Female Sex Workers In Zimbabwe Research Articles

Gains and gaps: addressing HIV in diverse sex worker groups

Over the past four decades of the HIV pandemic, diverse groups of sex workers have been disproportionately affected across settings. 1 UNAIDSHIV and sex work: human rights fact sheets series. https://www.unaids.org/sites/default/files/media_asset/05-hiv-human-rights-factsheet-sex-work_en.pdfDate: 2021 Date accessed: June 1, 2023 Google Scholar Social and structural factors including the criminalisation of sex work, financial insecurity, and intersectional stigma, discrimination, and violence have been identified as key drivers of sex workers' disproportionate HIV risk and poor treatment outcomes. 2 Shannon K Crago A-L Baral SD et al. The global response and unmet actions for HIV and sex workers. Lancet. 2018; 392: 698-710 Summary Full Text Full Text PDF PubMed Scopus (129) Google Scholar Although community-driven combination prevention interventions have shown promise in reducing new HIV infections and improving HIV care and treatment outcomes among sex workers, 3 Kerrigan D Kennedy CE Morgan-Thomas R et al. A community empowerment approach to the HIV response among sex workers: effectiveness, challenges, and considerations for implementation and scale-up. Lancet. 2015; 385: 172-185 Summary Full Text Full Text PDF PubMed Scopus (209) Google Scholar investments to bring these efforts to scale have lagged far behind historical and current needs. Temporal trends in, and risk factors for, HIV seroconversion among female sex workers accessing Zimbabwe's national sex worker programme, 2009–19: a retrospective cohort analysis of routinely collected HIV testing dataWe 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. Full-Text PDF Open AccessHIV prevalence, risk behaviour, and treatment and prevention cascade outcomes among cisgender men, transgender women, and transgender men who sell sex in Zimbabwe: a cross-sectional analysis of programme dataThese 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. Full-Text PDF

Temporal trends in, and risk factors for, HIV seroconversion among female sex workers accessing Zimbabwe's national sex worker programme, 2009–19: a retrospective cohort analysis of routinely collected HIV testing data

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. 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. 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. 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. 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.

Interpreting declines in HIV test positivity: an analysis of routine data from Zimbabwe's national sex work programme, 2009-2019.

IntroductionEarly 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.MethodsWe 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.ResultsDuring 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).ConclusionsTest 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.

Utilisation of HIV services by female sex workers in Zimbabwe during the COVID-19 pandemic: a descriptive phenomenological study

This study focuses on female sex workers as a key population group that suffers a degree of vulnerability according to the World Health Organisation (WHO). Key populations refer to people at heightened risk of contracting the human immunodeficiency virus (HIV) due to specific behaviours and social and legal environments which increase their vulnerability to the virus. Key populations are disproportionately affected by HIV, yet they have less access to HIV services compared to the general population. The coronavirus (COVID-19) lockdown and its restrictive measures have further widened the inequalities and gaps in accessing HIV services for this group. A descriptive phenomenological study was undertaken to explore female sex workers’ experiences of utilisation of HIV services during COVID-19. The study setting was the Bulawayo Metropolitan Province, Zimbabwe. Data were collected through in-depth individual interviews with 10 female sex workers. Purposive sampling coupled with snowballing was utilised for recruiting participants. Data were analysed guided by the seven-step Colaizzi technique. Rigour was ensured through adhering to Lincoln and Guba’s trustworthiness criteria. The study found that the COVID-19 pandemic adversely affected the livelihoods of sex workers and their utilisation of HIV services. There was limited access to HIV services due to an initial lack of travel authorisation letters and financial challenges experienced by study participants. In addition, the quality of care in health care facilities was further compromised by poor screening processes and reduced provider-client interactions. Maintaining access to HIV services for female sex workers during pandemics is critical for the country to attain HIV epidemic control.

Differentiated prevention and care to reduce the risk of HIV acquisition and transmission among female sex workers in Zimbabwe: study protocol for the \u2018AMETHIST\u2019 cluster randomised trial

BackgroundFemale 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.MethodsThe 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.DiscussionInnovative 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 registrationPan African Clinical Trials Registry PACTR202007818077777. Registered on 2 July 2020.

How do you expect us to survive? Lamentation of female sex workers in Zimbabwe during COVID-19 lockdown.

