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Background: Effective strategies to reduce sexually transmitted infection burden and transmission among female sex workers (FSWs) and their networks are needed. We report sexually transmitted infection prevalence among FSWs in Zimbabwe and investigate the performance of screening algorithms., Methods: Respondent-driven sampling (RDS) surveys, including blood sampling for syphilis serology, were conducted among FSWs in 3 communities in Zimbabwe in 2017. In addition, a random sample of one-third of participants were offered genital examination and sexually transmitted infection (STI) testing. Data on symptoms and clinical signs were analyzed to determine the proportion of asymptomatic and clinically inapparent STIs by HIV status, and the sensitivity, specificity, and predictive values of syndromic, clinical, and hybrid screening algorithms for chlamydia and gonorrhea. Analyses were RDS-II weighted., Results: Overall, 2507 women were included in the RDS surveys, and 661 of 836 (79.1%) of those randomly offered genital examination and STI testing accepted. The prevalence of STI by site ranged from 15.7% to 20.0% for syphilis (rapid plasma reagin + Treponema pallidum hemagglutination assay), 6.8% to 14.3% for gonorrhea, 8.4% to 10.1% for chlamydia, 26.6% to 35.5% for trichomonas, and 37.0% to 47.6% for any high-risk human papilloma virus. A high proportion of infections were both asymptomatic and clinically undetectable (gonorrhea: 41.2%, chlamydia: 51.7%, trichomonas: 62.8%). Screening algorithms performed poorly whether based on symptoms only (sensitivity: 53.3% gonorrhea, 43.3% chlamydia) or either symptoms or clinical signs (sensitivity: 58.7% gonorrhea, 48.3% chlamydia)., Conclusions: Sexually transmitted infection burden is high among FSWs in Zimbabwe. The low sensitivity and specificity of screening algorithms used to guide syndromic management mean that more effective approaches are required to strengthen STI control. As access to HIV-specific prevention methods like preexposure prophylaxis increases, support for consistent condom use needs to be strengthened., Competing Interests: Conflict of Interest and Sources of Funding: This research was funded in whole or in part by the President's Emergency Plan for AIDS Relief (PEPFAR) through the Centers for Disease Control and Prevention (CDC) under the terms of grant no. 1U2GPS003118-05-03 between CDC and RTI to support the implementation of the Building Health Data Dissemination and Information Use Systems in the Republic of Zimbabwe under the President's Emergency Place for AIDS Relief Activities, and by the Wellcome Trust (grant no. 214280/Z/18/Z). The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Sexually Transmitted Diseases Association.)

Background: HIV prevalence and incidence has declined in East, Central, and Southern Africa (ECSA), but remains high among female sex workers (FSWs). Sex worker programmes have the potential to considerably increase access to HIV testing, prevention, and treatment. We aimed to quantify these improvements by modelling the potential effect of sex worker programmes at two different intensities on HIV incidence and key health outcomes, and assessed the programmes' potential cost-effectiveness in order to help inform HIV policy decisions., Methods: Using a model previously used to review policy decisions in ECSA, we assumed a low-intensity sex worker programme had run from 2010 until 2023; this resulted in care disadvantages among FSWs being reduced, and also increased testing, condom use, and willingness to take pre-exposure prophylaxis (PrEP). After 2023, three policy options were considered: discontinuation, continuation, and a scale-up of the programme to high-intensity, which would have a broader reach, and higher influences on condom use, antiretroviral therapy (ART) adherence, testing, and PrEP use. Outputs of the key outcomes (the percentage of FSWs who were diagnosed with HIV, on ART, and virally suppressed; the percentage of FSWs with zero condomless partners, and HIV incidence) were compared in 2030. The maximum cost for a sex worker programme to be cost-effective was calculated over a 50-year time period and in the context of 10 million adults. The cost-effectiveness analysis was conducted from a health-care perspective; costs and disability-adjusted life-years were both discounted to present US$ values at 3% per annum., Findings: Compared with continuing a low-intensity sex worker programme until 2030, discontinuation of the programme was calculated to result in a lower percentage of FSWs diagnosed (median 88·75% vs 91·37%; median difference compared to continuation of a low-intensity programme [90% range] 2·03 [-4·49 to 10·98]), a lower percentage of those diagnosed currently taking ART (86·35% vs 88·89%; 2·38 [-3·69 to 13·42]), and a lower percentage of FSWs on ART with viral suppression (87·49% vs 88·96%; 1·17 [-6·81 to 11·53]). Discontinuation of a low-intensity programme also resulted in an increase in HIV incidence among FSWs from 5·06 per 100 person-years (100 p-y; 90% range 0·52 to 22·21) to 4·05 per 100 p-y (0·21 to 21·15). Conversely, comparing a high-intensity sex worker programme until 2030 with discontinuation of the programme resulted in a higher percentage of FSWs diagnosed (median 95·81% vs 88·75; median difference compared to discontinuation [90% range] 6·36 [0·60 to 18·63]), on ART (93·93 vs 86.35%; median difference 7·13 [-0·65 to 26·48]), and with viral suppression (93·21% vs 87·49; median difference 7·13 [-0·65 to 26·48]). A high-intensity programme also resulted in HIV incidence in FSWs declining to 2·23 per 100 p-y (0·00 to 14·44), from 5·06 per 100 p-y (0·52 to 22·21) if the programme was discontinued. In the context of 10 million adults over a 50-year time period and a cost-effectiveness threshold of US$500 per disability-adjusted life-year averted, $34 million per year can be spent for a high-intensity programme to be cost-effective., Interpretation: A sex worker programme, even with low-level interventions, has a positive effect on key outputs for FSWs. A high-intensity programme has a considerably higher effect; HIV incidence among FSW and in the general population can be substantially reduced, and should be considered for implementation by policy makers., Funding: Wellcome Trust., Competing Interests: Declaration of interests LB-M and ANP have received funds paid to their institution from the Wellcome Trust for this study (grant number: 214280/Z/18/Z), the Bill & Melinda Gates Foundation, and Horizon Europe (grant number 101103140). FMC and JRH have received funds paid to their institution from the Wellcome Trust for this study. