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.

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.

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Population-level impact of Zimbabwe's National Behavioural Change Programme.

OBJECTIVE: To assess the impact of Zimbabwe's National Behavioural Change Programme (NBCP) on biological and behavioral outcomes. METHODS: Representative household biobehavioral surveys of 18- to 44-year-olds were conducted in randomly selected enumeration areas in 2007 and 2011 to 2012. We examined program impact on HIV prevalence among young women, nonregular partnerships, condom use with nonregular partners, and HIV testing, distinguishing between highly exposed and low-exposed communities and individuals. We conducted (1) difference-in-differences analyses with communities as unit of analysis and (2) analyses of key outcomes by individual-level program exposure. RESULTS: Four thousand seven hundred seventy-six people were recruited in 2007 and 10,059 in 2011 to 2012. We found high exposure to NBCP in 2011. Prevalence of HIV and reported risky behaviors declined between 2007 and 2011. Community-level analyses showed a smaller decline in HIV prevalence among young women in highly exposed areas (11.0%-10.1%) than low-exposed areas (16.9%-10.3%, P = 0.078). Among young men, uptake of nonregular partners declined more in highly exposed areas (25%-16.8%) than low-exposed areas (21.9%-20.7%, P = 0.055) and HIV testing increased (27.2%-46.1% vs. 31.0%-34.4%, P = 0.004). Individual-level analyses showed higher reported condom use with nonregular partners among highly exposed young women (53% vs. 21% of unexposed counterparts, P = 0.037). CONCLUSIONS: We conducted the first impact evaluation of a NBCP and found positive effects of program exposure on key behaviors among certain gender and age groups. HIV prevalence among young women declined but could not be attributed to program exposure. These findings suggest substantial program effects regarding demand creation and justify program expansion.

Engagement with HIV prevention treatment and care among female sex workers in Zimbabwe: a respondent driven sampling survey.

OBJECTIVES: To determine the HIV prevalence and extent of engagement with HIV prevention and care among a representative sample of Zimbabwean sex workers working in Victoria Falls, Hwange and Mutare. DESIGN: Respondent driven sampling (RDS) surveys conducted at each site. METHODS: Sex workers were recruited using respondent driven sampling with each respondent limited to recruiting 2 peers. Participants completed an interviewer-administered questionnaire and provided a finger prick blood sample for HIV antibody testing. Statistical analysis took account of sampling method. RESULTS: 870 women were recruited from the three sites. HIV prevalence was between 50 and 70%. Around half of those confirmed HIV positive were aware of their HIV status and of those 50-70% reported being enrolled in HIV care programmes. Overall only 25-35% of those with laboratory-confirmed HIV were accessing antiretroviral therapy. Among those reporting they were HIV negative, 21-28% reported having an HIV test in the last 6 months. Of those tested HIV negative, most (65-82%) were unaware of their status. Around two-thirds of sex workers reported consistent condom use with their clients. As in other settings, sex workers reported high rates of gender based violence and police harassment. CONCLUSIONS: This survey suggests that prevalence of HIV is high among sex workers in Zimbabwe and that their engagement with prevention, treatment and care is sub-optimal. Intensifying prevention and care interventions for sex workers has the potential to markedly reduce HIV and social risks for sex workers, their clients and the general population in Zimbabwe and elsewhere in the region.

"You are wasting our drugs": health service barriers to HIV treatment for sex workers in Zimbabwe.

BACKGROUND: Although disproportionately affected by HIV, sex workers (SWs) remain neglected by efforts to expand access to antiretroviral treatment (ART). In Zimbabwe, despite the existence of well-attended services targeted to female SWs, fewer than half of women diagnosed with HIV took up referrals for assessment and ART initiation; just 14% attended more than one appointment. We conducted a qualitative study to explore the reasons for non-attendance and the high rate of attrition. METHODS: Three focus group discussions (FGD) were conducted in Harare with HIV-positive SWs referred from the 'Sisters with a Voice' programme to a public HIV clinic for ART eligibility screening and enrolment. Focus groups explored SWs' experiences and perceptions of seeking care, with a focus on how managing HIV interacted with challenges specific to being a sex worker. FGD transcripts were analyzed by identifying emerging and recurring themes that were specifically related to interactions with health services and how these affected decision-making around HIV treatment uptake and retention in care. RESULTS: SWs emphasised supply-side barriers, such as being demeaned and humiliated by health workers, reflecting broader social stigma surrounding their work. Sex workers were particularly sensitive to being identified and belittled within the health care environment. Demand-side barriers also featured, including competing time commitments and costs of transport and some treatment, reflecting SWs' marginalised socio-economic position. CONCLUSION: Improving treatment access for SWs is critical for their own health, programme equity, and public health benefit. Programmes working to reduce SW attrition from HIV care need to proactively address the quality and environment of public services. Sensitising health workers through specialised training, refining referral systems from sex-worker friendly clinics into the national system, and providing opportunities for SW to collectively organise for improved treatment and rights might help alleviate the barriers to treatment initiation and attention currently faced by SW.