The restrictive measures taken to curb and mitigate the spread of the corona virus (COVID-19) had negative implications on the vulnerable populations. Of the latter, the most severely affected were sex workers, whose work venues and customers were locked down. This descriptive phenomenological study explored effects of COVID-19 on female sex workers in Bulawayo, Zimbabwe. Snowballing sampling was used to recruit participants. Data were collected through in-depth face-to-face individual interviews with ten female sex workers. The sample size was determined by data saturation. Colaizzi's seven-step content analysis approach was followed to guide data analysis. Rigour was ensured by adhering to Guba and Lincoln's trustworthiness criteria. The study found that the measures impacted negatively on sex workers' income, making it difficult for them to get money for food and rentals. In response, some sex workers adopted innovative entrepreneurship. Others engaged in risky sexual behaviours, further aggravating their situation emotionally and psychologically. It is recommended that the government and policy makers provide psychosocial and economic support to protect the rights of female sex workers in order to maintain the gains made in HIV response.

Estimation of HIV incidence from analysis of HIV prevalence patterns among female sex workers in Zimbabwe.

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). We pooled data from FSW aged 18-39 participating in respondent-driven sampling surveys conducted in Zimbabwe between 2011 and 2017. 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. 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. 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.

Experiences and lessons learned from the real-world implementation of an HIV recent infection testing algorithm in three routine service-delivery settings in Kenya and Zimbabwe

IntroductionTesting for recent HIV infection can distinguish recently acquired infection from long-standing infections. Given current interest in the implementation of recent infection testing algorithms (RITA), we report our experiences in implementing a RITA in three pilot studies and highlight important issues to consider when conducting recency testing in routine settings.MethodsWe applied a RITA, incorporating a limited antigen (LAg) avidity assay, in different routine HIV service-delivery settings in 2018: antenatal care clinics in Siaya County, Kenya, HIV testing and counselling facilities in Nairobi, Kenya, and female sex workers clinics in Zimbabwe. Discussions were conducted with study coordinators, laboratory leads, and facility-based stakeholders to evaluate experiences and lessons learned in relation to implementing recency testing.ResultsIn Siaya County 10/426 (2.3%) of women testing HIV positive were classified as recent, compared to 46/530 (8.7%) of women and men in Nairobi and 33/313 (10.5%) of female sex workers in Zimbabwe. Across the study setting, we observed differences in acceptance, transport and storage of dried blood spot (DBS) or venous blood samples. For example, the acceptance rate when testing venous blood was 11% lower than when using DBS. Integrating our study into existing services ensured a quick start of the study and kept the amount of additional resources required low. From a laboratory perspective, the LAg avidity assay was initially difficult to operationalise, but developing a network of laboratories and experts to work together helped to improve this. A challenge that was not overcome was the returning of RITA test results to clients. This was due to delays in laboratory testing, the need for multiple test results to satisfy the RITA, difficulties in aligning clinic visits, and participants opting not to return for test results.ConclusionWe completed three pilot studies using HIV recency testing based on a RITA in Kenya and Zimbabwe. The main lessons we learned were related to sample collection and handling, LAg avidity assay performance, integration into existing services and returning of test results to participants. Our real-world experience could provide helpful guidance to people currently working on the implementation of HIV recency testing in sub-Saharan Africa.

Understanding early uptake of PrEP by female sex workers in Zimbabwe

ABSTRACT Female sex workers (FSW) are prioritised for increased access to pre-exposure prophylaxis (PrEP), although rates of uptake remain sub-optimal, particularly across Southern Africa. In the first two years of its availability in Zimbabwe, 37.1% of FSW in trial sites initiated PrEP and received at least one re-supply. We conducted a qualitative study on perceptions of PrEP among 19 early users selected from sites with varying rates of PrEP initiation. Narrative interviews examined the pathways taken by FSW from hearing about PrEP, through their decision to start taking it, and early experiences. FSW appreciated PrEP’s introduction within familiar and trusted “friendly” services tailored for sex workers and valued positive encouragement from clinic staff and peers over negative influence from family members. They also found PrEP difficult to understand at first, and feared side effects and rare adverse complications described in information leaflets. While FSW identified individual strategies for remembering to take their medication, they also relied on structured peer adherence support, leading some FSW to actively promote the method to other FSW as “PrEP champions”. Information on how early users experience a new prevention technology such as PrEP can inform design of interventions that leverage existing support structures and target key barriers.