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Female sex workers remain disproportionately affected by HIV. The aim of this study was to determine the effect of risk-differentiated, peer-led support for female sex workers in Zimbabwe on the risk of HIV acquisition and HIV transmission from sex among female sex workers., Methods: In this cluster randomised, open-label, controlled study, 22 clinics dedicated to female sex workers co-located in government health facilities throughout Zimbabwe were allocated (1:1, through restricted randomisation) to usual care or AMETHIST intervention. Usual care comprised HIV testing, pre-exposure prophylaxis (PrEP), referral to government antiretroviral therapy (ART) services, contraception, condoms, syndromic management of sexually transmitted infections, health education, legal advice, and peer support. AMETHIST added peer-led microplanning tailored to individuals' risk and participatory self-help groups. All cisgender women (aged >18 years) who had sold sex within the past 30 days and lived or worked within trial cluster areas were eligible. Intervention status was not masked to programme implementers but was masked to survey teams and laboratory staff. After 28 months, a respondent-driven sampling (RDS) survey was done in the female sex worker population around each clinic, which measured the primary outcome, the combined proportion of female sex workers in the surveyed population at risk of transmitting HIV (ie, were HIV positive, not virally suppressed, and not consistently using condoms) or at risk of acquiring HIV (ie, were HIV negative and not consistently using condoms or PrEP). We report prespecified analyses of the disaggregated proportions of female sex workers in the surveyed population at risk of either transmission or acquisition of HIV. Analyses were prespecified, RDS-weighted, and age-adjusted. This trial is registered with the Pan African Clinical Trials Registry, PACTR202007818077777., Findings: The AMETHIST intervention was started on May 15, 2019, and data were collected from June 1, 2019, until Dec 13, 2021. The RDS survey was done from Oct 18 to Dec 13, 2021, with 2137 women included in the usual care group (11 clusters) and 2131 in the AMETHIST intervention group (11 clusters) after excluding survey seeds (n=132) and women with missing key data (n=44). 1973 (46·2%) of the 4268 female sex workers surveyed were living with HIV; of these, 863 (93·5%; RDS-adjusted) of 931 women in the intervention group and 927 (88·8%) of 1042 in the usual care group were virologically suppressed. 287 (22·4%) of 1200 HIV-negative women in the intervention group and 194 (15·7%) of 1096 in the usual care group reported currently taking PrEP, of whom only two (0·4%) of 569 had protective tenofovir diphosphate concentrations in dried blood spots (>700 fmol/dried blood punch). There was no effect of the intervention on the primary endpoint of risk of both HIV transmission and acquisition (intervention group n=1156/2131, RDS-adjusted proportion 55·3%; usual care group n=1104/2137, RDS-adjusted proportion 52·7%; age-adjusted risk difference -0·9%, 95% CI -5·7% to 3·9%, p=0·70). For the secondary outcomes, the proportion of women living with HIV at risk of transmission was low and significantly reduced in the intervention group (n=63/931, RDS-adjusted proportion 5·8%) compared with the usual care group (103/1041, 10·4%), with an age-adjusted risk difference of -5·5% (95% CI -8·2% to -2·9%, p=0·0003). Risk of acquisition among HIV-negative women was similar in the intervention (n=1093/1200, RDS-adjusted proportion 92·1%) and the usual care group (1001/1096, 92·2%), with an age-adjusted risk difference of -0·6% (95% CI -4·6 to 3·4, p=0·74)., Interpretation: There was no overall benefit of the intervention on combined risk of transmission or acquisition. Viral load suppression in women living with HIV was high and appeared to be further improved by AMETHIST, suggesting potential for impressive uptake and adherence to ART in vulnerable and mobile populations. Sustaining treatment and reinvigorating prevention remain crucial., Funding: The Wellcome Trust and the Bill & Melinda Gates Foundation., Translations: For the Shona and Ndebele translations of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Introduction: We used a Programme Science platform, to generate evidence to support the implementation of programmes for sex workers in Africa. Female sex workers are estimated to make up 1.6% (1.3%-1.8%) of the population of women aged 15-49 years in Zimbabwe. We highlight how programme science can be used to help distinguish between when, where and with whom programmes need to be implemented and discuss two case studies that exemplify implementing better (Case study 1 (1 June 2019-30 June 2021) Optimizing implementation of a risk differentiated microplanning intervention) and implementing differently (Case study 2 (1 October 2016-30 September 2022) Reorientating implementation of DREAMS for young women selling sex)., Methods: Zimbabwe's nationally scaled programme for sex workers was established in 2009 in partnership with sex workers to provide comprehensive services for sex workers and generate evidence for programme design, implementation and scale up. Since inception, comprehensive data have been collected from all sex workers seeking services. As the scope of service provision has expanded so has the scope of data collection and analysis. At enrolment, sex workers are assigned an alphanumeric unique identifier which links consultations within and across programme sites. We conduct descriptive analyses of the Key Population (KP) programme data to guide programme implementation and redesign, embedding programmatic qualitative enquiry as required., Results: Two case studies describing different approaches to programme optimization are presented. In the first, an optimization exercise was used to strengthen programme implementation ensuring that the KP programme got back on track after SARS-COV-2. In the second, an in-depth review of research and programme data led to a re-orientation of the DREAMS programme to ensure that young women at the highest risk of HIV acquisition were enrolled and had access to DREAMS social support interventions in turn strengthening their uptake of HIV prevention., Conclusions: Optimizing and sustaining HIV care and treatment programmes requires effective delivery with sufficient scale and intensity for population impact. Our programme science approach guided the scale up of the KP programme in Zimbabwe, providing evidence to support strategy, implementation and ongoing management, and importantly helping us distinguish between when we needed to just implement, implement better or implement differently., (© 2024 The Author(s). Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of International AIDS Society.)