The Regai Dzive Shiri project: results of a randomized trial of an HIV prevention intervention for youth.

BACKGROUND: HIV prevention among young people in southern Africa is a public health priority. There is little rigorous evidence of the effectiveness of different intervention approaches. We describe findings of a cluster randomized trial of a community-based, multicomponent HIV, and reproductive health intervention aimed at changing social norms for adolescents in rural Zimbabwe. METHODS: Thirty rural communities were randomized to early or deferred implementation of the intervention in 2003. Impact was assessed in a representative survey of 18-22-year-olds after 4 years. Participants self-completed a questionnaire and gave a dried blood spot sample for HIV and herpes simplex virus-2 (HSV-2) antibody testing. Young women had a urinary pregnancy test. Analyses were by intention-to-treat and were adjusted for clustering. FINDINGS: Four thousand six hundred and eighty-four, 18-22-year-olds participated in the survey (97.1% of eligible candidates, 55.5% women). Just over 40% had been exposed to at least 10 intervention sessions. There were modest improvements in knowledge and attitudes among young men and women in intervention communities, but no impact on self-reported sexual behavior. There was no impact of the intervention on prevalence of HIV or HSV-2 or current pregnancy. Women in intervention communities were less likely to report ever having been pregnant. INTERPRETATION: Despite an impact on knowledge, some attitudes, and reported pregnancy, there was no impact of this intervention on HIV or HSV-2 prevalence, further evidence that behavioral interventions alone are unlikely to be sufficient to reverse the HIV epidemic. The challenge remains to find effective HIV prevention approaches for young people in the face of continued and unacceptably high HIV incidence, particularly among young women.

The Regai Dzive Shiri Project: a cluster randomised controlled trial to determine the effectiveness of a multi-component community-based HIV prevention intervention for rural youth in Zimbabwe--study design and baseline results.

OBJECTIVE: To assess the effectiveness of a community-based HIV prevention intervention for adolescents in terms of its impact on (1) HIV and Herpes simplex virus type 2 (HSV-2) incidence and on rates of unintended pregnancy and (2) reported sexual behaviour, knowledge and attitudes. METHODS: Cluster randomised trial of a multi-component HIV prevention intervention for adolescents based in rural Zimbabwe. Thirty communities were selected and randomised in 2003 to early or deferred intervention implementation. A baseline bio-behavioural survey was conducted among 6791 secondary school pupils (86% of eligibles) prior to intervention implementation. RESULTS: Baseline prevalences were 0.8% (95% CI: 0.6-1.0) for HIV and 0.2% (95% CI: 0.1-0.3%) for HSV-2. Four girls (0.12%) were pregnant. There was excellent balance between study arms. Orphans who made up 35% of the cohort were at increased risk of HIV [age-sex adjusted odds ratio 3.4 (95% CI: 1.7-6.5)]. 11.9% of young men and 2.9% of young women reported that they were sexually active (P < 0.001); however, there were inconsistencies in the sexual behaviour data. Girls were less likely to know about reproductive health issues than boys (P < 0.001) and were less likely to have used and to be able to access condoms (P < 0.001). CONCLUSION: This is one of the first rigorous evaluations of a community-based HIV prevention intervention for young people in southern Africa. The low rates of HIV suggest that the intervention was started before this population became sexually active. Inconsistency and under-reporting of sexual behaviour re-emphasise the importance of using externally validated measures of sexual risk reduction in behavioural intervention studies.