Can HIV recent infection surveillance help us better understand where primary prevention efforts should be targeted? Results of three pilots integrating a recent infection testing algorithm into routine programme activities in Kenya and Zimbabwe.

IntroductionSurveillance 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.MethodsTo 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.ResultsIn 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.ConclusionsWe 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.

Estimating the Population Size of Female Sex Workers in Zimbabwe: Comparison of Estimates Obtained Using Different Methods in Twenty Sites and Development of a National-Level Estimate.

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.

Exploring the Association Between Mobility and Access to HIV Services Among Female Sex Workers in Zimbabwe.

Female sex workers (FSW) face structural barriers to HIV-service access, however the effect of their mobility is uncertain. Using cross-sectional data from 2839 FSW in 14 sites in Zimbabwe, we explored the association between mobility (number of trips, distance, duration) in the past 12months and five HIV-service-access outcomes: exposure to community mobilisation, clinic attendance, HIV testing, antiretroviral treatment initiation, and viral suppression (< 1000 copies per mL). We used modified-Poisson regression, and natural-effects models to estimate how the effect oftrip frequency was mediated by distance and duration away. Each additional trip in 12months was associated with increased community-mobilisation-event attendance (adjusted RR 1.08, 95% CI 1.04-1.12) and attending clinic two-or-more times (adjusted RR 1.02, 95% CI 1.00-1.05). There was little evidence of any other associations, or of mediation. Our findings are consistent with literature that found the effects of mobility to vary by context and outcome. This is the first study to consider many FSW-mobility and HIV-service-access measures together. Future research on mobility and health-related behaviour should use a spectrum of measures.

How Can Programs Better Support Female Sex Workers to Avoid HIV Infection in Zimbabwe? A Prevention Cascade Analysis.

"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. Seven sites across Zimbabwe. 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. 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. 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.

Where are the positives? HIV testing in sub-Saharan Africa in the era of test and treat.

Where are the positives? HIV testing in sub-Saharan Africa in the era of test and treat.

Engagement in HIV Care Among Young Female Sex Workers in Zimbabwe.

Young female sex workers (FSWs) are at greater HIV risk than their older counterparts. Yet, the extent of their engagement with HIV services is largely unknown. We compared engagement among FSWs aged 18-24 years with those 25 years and older. We used respondent-driven sampling to recruit FSWs from 14 communities in Zimbabwe from November to December 2013. We collected data on demographics, behavior, service uptake, and HIV and viral load testing. Data were pooled and weighted using respondent-driven sampling-2 estimation. We analyzed HIV care cascade variables by age group. To identify potential drivers of younger FSW service use, we explored factors associated with knowing one's HIV status. Among 2617 participants, mean age was 31 years and 26% were 18-24 years. Over half of FSWs initiated sex work before the age of 25 years. Overall HIV prevalence was 59% but was lower among younger FSWs (35% vs 67%, P < 0.01). Younger HIV-infected FSWs were significantly less engaged at each step of the care cascade. Among younger FSWs reporting antiretroviral therapy use, 62% had an undetectable viral load compared with 79% in older FSWs. In multivariable regression, young FSWs encouraged to have an HIV test by another FSW (adjusted odds ratio = 2.54; 95% confidence interval: 1.44 to 4.50), and those with no recent clients (adjusted odds ratio = 4.31; 95% confidence interval: 1.30 to 14.33) were more likely to report knowing their status. The high proportion of FSWs initiating sex work before the age of 25 years and their lower engagement in HIV services highlights the importance of considering this vulnerable population in HIV programming. Implementing targeted services tailored to the unique needs of young FSWs is a public health imperative.

Targeted combination prevention to support female sex workers in Zimbabwe accessing and adhering to antiretrovirals for treatment and prevention of HIV (SAPPH-IRe): a cluster-randomised trial