Background: Syndromic management is widely used to treat symptomatic sexually transmitted infections in settings without aetiologic diagnostics. However, underlying aetiologies and consequent treatment suitability are uncertain without regular assessment. This systematic review estimated the distribution, trends, and determinants of aetiologies for vaginal discharge, urethral discharge, and genital ulcer in sub-Saharan Africa (SSA)., Methods and Findings: We searched Embase, MEDLINE, Global Health, Web of Science, and grey literature from inception until December 20, 2023, for observational studies reporting aetiologic diagnoses among symptomatic populations in SSA. We adjusted observations for diagnostic test performance, used generalised linear mixed-effects meta-regressions to generate estimates, and critically appraised studies using an adapted Joanna Briggs Institute checklist. Of 4,418 identified records, 206 reports were included from 190 studies in 32 countries conducted between 1969 and 2022. In 2015, estimated primary aetiologies for vaginal discharge were candidiasis (69.4% [95% confidence interval (CI): 44.3% to 86.6%], n = 50), bacterial vaginosis (50.0% [95% CI: 32.3% to 67.8%], n = 39), chlamydia (16.2% [95% CI: 8.6% to 28.5%], n = 50), and trichomoniasis (12.9% [95% CI: 7.7% to 20.7%], n = 80); for urethral discharge were gonorrhoea (77.1% [95% CI: 68.1% to 84.1%], n = 68) and chlamydia (21.9% [95% CI: 15.4% to 30.3%], n = 48); and for genital ulcer were herpes simplex virus type 2 (HSV-2) (48.3% [95% CI: 32.9% to 64.1%], n = 47) and syphilis (9.3% [95% CI: 6.4% to 13.4%], n = 117). Temporal variation was substantial, particularly for genital ulcer where HSV-2 replaced chancroid as the primary cause. Aetiologic distributions for each symptom were largely the same across regions and population strata, despite HIV status and age being significantly associated with several infection diagnoses. Limitations of the review include the absence of studies in 16 of 48 SSA countries, substantial heterogeneity in study observations, and impeded assessment of this variability due to incomplete or inconsistent reporting across studies., Conclusions: In our study, syndrome aetiologies in SSA aligned with World Health Organization guidelines without strong evidence of geographic or demographic variation, supporting broad guideline applicability. Temporal changes underscore the importance of regular aetiologic re-assessment for effective syndromic management., Prospero Number: CRD42022348045., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Michalow et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: There is a paucity of evidence on HIV vulnerabilities and service engagements among people who sell sex in sub-Saharan Africa and identify as cisgender men, transgender women, or transgender men. We aimed to describe sexual risk behaviours, HIV prevalence, and access to HIV services among cisgender men, transgender women, and transgender men who sell sex in Zimbabwe., Methods: We did a cross-sectional analysis of routine programme data that were collected between July 1, 2018, and June 30, 2020, from cisgender men who sell sex, transgender women who sell sex, and transgender men who sell sex, as part of accessing sexual and reproductive health and HIV services provided through the Sisters with a Voice programme, at 31 sites across Zimbabwe. All people who sell sex reached by the programme had routine data collected, including routine HIV testing, and were referred using a network of peer educators. Sexual risk behaviours, HIV prevalence, and HIV services uptake during the period from July, 2018, to June, 2020, were analysed through descriptive statistics by gender group., Findings: A total of 1003 people who sell sex were included in our analysis: 423 (42·2%) cisgender men, 343 (34·2%) transgender women, and 237 (23·6%) transgender men. Age-standardised HIV prevalence estimates were 26·2% (95% CI 22·0-30·7) among cisgender men, 39·4% (34·1-44·9) among transgender women, and 38·4% (32·1-45·0) among transgender men. Among people living with HIV, 66·0% (95% CI 55·7-75·3) of cisgender men, 74·8% (65·8-82·4) of transgender women, and 70·2% (59·3-79·7) of transgender men knew their HIV status, and 15·5% (8·9-24·2), 15·7% (9·5-23·6), and 11·9% (5·9-20·8) were on antiretroviral therapy, respectively. Self-reported condom use was consistently low across gender groups, ranging from 26% (95% CI 22-32) for anal sex among transgender women to 32% (27-37) for vaginal sex among cisgender men., Interpretation: These unique data show that people who sell sex and identify as cisgender men, transgender women, or transgender men in sub-Saharan Africa have high HIV prevalences and risk of infection, with alarmingly low access to HIV prevention, testing, and treatment services. There is an urgent need for people-centred HIV interventions for these high-risk groups and for more inclusive HIV policies and research to ensure we truly attain universal access for all., Funding: Aidsfonds Netherlands., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

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., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Objectives: Sex work sites have been hypothesised to be at the root of the observed heterogeneity in HIV prevalence in sub-Saharan Africa. We determined if proximity to sex work sites is associated with HIV prevalence among the general population in Zimbabwe, a country with one of the highest HIV prevalence in the world., Methods: In this cross-sectional study we use a unique combination of nationally representative geolocated individual-level data from 16,121 adults (age 15-49 years) from 400 sample locations and the locations of 55 sex work sites throughout Zimbabwe; covering an estimated 95% of all female sex workers (FSWs). We calculated the shortest distance by road from each survey sample location to the nearest sex work site, for all sites and by type of sex work site, and conducted univariate and multivariate multilevel logistic regressions to determine the association between distance to sex work sites and HIV seropositivity, controlling for age, sex, male circumcision status, number of lifetime sex partners, being a FSW client or being a stable partner of an FSW client., Results: We found no significant association between HIV seroprevalence and proximity to the nearest sex work site among the general population in Zimbabwe, regardless of which type of site is closest (city site adjusted odds ratio [aOR] 1.010 [95% confidence interval {CI} 0.992-1.028]; economic growth point site aOR 0.982 [95% CI 0.962-1.002]; international site aOR 0.995 [95% CI 0.979-1.012]; seasonal site aOR 0.987 [95% CI 0.968-1.006] and transport site aOR 1.007 [95% CI 0.987-1.028]). Individual-level indicators of sex work were significantly associated with HIV seropositivity: being an FSW client (aOR 1.445 [95% CI 1.188-1.745]); nine or more partners versus having one to three lifetime partners (aOR 2.072 [95% CI 1.654-2.596])., Conclusions: Sex work sites do not seem to directly affect HIV prevalence among the general population in surrounding areas. Prevention and control interventions for HIV at these locations should primarily focus on sex workers and their clients, with special emphasis on including and retaining mobile sex workers and clients into services., (© 2022 The Authors Tropical Medicine & International Health Published by John Wiley & Sons Ltd.)

