversion and identify associated risk factors for female sex workers accessing Sisters with a Voice, Zimbabwe's national sex worker programme. METHODS: We pooled HIV testing data gathered between Sept 15, 2009, and Dec 31, 2019, from 36 Sisters programme sites in Zimbabwe. We included female sex workers aged 16 years or older with an HIV-negative test and at least one subsequent programme test. We calculated HIV seroconversion rates (using the midpoint between the HIV-positive test and the last negative test as the seroconversion date) and estimated rate ratios to compare 2-year periods by using Poisson regression, with robust SEs to account for clustering by site and adjusting for age and testing frequency to assess temporal trends. We did sensitivity analyses to explore assumptions about seroconversion dates and the effects of variation in follow-up time on our conclusions. FINDINGS: Our analysis included data for 6665 female sex workers, 441 (7%) of whom seroconverted. The overall seroconversion rate was 3·8 (95% CI 3·4-4·2) per 100 person-years at risk. Seroconversion rates fell with time since first negative HIV test. After adjustment, there was evidence of a decrease in seroconversion rates from 2009 to 2019 (p=0·0053). In adjusted analyses, being younger than 25 years, and having a sexually transmitted infection diagnosis at a previous visit, were significantly associated with increased seroconversion rates. Our findings were mostly robust to sensitivity analyses, but when 1 month before an HIV-positive test was used as the seroconversion date, seroconversion rates no longer fell with time. INTERPRETATION: We identified high rates of seroconversion shortly after linkage to programme services, which emphasises the need to strengthen HIV prevention programmes from first contact with female sex workers in Zimbabwe. New infections among female sex workers remain challenging to measure, but longitudinal analysis of routine testing data can provide valuable insights into seroconversion rates and associated risk factors. FUNDING: UN Population Fund, Deutsche Gesellschaft für Internationale Zusammenarbeit, the Bill & Melinda Gates Foundation, The Global Fund to Fight AIDS, Tuberculosis and Malaria, US President's Emergency Plan for AIDS Relief, US Agency for International Development, and the Elton John AIDS Foundation.
Subject(s)
Acquired Immunodeficiency Syndrome , HIV Infections , HIV Seropositivity , Sex Workers , Female , Humans , HIV Infections/diagnosis , HIV Infections/epidemiology , HIV Infections/prevention & control , HIV Seropositivity/diagnosis , HIV Seropositivity/epidemiology , Retrospective Studies , Zimbabwe/epidemiology , Routinely Collected Health Data , Risk Factors , Cohort Studies , HIV TestingABSTRACT
INTRODUCTION: Early diagnosis of HIV is critical for epidemic control. To achieve this, successful testing programmes are essential and test positivity is often used as a marker of their performance. The aim of this study was to analyse trends and predictors of HIV test positivity over time and explore how an understanding of seroconversion rates could build on our interpretation of this indicator among female sex workers in Zimbabwe. METHODS: We analysed HIV test data from Zimbabwe's nationally scaled sex work programme between 2009 and 2019. We defined test positivity as the proportion of all tests that were HIV positive and measured new diagnoses by estimating seroconversion rates among women with repeat tests, defined as an HIV-positive test after at least one HIV-negative test in the programme. We used logistic regression to analyse test positivity over three time-periods: 2009-2013, 2014-2017 and 2018-2019, adjusting for potential confounding by demographic factors and the mediating effects of time since last HIV test. We calculated the seroconversion rates for the same time-periods. RESULTS: During the 10-year study period, 54,503 tests were recorded in 39,462 women. Between 2009 and 2013, 18% of tests were among women who reported testing in the previous 6 months. By 2018-2019, this had increased to 57%. Between 2018 and 2019, test positivity was 9.6%, compared to 47.9% for 2009-2013 (aOR 6.08 95% CI 5.52-6.70) and 18.8% for 2014-2017 (aOR 2.17 95% CI 2.06-2.28). Adjusting for time since last test reduced effect estimates for 2009-2013 (aOR 4.03 95% CI 3.64-4.45) and 2014-2017 (aOR 1.97 95% CI 1.86-2.09) compared to 2018-2019. Among 7573 women with an initial HIV-negative test in the programme and at least one subsequent test, 464 tested HIV positive at a rate of 3.9 per 100 pyar (95% CI 3.5-4.2). CONCLUSIONS: Test positivity decreased among women testing through the programme over time, while seroconversion rates remained high. These declines were partly driven by changes in individual testing history, reflecting comprehensive coverage of testing services and greater knowledge of HIV status, but not necessarily declining rates of seroconversion. Understanding testing history and monitoring new HIV infections from repeat tests could strengthen the interpretation of test positivity and provide a better understanding of programme performance.