Strengthening engagement of female sex workers with health services is needed to eliminate HIV. We assessed the efficacy of a targeted combination intervention for female sex workers in Zimbabwe. We did a cluster-randomised trial from 2014 to 2016. Clusters were areas surrounding female sex worker clinics and were enrolled in matched pairs. Sites were randomly assigned (1:1) to receive usual care (free sexual-health services supported by peer educators, including HIV testing on demand, referral for antiretroviral therapy [ART], and health education) or an intervention that supported additional regular HIV testing, on-site initiation of ART, pre-exposure prophylaxis, adherence, and intensified community mobilisation. The primary outcome was the proportion of all female sex workers with HIV viral load 1000 copies per mL or greater, assessed through respondent-driven sampling surveys. We used an adapted cluster-summary approach to estimate risk differences. This trial is registered with Pan African Clinical Trials Registry, number PACTR201312000722390. We randomly assigned 14 clusters to usual care or the intervention (seven in each group). 3612 female sex workers attended clinics in the usual-care clusters and 4619 in the intervention clusters during the study. Half as many were tested (1151 vs 2606) and diagnosed as being HIV positive (546 vs 1052) in the usual-care clusters. The proportion of all female sex workers with viral loads of 1000 copies per mL or greater fell in both study groups (from 421 [30%] of 1363 to 279 [19%] of 1443 in the usual-care group and from 399 [30%] of 1303 to 240 [16%] of 1439 in the intervention group), but with a risk difference at the end of the assessment period of only -2·8% (95% CI -8·1 to 2·5, p=0·23). Among HIV-positive women, the proportions with viral loads less than 1000 copies per mL were 590 (68%) of 869 in the usual-care group and 588 (72%) of 828 in the intervention group at the end of the assessment period, adjusted risk difference of 5·3% (95% CI -4·0 to 14·6, p=0·20). There were no adverse events. Our intervention of a dedicated programme for female sex workers led to high levels of HIV diagnosis and treatment. Further research is needed to optimise programme content and intensity for the broader population. UN Population Fund (through Zimbabwe's Integrated Support Fund funded by UK Department for International Development, Irish Aid, and Swedish International Development Cooperation Agency).

The HIV Care Cascade Among Female Sex Workers in Zimbabwe: Results of a Population-Based Survey From the Sisters Antiretroviral Therapy Programme for Prevention of HIV, an Integrated Response (SAPPH-IRe) Trial.

Female sex workers (FSW) in sub-Saharan Africa have a higher prevalence of HIV than other women of reproductive age. Social, legal, and structural barriers influence their access to care. Little is known about the HIV diagnosis and care cascade in most countries in Southern Africa. We aimed to describe the HIV diagnosis and care cascade among FSW in Zimbabwe. We conducted cross-sectional respondent driven sampling (RDS) surveys of FSW in 14 sites across Zimbabwe as the baseline for a cluster-randomised controlled trial investigating a combination HIV prevention and care package. We administered a questionnaire, tested women for HIV and measured viral load. We report the mean, minimum, and maximum respondent-driven sampling-2 weighted site values. The survey included 2722 women, approximately 200 per site. The mean HIV prevalence was 57.5% (42.8-79.2 site minimum and maximum). Of HIV-positive women, 64.0% (51.6-73.7) were aware of their status, 67.7% (53.4-84.1) of these reported taking antiretroviral therapy, and 77.8% (64.4-90.8) of these had a suppressed HIV viral load (<1000 copies/mL). Among all HIV-positive women, 49.5% had a viral load < 1000 copies/mL. Although most HIV-positive women aware of their status are accessing antiretroviral therapy, 36.0% of HIV-positive women are unaware of their status and 29.3% of all FSW have an unsuppressed HIV viral load. Investigation and investment into models of testing, treatment, and care are necessary to reach UNAIDS targets for HIV elimination.

Implementation and Operational Research: Cohort Analysis of Program Data to Estimate HIV Incidence and Uptake of HIV-Related Services Among Female Sex Workers in Zimbabwe, 2009-2014.

HIV epidemiology and intervention uptake among female sex workers (FSW) in sub-Saharan Africa remain poorly understood. Data from outreach programs are a neglected resource. Analysis of data from FSW consultations with Zimbabwe's National Sex Work program, 2009-2014. At each visit, data were collected on sociodemographic characteristics, HIV testing history, HIV tests conducted by the program and antiretroviral (ARV) history. Characteristics at first visit and longitudinal data on program engagement, repeat HIV testing, and HIV seroconversion were analyzed using a cohort approach. Data were available for 13,360 women, 31,389 visits, 14,579 reported HIV tests, 2750 tests undertaken by the program, and 2387 reported ARV treatment initiations. At first visit, 72% of FSW had tested for HIV; 50% of these reported being HIV positive. Among HIV-positive women, 41% reported being on ARV. 56% of FSW attended the program only once. FSW who had not previously had an HIV-positive test had been tested within the last 6 months 27% of the time during follow-up. After testing HIV positive, women started on ARV at a rate of 23/100 person years of follow-up. Among those with 2 or more HIV tests, the HIV seroconversion rate was 9.8/100 person years of follow-up (95% confidence interval: 7.1 to 15.9). Individual-level outreach program data can be used to estimate HIV incidence and intervention uptake among FSW in Zimbabwe. Current data suggest very high HIV prevalence and incidence among this group and help identify areas for program improvement. Further methodological validation is required.