Background: Young women who sell sex (YWSS), are underserved by available HIV prevention and care services. The Determined, Resilient, Empowered, AIDS-free, Mentored and Safe (DREAMS) Partnership aimed to reduce the risk of HIV acquisition among vulnerable populations of adolescent girls and young women, including YWSS, in 10 sub-Saharan African countries. We describe 2 methods, respondent-driven sampling (RDS) and peer outreach, used to refer YWSS for DREAMS services in Zimbabwe, and compare the characteristics and engagement of YWSS referred to these services by each method. We hypothesized that RDS would identify YWSS at higher risk of HIV and those who were less engaged with HIV prevention and care services than peer outreach., Objective: We aimed to compare respondent-driven sampling and peer outreach in recruiting and referring high-risk populations for HIV prevention and care services., Methods: We used RDS, a sampling method designed to reach a representative sample of the network of key populations, and peer outreach, a programmatic approach to identify, reach, and refer YWSS for DREAMS between April and July 2017, and January 2017 and July 2018, respectively, in 2 cities in Zimbabwe. For RDS, we conducted detailed mapping to understand sex work typology and geography, and then purposively selected 10 "seed" participants in each city to initiate RDS. For peer outreach, we initiated recruitment through 18 trained and age-matched peer educators using youth-tailored community mobilization. We described the characteristics and service engagement of YWSS who accessed DREAMS services by each referral approach and assessed the association of these characteristics with referral approach using the chi-square test. Analysis was performed with and without restricting the period when RDS took place. We estimated the relative incremental costs of recruiting YWSS using each strategy for referral to DREAMS services., Results: Overall, 5386 and 1204 YWSS were referred for DREAMS services through peer outreach and RDS, respectively. YWSS referred through RDS were more likely to access DREAMS services compared to YWSS referred through peer outreach (501/1204, 41.6% vs 930/5386, 17.3%; P<.001). Regardless of referral approach, YWSS who accessed DREAMS had similar education levels, and a similar proportion tested HIV negative and reported not using a condom at the last sex act. A higher proportion of YWSS accessing DREAMS through RDS were aged 18-19 years (167/501, 33.3% vs 243/930, 26.1%; P=.004) and more likely to be aware of their HIV status (395/501, 78.8% vs 396/930, 42.6%; P<.001) compared to those accessing DREAMS services through peer outreach. The incremental cost per young woman who sells sex recruited was US $7.46 for peer outreach and US $52.81 for RDS., Conclusions: Peer outreach and RDS approaches can reach and refer high-risk but different groups of YWSS for HIV services, and using both approaches will likely improve reach., International Registered Report Identifier (irrid): RR2-DOI 10.1186/s12889-018-5085-6., (©Sungai T Chabata, Rumbidzo Makandwa, Bernadette Hensen, Phillis Mushati, Tarisai Chiyaka, Sithembile Musemburi, Joanna Busza, Sian Floyd, Isolde Birdthistle, James R Hargreaves, Frances M Cowan. Originally published in JMIR Public Health and Surveillance (https://publichealth.jmir.org), 27.07.2022.)

Objectives: To estimate HIV incidence among female sex workers (FSW) in Zimbabwe: using HIV prevalence by age and number of years since started selling sex (YSSS)., Design: We pooled data from FSW aged 18-39 participating in respondent-driven sampling surveys conducted in Zimbabwe between 2011 and 2017., Methods: For each year of age, we estimated: HIV prevalence ( Pt ) and the change in HIV prevalence from the previous age ( Pt - Pt -1 ). We then estimated the rate of new HIV infections during that year of age: It  =  Pt - Pt -1 /(1 - Pt -1 ), and calculated HIV incidence for 18-24 and 25-39 year-olds separately as the weighted average of It . We estimated HIV incidence for FSW 1-5 years and 6-15 years since first selling sex using the same approach, and compared HIV prevalence among FSW first selling sex at their current age with the general population., Results: Among 9906 women, 50.2% were HIV positive. Based on HIV prevalence increases by age, we estimated an HIV incidence of 6.3/100 person-years at risk (pyar) (95% confidence interval [CI] 5.3, 7.6) among 18-24 year-olds, and 3.3/100 pyar (95% CI 1.3, 4.2) among 25-39 year-olds. Based on prevalence increases by YSSS, HIV incidence was 5.3/100 pyar (95% CI 4.3, 8.5) between 1 and 5 years since first selling sex, and 2.1/100 pyar (95% CI -1.3, 7.2) between 6 and 15 years., Conclusions: Our analysis is consistent with very high HIV incidence among FSW in Zimbabwe, especially among those who are young and recently started selling sex. There is a critical need to engage young entrants into sex work in interventions that reduce their HIV risk., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

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., (© 2022 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Introduction: Young female sex workers (FSW) are disproportionately vulnerable to HIV. Zimbabwe data show higher HIV incidence and lower engagement in services compared to older FSW. Utilizing data from a combination HIV prevention and treatment intervention, we describe engagement in the HIV services over time among FSW 18-24 years, compared to those ≥25 years of age., Materials and Methods: Data were collected via respondent-driven sampling (RDS) surveys in 14 communities in 2013 and 2016, with >2500 FSW per survey. They included blood samples for HIV and viral load testing. As the intervention had no significant impact on HIV care cascade outcomes, data were aggregated across study arms. Analyses used RDS-II estimation., Results: Mean age in 2013 and 2016 was 31 and 33 years, with 27% and 17% aged 18-24 years. Overall HIV prevalence was 59% at each timepoint, and 35% and 36% among younger FSW. From 2013 to 2016 there was an increase in young HIV-positive FSW knowing their status (38% vs 60%, OR = 2.51, p<0.01). Outcomes for all FSW improved significantly over time at all steps of the cascade, and the relative change over time was similar among older versus younger FSW for most cascade variables., Discussion: Young FSW had improvements in care cascade outcomes, and proportionate improvements similar to older FSW, yet they remain less engaged in services overall. This implies that the dedicated FSW services in Zimbabwe are having a comparably positive impact across age groups, however more is likely required to address young FSW's unique vulnerabilities and needs., Competing Interests: The authors have declared that no competing interests exist.