Subject(s)
Epidemics , HIV Infections , Sex Workers , Female , HIV Infections/diagnosis , HIV Infections/epidemiology , Humans , Sex Work , Zimbabwe/epidemiologyABSTRACT
OBJECTIVES: Adherence to antiretroviral therapy (ART) leads to viral suppression for people living with HIV (PLHIV) and is critical for both individual health and reducing onward HIV transmission. HIV stigma is a risk factor that can undermine adherence. We explored the association between HIV stigma and self-reported ART adherence among PLHIV in 21 communities in the HPTN 071 (PopART) trial in Zambia and the Western Cape of South Africa. METHODS: We conducted a cross-sectional analysis of baseline data collected between 2013 and 2015, before the roll-out of trial interventions. Questionnaires were conducted, and consenting participants provided a blood sample for HIV testing. Poor adherence was defined as self-report of not currently taking ART, missing pills over the previous 7 days or stopping treatment in the previous 12 months. Stigma was categorised into three domains: community, health setting and internalised stigma. Multivariable logistic regression was used for analysis. RESULTS: Among 2020 PLHIV self-reporting ever taking ART, 1888 (93%) were included in multivariable analysis. Poor ART adherence was reported by 15.8% (n = 320) of participants, and 25.7% (n = 519) reported experiencing community stigma, 21.5% (n = 434) internalised stigma, and 5.7% (n = 152) health setting stigma. PLHIV who self-reported previous experiences of community and internalised stigma more commonly reported poor ART adherence than those who did not (aOR 1.63, 95% CI 1.21 -2.19, P = 0.001 and aOR 1.31, 95% CI 0.96-1.79, P = 0.09). CONCLUSIONS: HIV stigma was associated with poor ART adherence. Roll-out of universal treatment will see an increasingly high proportion of PLHIV initiated on ART. Addressing HIV stigma could make an important contribution to supporting lifelong ART adherence.
OBJECTIFS: L'adhésion à la thérapie antirétrovirale (ART) conduit à la suppression virale pour les personnes vivant avec le VIH (PVVIH) et est essentielle à la fois pour la santé individuelle et pour réduire la transmission du VIH. La stigmatisation du VIH est un facteur de risque qui peut compromettre l'adhésion. Nous avons exploré l'association entre la stigmatisation du VIH et l'adhésion autodéclarée à l'ART chez les PVVIH dans 21 communautés dans l'essai HPTN 071 (PopART) en Zambie et dans le Western Cape en Afrique du Sud. MÉTHODES: Nous avons effectué une analyse transversale des données de base collectées entre 2013-2015, avant le déploiement des interventions d'essai. Des questionnaires ont été réalisés et les participants consentants ont fourni un échantillon de sang pour le dépistage du VIH. Une mauvaise adhésion a été définie comme l'autodéclaration de ne pas prendre actuellement l'ART, d'omettre des comprimés au cours des 7 jours précédents ou d'arrêter le traitement au cours des 12 mois précédents. La stigmatisation a été classée en trois domaines: communautaire, en milieu de santé et stigmatisation intériorisée. Une régression logistique multivariée a été utilisée pour l'analyse. RÉSULTATS: Parmi les 2.020 PVVIH autodéclarant avoir déjà pris un ART, 1.888 (93%) ont été inclus dans l'analyse multivariée. Une mauvaise adhésion à l'ART a été signalée par 15,8% (n = 320) des participants, 25,7% (n = 519) ont déclaré avoir subi une stigmatisation communautaire, 21,5% (n = 434) une stigmatisation internalisée et 5,7% (n = 152) une stigmatisation en milieu de santé. Les PVVIH qui ont auto-déclaré des expériences antérieures de stigmatisation communautaire et intériorisée ont plus souvent rapporté une mauvaise adhésion à l'ART que ceux qui ne l'ont pas fait (aOR 1,63 ; IC95%: 1,21-2,19 ; P = 0,001 et aOR 1,31 ; IC95%: 0,96-1,79 ; P = 0,09). CONCLUSIONS: La stigmatisation du VIH était associée à une mauvaise adhésion à l'ART. Le déploiement du traitement universel verra une proportion de plus en plus élevée de PVVIH initiées à l'ART. Lutter contre la stigmatisation du VIH pourrait apporter une contribution importante au soutien de l'adhésion à l'ART au cours de la vie. NUMÉRO D'ESSAI CLINIQUE: NCT01900977.