Statistical design and analysis plan for an impact evaluation of an HIV treatment and prevention intervention for female sex workers in Zimbabwe: a study protocol for a cluster randomised controlled trial.

BackgroundPragmatic cluster-randomised trials should seek to make unbiased estimates of effect and be reported according to CONSORT principles, and the study population should be representative of the target population. This is challenging when conducting trials amongst ‘hidden’ populations without a sample frame. We describe a pair-matched cluster-randomised trial of a combination HIV-prevention intervention to reduce the proportion of female sex workers (FSW) with a detectable HIV viral load in Zimbabwe, recruiting via respondent driven sampling (RDS).MethodsWe will cross-sectionally survey approximately 200 FSW at baseline and at endline to characterise each of 14 sites. RDS is a variant of chain referral sampling and has been adapted to approximate random sampling. Primary analysis will use the ‘RDS-2’ method to estimate cluster summaries and will adapt Hayes and Moulton’s ‘2-step’ method to adjust effect estimates for individual-level confounders and further adjust for cluster baseline prevalence. We will adapt CONSORT to accommodate RDS. In the absence of observable refusal rates, we will compare the recruitment process between matched pairs. We will need to investigate whether cluster-specific recruitment or the intervention itself affects the accuracy of the RDS estimation process, potentially causing differential biases. To do this, we will calculate RDS-diagnostic statistics for each cluster at each time point and compare these statistics within matched pairs and time points. Sensitivity analyses will assess the impact of potential biases arising from assumptions made by the RDS-2 estimation.DiscussionWe are not aware of any other completed pragmatic cluster RCTs that are recruiting participants using RDS. Our statistical design and analysis approach seeks to transparently document participant recruitment and allow an assessment of the representativeness of the study to the target population, a key aspect of pragmatic trials. The challenges we have faced in the design of this trial are likely to be shared in other contexts aiming to serve the needs of legally and/or socially marginalised populations for which no sampling frame exists and especially when the social networks of participants are both the target of intervention and the means of recruitment.The trial was registered at Pan African Clinical Trials Registry (PACTR201312000722390) on 9 December 2013.

O18.6 A method to estimate the national prevalence of hiv-infection among female sex workers in zimbabwe by pooling data from multiplie respondent driven sampling surveys and programme consultations

Introduction Respondent driven sampling (RDS) surveys are often used to estimate site-specific HIV-prevalence among female sex workers (FSW). Methods to combine data from multiple sites to estimate national or provincial HIV-prevalence are rarely described. Methodology Using data from the Zimbabwean national FSW HIV prevention programme, working in 36 priority sites across all provinces, we estimated the average number of visits made by FSW to outreach sexual/reproductive health clinics each month at each site between January 2014–Dec 2014. We treated this variable as a proxy for the relative size of the FSW population at each site. We conducted RDS surveys with HIV testing among 200 FSW in 14 of the 36 sites, purposively selected. We used the RDS-2 analysis approach to estimate HIV prevalence in each of the 14 sites. We then combined data from the 14 sites, weighting each site by the proxy for FSW population size to provide an estimate of the national prevalence of HIV among FSW in Zimbabwe. Results The HIV prevalence across sites ranged from 43 to 79%. The unweighted mean of the site-specific prevalences was 57.5% (95% CI 51.9–62.8%). The mean number of women visiting each site per month over 2014 ranged from 16 to 87. The weighted women visiting each site per month in 2014 mean of the site-specific HIV prevalences was 58.1% (95% CI 53.8.4–62.2%). Conclusions HIV prevalence among FSW in Zimbabwe is very high but variable by site. We describe an approach to estimating national HIV prevalence from multiple site-specific surveys. Here, weighting made little difference to a mean approach though this may not always be the case. Several future refinements to the method proposed are possible and will be discussed. Disclosure of interest statement The SAPPH-IRe trial is using Truvada donated by Gilead. We have no other relationships with commercial entities to disclose.