Background: Female sex workers (FSW) in sub-Saharan Africa are disproportionately affected by HIV and are critical to engage in HIV prevention, testing and care services. We describe the design of our evaluation of the 'AMETHIST' intervention, nested within a nationally-scaled programme for FSW in Zimbabwe. We hypothesise that the implementation of this intervention will result in a reduction in the risk of HIV transmission within sex work., Methods: The AMETHIST intervention (Adapted Microplanning to Eliminate Transmission of HIV in Sex Transactions) is a risk-differentiated intervention for FSW, centred around the implementation of microplanning and self-help groups. It is designed to support uptake of, and adherence to, HIV prevention, testing and treatment behaviours among FSW. Twenty-two towns in Zimbabwe were randomised to receive either the Sisters programme (usual care) or the Sisters programme plus AMETHIST. The composite primary outcome is defined as the proportion of all FSW who are at risk of either HIV acquisition (HIV-negative and not fully protected by prevention interventions) or of HIV transmission (HIV-positive, not virally suppressed and not practicing consistent condom use). The outcome will be assessed after 2 years of intervention delivery in a respondent-driven sampling survey (total n = 4400; n = 200 FSW recruited at each site). Primary analysis will use the 'RDS-II' method to estimate cluster summaries and will adapt Hayes and Moulton's '2-step' method produce adjusted effect estimates. An in-depth process evaluation guided by our project trajectory will be undertaken., Discussion: Innovative pragmatic trials are needed to generate evidence on effectiveness of combination interventions in HIV prevention and treatment in different contexts. We describe the design and analysis of such a study., Trial Registration: Pan African Clinical Trials Registry PACTR202007818077777 . Registered on 2 July 2020., (© 2022. The Author(s).)

Female sex workers' livelihoods in Zimbabwe have been severely impacted by the coronavirus disease 2019 pandemic due to closure of entertainment venues. Competition over fewer clients has reduced ability to negotiate condom use. At the same time as partner numbers have decreased, frequency of reported condomless sex has not increased, suggesting potential reduction in overall HIV and sexually transmitted infection risk and an opportunity for programmes to reach sex workers with holistic social and economic support and prevention services., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Introduction: Reaching men aged 20-35 years, the group at greatest risk of HIV, with voluntary medical male circumcision (VMMC) remains a challenge. We assessed the impact of two VMMC demand creation approaches targeting this age group in a randomised controlled trial (RCT)., Methods: We conducted a 2×2 factorial RCT comparing arms with and without two interventions: (1) standard demand creation augmented by human-centred design (HCD)-informed approach; (2) standard demand creation plus offer of HIV self-testing (HIVST). Interpersonal communication (IPC) agents were the unit of randomisation. We observed implementation of demand creation over 6 months (1 May to 31 October 2018), with number of men circumcised assessed over 7 months. The primary outcome was the number of men circumcised per IPC agent using the as-treated population of actual number of months each IPC agent worked. We conducted a mixed-methods process evaluation within the RCT., Results: We randomised 140 IPC agents, 35 in each arm. 132/140 (94.3%) attended study training and 105/132 (79.5%) reached at least one client during the trial period and were included in final analysis. There was no evidence that the HCD-informed intervention increased VMMC uptake versus no HCD-informed intervention (incident rate ratio (IRR) 0.87, 95% CI 0.38 to 2.02; p=0.75). Nor did offering men a HIVST kit at time of VMMC mobilisation (IRR 0.65, 95% CI 0.28 to 1.50; p=0.31). Among IPC agents that reported reaching at least one man with demand creation, both the HCD-informed intervention and HIVST were deemed useful. There were some challenges with trial implementation; <50% of IPC agents converted any men to VMMC, which undermined our ability to show an effect of demand creation and may reflect acceptability and feasibility of the interventions., Conclusion: This RCT did not show evidence of an effect of HCD-informed demand intervention or HIVST on VMMC uptake. Findings will inform future design and implementation of demand creation evaluations., Trial Registration Number: PACTR201804003064160., Competing Interests: Competing interests: None declared., (©World Health Organization 2021. Licensee BMJ.)

Introduction: Young women who sell sex (YWSS) are at disproportionate risk of HIV. Reducing YWSS' vulnerability requires engaging their male sexual partners. To achieve this, we need to understand the characteristics and dynamics of their sexual partnerships to inform effective interventions., Methods: We conducted a mixed-methods study to compare YWSS' qualitative descriptions of male partners with categories reported in a behavioral survey. Data were drawn from enrollment into an evaluation of the DREAMS initiative in Zimbabwe in 2017. As part of a respondent-driven sampling survey, we recruited 40 seed participants from 2 intervention and 4 comparison sites. We conducted semistructured interviews with 19 "seeds," followed by a behavioral survey with 2387 YWSS. We interpreted quantitative and qualitative data together to understand how YWSS perceived male sexual partners, assess how well survey variables related to narrative descriptions, and describe patterns of risk behavior within partnerships., Results: Qualitative data suggest survey categories "husband" and "client" reflect YWSS' perceptions but "regular partner/boyfriend" and "casual partner" do not. In interviews, use of the term "boyfriend" was common, describing diverse relationships with mixed emotional and financial benefits. More than 85% of male partners provided money to YWSS, but women were less likely to report condomless sex with clients than regular partners (11% vs 37%) and more likely to report condomless sex with partners who ever forced them to have sex (37% vs 21%)., Conclusions: Reducing HIV risk among YWSS requires prevention messages and tools that recognize diverse and changing vulnerability within and between sexual relationships with different male partners., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Introduction: Young women who sell sex (YWSS) in Zimbabwe remain at high risk of HIV infection. Effective HIV prevention strategies are needed. Through support to access a combination of evidence-based interventions, including oral pre-exposure prophylaxis (PrEP), the Determined, Resilient, Empowered, AIDS-free, Mentored and Safe (DREAMS) partnership aimed to reduce new HIV infections among adolescent girls and young women by 40% over 24 months., Methods: Non-randomised 'plausibility' evaluation, powered to detect a 40% HIV incidence difference between DREAMS and non-DREAMS sites. Two large cities with DREAMS funding were included, and four smaller non-DREAMS towns for comparison. In all sites, YWSS were enrolled to a cohort through peer-referral. Women were followed up for 24 months. HIV seroconversion was the primary outcome, with secondary outcomes identified through a theory of change. Outcomes were compared between YWSS recruited in DREAMS cities and non-DREAMS towns, adjusting for individual-level confounders and HIV prevalence at enrolment., Results: From April to July 2017, 2431 women were enrolled, 1859 of whom were HIV negative at enrolment; 1019 of these women (54.8%) were followed up from March to May 2019 and included in endline analysis. Access to clinical services increased, but access to socioeconomic interventions promoted by DREAMS was limited. A total of 79 YWSS HIV seroconverted, with HIV incidence among YWSS in DREAMS cities lower (3.1/100 person-years) than in non-DREAMS towns (5.3/100 person-years). In prespecified adjusted analysis, HIV incidence was lower in DREAMS cities but with weak statistical evidence (adjusted rate ratio (RR)=0.68; 95% CI 0.40 to 1.19; p=0.18). Women in DREAMS cities were more likely to report ever and ongoing PrEP use, consistent condom use, fewer sexual partners and less intimate partner violence., Conclusion: It is plausible that DREAMS lowered HIV incidence among YWSS in two Zimbabwean cities, but our evaluation provides weak statistical evidence for impact and suggests any reduction in incidence was lower than the anticipated 40% decline. We identified changes to some important 'pathways to impact' variables, including condom use., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: National-level population size estimates (PSEs) for hidden populations are required for HIV programming and modelling. Various estimation methods are available at the site-level, but it remains unclear which are optimal and how best to obtain national-level estimates., Setting: Zimbabwe., Methods: Using 2015-2017 data from respondent-driven sampling (RDS) surveys among female sex workers (FSW) aged 18+ years, mappings, and program records, we calculated PSEs for each of the 20 sites across Zimbabwe, using up to 3 methods per site (service and unique object multipliers, census, and capture-recapture). We compared estimates from different methods, and calculated site medians. We estimated prevalence of sex work at each site using census data available on the number of 15-49-year-old women, generated a list of all "hotspot" sites for sex work nationally, and matched sites into strata in which the prevalence of sex work from sites with PSEs was applied to those without. Directly and indirectly estimated PSEs for all hotspot sites were summed to provide a national-level PSE, incorporating an adjustment accounting for sex work outside hotspots., Results: Median site PSEs ranged from 12,863 in Harare to 247 in a rural growth-point. Multiplier methods produced the highest PSEs. We identified 55 hotspots estimated to include 95% of all FSW. FSW nationally were estimated to number 40,491, 1.23% of women aged 15-49 years, (plausibility bounds 28,177-58,797, 0.86-1.79%, those under 18 considered sexually exploited minors)., Conclusion: There are large numbers of FSW estimated in Zimbabwe. Uncertainty in population size estimation should be reflected in policy-making.

Background: Population size estimates (PSEs) for hidden populations at increased risk of HIV, including female sex workers (FSWs), are important to inform public health policy and resource allocation. The service multiplier method (SMM) is commonly used to estimate the sizes of hidden populations. We used this method to obtain PSEs for FSWs at 9 sites in Zimbabwe and explored methods for assessing potential biases that could arise in using this approach., Objective: This study aimed to guide the assessment of biases that arise when estimating the population sizes of hidden populations using the SMM combined with respondent-driven sampling (RDS) surveys., Methods: We conducted RDS surveys at 9 sites in late 2013, where the Sisters with a Voice program (the program), which collects program visit data of FSWs, was also present. Using the SMM, we obtained PSEs for FSWs at each site by dividing the number of FSWs who attended the program, based on program records, by the RDS-II weighted proportion of FSWs who reported attending this program in the previous 6 months in the RDS surveys. Both the RDS weighting and SMM make a number of assumptions, potentially leading to biases if the assumptions are not met. To test these assumptions, we used convergence and bottleneck plots to assess seed dependence of RDS-II proportion estimates, chi-square tests to assess if there was an association between the characteristics of FSWs and their knowledge of program existence, and logistic regression to compare the characteristics of FSWs attending the program with those recruited to RDS surveys., Results: The PSEs ranged from 194 (95% CI 62-325) to 805 (95% CI 456-1142) across 9 sites from May to November 2013. The 95% CIs for the majority of sites were wide. In some sites, the RDS-II proportion of women who reported program use in the RDS surveys may have been influenced by the characteristics of selected seeds, and we also observed bottlenecks in some sites. There was no evidence of association between characteristics of FSWs and knowledge of program existence, and in the majority of sites, there was no evidence that the characteristics of the populations differed between RDS and program data., Conclusions: We used a series of rigorous methods to explore potential biases in our PSEs. We were able to identify the biases and their potential direction, but we could not determine the ultimate direction of these biases in our PSEs. We have evidence that the PSEs in most sites may be biased and a suggestion that the bias is toward underestimation, and this should be considered if the PSEs are to be used. These tests for bias should be included when undertaking population size estimation using the SMM combined with RDS surveys., (©Sungai T Chabata, Elizabeth Fearon, Emily L Webb, Helen A Weiss, James R Hargreaves, Frances M Cowan. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 15.06.2020.)

Introduction: Adolescent girls and young women (AGYW), including those who sell sex in sub-Saharan Africa, are especially vulnerable to HIV. Reaching them with effective prevention is a programmatic priority. The HIV prevention cascade can be used to track intervention coverage, and identify gaps and opportunities for programme strengthening. The aim of this study was to characterise gaps in condom use and identify reasons underlying these gaps among young women who sell sex (YWSS) in Zimbabwe using data from enrolment into an impact evaluation of the DREAMS programme. DREAMS provided a package of biomedical, social and economic interventions to AGYW aged 10 to 24 with the aim of reducing HIV incidence., Methods: In 2017, we recruited YWSS aged 18 to 24 using respondent-driven sampling in six sites across Zimbabwe. We measured knowledge about efficacy of, access to, and effective (consistent) use of condoms with the most recent three sexual partners, separately by whether YWSS self-identified as female sex workers (FSW) or not. Among YWSS without knowledge about efficacy of, not having access to, and not effectively using condoms, we described the potential reasons underlying the gaps in the condom cascade. To identify socio-demographic characteristics associated with effective condom use, we used logistic regression modelling. All analyses were RDS-II weighted and restricted to YWSS testing HIV-negative at enrolment., Results: We enrolled 2431 YWSS. Among 1842 (76%) YWSS testing HIV-negative, 66% (n = 1221) self-identified as FSW. 89% of HIV-negative YWSS demonstrated knowledge about efficacy of condoms, 80% reported access to condoms and 58% reported using condoms consistently with the three most recent sexual partners. Knowledge about efficacy of and effective use of condoms was similar regardless of whether or not YWSS self-identified as FSW, but YWSS self-identifying as FSW reported better access to condoms compared to those who did not (87% vs 68%; age- and site-adjusted (adjOR) = 2.69; 95% CI: 2.01 to 3.60; p < 0.001). Women who reported experiencing sexual violence in the past year and common mental disorder in the past week were less likely to use condoms consistently (43% vs. 60%; adjOR = 0.49; 95% CI: 0.35 to 0.68; p < 0.001) and (51% vs. 61%; adjOR = 0.76; 95% CI: 0.60 to 0.97; p = 0.029), respectively., Conclusions: Despite high knowledge about efficacy of and access to condoms, there remain large gaps in self-reported consistent condom use among YWSS. Addressing the structural determinants of YWSS' inconsistent condom use, including violence, could reduce this gap. YWSS who do not self-identify as FSW have less access to condoms and may require additional programmatic intervention., (© 2020 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Introduction: Surveillance of recent HIV infections in national testing services has the potential to inform primary prevention programming activities. Focusing on procedures required to accurately determine recent infection, and the potential for recent infection surveillance to inform prevention efforts, we present the results of three independent but linked pilots of recency testing., Methods: To distinguish recently acquired HIV infection from long-standing infection, in 2018 we applied a Recent Infection Testing Algorithm that combined a laboratory-based Limiting Antigen Avidity Enzyme Immunoassay with clinical information (viral-load; history of prior HIV diagnosis; antiretroviral therapy-exposure). We explored potential misclassification of test results and analysed the characteristics of participants with recent infection. We applied the algorithm in antenatal clinics providing prevention of mother-to-child transmission services in Siaya County, Kenya, outreach sites serving female sex workers in Zimbabwe, and routine HIV testing and counselling facilities in Nairobi, Kenya. In Nairobi, we also conducted recency testing among partners of HIV-positive participants., Results: In Siaya County, 2.3% (10/426) of HIV-positive pregnant women were classified as recent. A risk factor analysis comparing women testing recent with those testing HIV-negative found women in their first trimester were significantly more likely to test recent than those in their second or third trimester. In Zimbabwe, 10.5% (33/313) of female sex workers testing HIV-positive through the outreach programme were classified recent. A risk factor analysis of women testing recent versus those testing HIV-negative, found no strong evidence of an association with recent infection. In Nairobi, among 532 HIV-positive women and men, 8.6% (46) were classified recent. Among partners of participants, almost a quarter of those who tested HIV-positive were classified as recent (23.8%; 5/21). In all three settings, the inclusion of clinical information helped improve the positive predictive value of recent infection testing by removing cases that were likely misclassified., Conclusions: We successfully identified recently acquired infections among persons testing HIV-positive in routine testing settings and highlight the importance of incorporating additional information to accurately classify recent infection. We identified a number of groups with a significantly higher proportion of recent infection, suggesting recent infection surveillance, when rolled-out nationally, may help in further targeting primary prevention efforts., (© 2020 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Introduction: Across sub-Saharan Africa, selling sex puts young women at high risk of HIV. Some young women who sell sex (YWSS) may self-identify as sex workers, while others may not, having implications for how to reach them with HIV prevention. We describe characteristics, sexual behaviours and health service use of YWSS in Zimbabwe, comparing women who identified as female sex workers (FSW) and women who did not (non-identifying-YWSS), and explore factors associated with HIV infection., Methods: We analysed data from respondent-driven sampling (RDS) surveys among YWSS aged 18 to 24 implemented in six sites in Zimbabwe from April to July 2017. RDS was used to enrol YWSS into an impact evaluation of the multi-country DREAMS (Determined, Resilient, Empowered, AIDS-free, Mentored and Safe) Partnership, which provides comprehensive HIV prevention programming to adolescent girls and young women. Women completed an interviewer-administered questionnaire and were offered HIV testing services. We used logistic regression (RDS-II-weighted, normalized by site) to identify factors associated with prevalent HIV infection., Results: Forty-four seeds recruited 2387 YWSS. RDS-adjusted HIV prevalence was 24%; 67% of women identified as FSW. FSW were older and had lower educational attainment than non-identifying-YWSS. While 40% of FSW reported 10+ clients in the previous month, 9% of non-identifying-YWSS did so. FSW were more likely to have accessed HIV-related services, including HIV testing in the last six months (FSW: 70%; non-identifying-YWSS: 60%). Over half of all YWSS described selling sex as their main financial support (FSW: 88%; non-identifying YWSS: 54%). Increasing age, lower educational attainment, younger age of first selling sex and higher number of clients in the previous month were associated with prevalent HIV., Conclusions: YWSS in Zimbabwe have a high prevalence of HIV, reported high numbers of sexual partners and depend financially on selling sex. Non-identifying-YWSS differed socio-demographically to FSW, yet factors associated with HIV risk were similar for all women. Women not identifying as FSW were less likely to access services, suggesting they should be prioritized for HIV prevention. Network-based recruitment may enhance their inclusion in programmes, like DREAMS, which aim to reach young women at highest-risk with comprehensive health, HIV prevention and social protection services., (© 2019 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Introduction: UNAIDS' goal of ending AIDS by 2030 is unreachable without better targeting of testing, prevention and care. Female sex workers (FSW) in Zimbabwe are at high risk of HIV acquisition and transmission. Here, we report on collated programme and research data from Zimbabwe's national sex work programme. We also assess the potential for wider population impact of FSW programmes by modelling the impact on HIV incidence of eliminating transmission through FSW (i.e. calculate the population attributable fraction of incidence attributable to sex work)., Methods: Descriptive analyses of individual-level programme data collected from FSW between 2009 and June 2018 are triangulated with data collected through 37 respondent driven sampling surveys from 19 sites in Zimbabwe 2011 to 2017. We describe programme coverage, uptake, retention and patterns of sex work behaviour and gaps in service provision. An individual-level stochastic simulation model is used to reconstruct the epidemic and then the incidence compared with the counter-factual trend in incidence from 2010 had transmission through sex work been eliminated from that date., Results: Sisters has reached >67,000 FSW since 2009, increasing attendance as number of sites, programme staff and peer educators were increased. Over 57% of all FSW estimated to be working in Zimbabwe in 2017 (n = 40,000) attended the programme at least once. The proportion of young FSW reached has increased with introduction of the "Young Sisters programme." There are no clear differences in pattern of sex work across settings. Almost all women report condom use with clients at last sex (95%); however, consistent condom use with clients in the last month varies from 52% to 95% by site. Knowledge of HIV-positive status has increased from 48 to 78% between 2011 and 2016, as has prevalence of ART use among diagnosed women (29 to 67%). Although subject to uncertainty, modelling suggests that 70% (90% range: 32%, 93%) of all new infections in Zimbabwe from 2010 are directly or indirectly attributable to transmission via sex work., Conclusions: It is feasible to increase coverage and impact of sex work programming through community-led scale-up of evidence-based interventions. Eliminating transmission through commercial sex would likely have a substantial impact on new infections occurring more widely across Zimbabwe., (© 2019 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Young female sex-workers (FSW) aged 18-24 are at high risk of HIV due to high numbers of sexual partners, difficulty negotiating condom use, increased risk of gender-based violence, and limited access to services. Here we describe changes in sexual behaviours among young FSW across Zimbabwe between 2013 and 2016, and risk factors for prevalent HIV in 2013 and 2016. FSW ≥ 18 years were recruited using respondent-driven sampling in 14 sites across Zimbabwe in 2013 and 2016 as part of the SAPPH-IRe trial. We collected data on socio-demographics and sexual behaviour and offered HIV testing. Statistical analyses were RDS-II weighted. Characteristics of young FSW aged 18-24 were described, stratified by age. Logistic regression was used to assess difference in sexual behaviours by reported HIV status between 2013 and 2016, and to explore associations with prevalent HIV in 2013 and 2016. 656 young FSW were recruited in 2013 and 503 in 2016. Characteristics of young FSW were similar across both surveys. HIV prevalence was similar at both time points (35% vs 36%) and rose steeply with age. Compared to young FSW in 2013, reported condom-less sex with a steady partner and condom-less sex with clients was higher in 2016 among women self-reporting HIV negative status (OR = 6.41; 95%CI: 3.40-12.09; P<0.001) and (OR = 1.69; 95%CI: 1.14-2.51, P = 0.008), respectively, but not among young FSW self-reporting HIV positive status (OR = 2.35; 95%CI: 0.57-9.76; P = 0.236) and (OR = 1.87; 95%CI: 0.74-4.74; P = 0.186). After adjusting for age in 2016, young FSW who had ever been married had increased odds of testing HIV positive (OR = 1.88; 95% CI 1.04-3.39; P = 0.036) compared with those who had never married. Young FSW who completed secondary education or higher were less likely to test HIV positive (OR = 0.41; 95% CI 0.20-0.83; P = 0.012) compared with those with primary education or less. Young FSW remain at very high risk of HIV. Strategies to identify young FSW when they first start selling and refer them into services that address their economic, social and sexual vulnerabilities are critical.

Background: "HIV prevention cascades" have been proposed to support programs by identifying gaps in demand for, access to, and capability to adhere to HIV prevention tools, but there are few empirical examples to guide development. We apply a prevention cascade framework to examine prevention coverage and factors associated with condoms and/or PrEP adherence among female sex workers., Setting: Seven sites across Zimbabwe., Methods: Seven respondent-driven sampling surveys from the intervention sites of a pragmatic cluster-randomized trial in Zimbabwe in 2016 were analyzed, and 611/1439 women testing HIV-negative included. We operationalized key components of an HIV prevention cascade including demand, supply, and capability to adhere to 2 tools for HIV prevention: condoms and pre-exposure prophylaxis (PrEP). We used adjusted logistic regression to identify determinants of adherence to condoms and PrEP in turn, examining the effect of adherence to one tool on adherence to the other., Results: There were 343/611, 54.7%, women reporting adherence to condoms and/or PrEP, leaving almost half uncovered. Although women were aware that condoms prevented HIV and reported good access to them, only 45·5% reported full adherence to condom use. For PrEP, a new technology, there were gaps along all 3 domains of demand, supply, and adherence. Alcohol use decreased adherence to PrEP and condoms. Younger and newer entrants to sex work were less likely to take PrEP every day., Conclusions: HIV prevention programming among female sex workers in Zimbabwe could consider increasing awareness of PrEP alongside supply, alcohol use interventions, and approaches to engaging younger women.

Background: While guidance exists for obtaining population size estimates using multiplier methods with respondent-driven sampling surveys, we lack specific guidance for making sample size decisions., Objective: To guide the design of multiplier method population size estimation studies using respondent-driven sampling surveys to reduce the random error around the estimate obtained., Methods: The population size estimate is obtained by dividing the number of individuals receiving a service or the number of unique objects distributed (M) by the proportion of individuals in a representative survey who report receipt of the service or object (P). We have developed an approach to sample size calculation, interpreting methods to estimate the variance around estimates obtained using multiplier methods in conjunction with research into design effects and respondent-driven sampling. We describe an application to estimate the number of female sex workers in Harare, Zimbabwe., Results: There is high variance in estimates. Random error around the size estimate reflects uncertainty from M and P, particularly when the estimate of P in the respondent-driven sampling survey is low. As expected, sample size requirements are higher when the design effect of the survey is assumed to be greater., Conclusions: We suggest a method for investigating the effects of sample size on the precision of a population size estimate obtained using multipler methods and respondent-driven sampling. Uncertainty in the size estimate is high, particularly when P is small, so balancing against other potential sources of bias, we advise researchers to consider longer service attendance reference periods and to distribute more unique objects, which is likely to result in a higher estimate of P in the respondent-driven sampling survey., (©Elizabeth Fearon, Sungai T Chabata, Jennifer A Thompson, Frances M Cowan, James R Hargreaves. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 14.09.2017.)