Impressive results from Zimbabwe’s national HIV sex worker programme

09 October 2019

Sister with a Voice, Zimbabwe’s HIV programme for sex workers, has significantly increased HIV testing, treatment and viral suppression among women who sell sex.

woman on a motorbike in Africa

Zimbabwe’s community-led HIV programme for sex workers, Sisters with a Voice, has significantly improved awareness of HIV status among women who sell sex. In a new analysis of the programme from its 2009 launch, investigators found that it also improved engagement along every step of the treatment cascade.

Researchers analysed individual programme data from around 67,000 female sex workers collected between 2009 and 2018. They assess the demographic characteristics of sex workers, the impact of the Sisters’ programme and its potential impact on service gaps. To do this, they cross-referenced it against data from 37 surveys with female sex workers conducted between 2011 and 2017.

In 2017, the final complete year of the study, around 57% of female sex workers in Zimbabwe were estimated to be living with HIV. A separate study conducted by the same research team suggests around 40,000 women are selling sex in Zimbabwe at any one given time, equivalent to 1.23% of the adult female population. Half of these women live in the cities of Harare and Bulawayo.

Between 70 and 80% of sex workers included in the analysis were aged 25 and above. Most had dependent children and, apart from sex workers in Bulawayo, the majority were divorced or separated. Between 11% and 19% started selling sex before they were 18, 7% to 19% had sold sex for less than a year, and 14% to 36% had over 10 clients a week. Women typically received less than US$5 per sex act, although women in towns (but not cities) tended to receive between US$5‐10.

Community scale-up

The analysis shows how the community‐led scale‐up of Sisters with a Voice has led to impressive results. Between 2011 and 2016, the proportion of HIV-positive sex workers who were aware of their status increased from 48% to 78%, and the proportion of diagnosed female sex workers on antiretroviral treatment rose from 29% to 67%. By 2017, 82% of female sex workers on treatment were virally suppressed, and 76% of HIV-negative female sex workers had tested for HIV in the past six months.

The study also includes a projection designed to assess a sex worker programme that was fully effective, and what impact it could have had on Zimbabwe’s HIV epidemic. Working with an established modelling system, researchers used historical data to calculate HIV incidence from 2010, and then recalculated it based on a scenario where transmission through sex work had been eradicated.

Although this modelling has a high element of uncertainty – based, as it is, on the assumption that a woman who has condomless sex with more than three partners in three months is a sex worker – it suggests that 70% of all new infections in Zimbabwe from 2010 are directly or indirectly attributable to transmission via this route. It also suggests that, by 2030, there would be 85% fewer new infections had transmission through sex work been eliminated from 2010.

Although imperfect, the authors argue that this is a useful calculation because previous modelling studies have not fully considered indirect transmissions, suggesting that the likely contribution of sex work to generalised epidemics in a number of African countries has been greatly underestimated.

By September 2018, more than 67,000 women had accessed a Sisters with a Voice service at least once, totalling 194,000 clinic visits. In 2017, 24,000 women were reached, equivalent to 57% of all female sex workers in Zimbabwe. Around 8,600 of the beneficiaries lived in Harare and Bulawayo, 43% of the estimated sex worker populations in those cities.

Service gaps

The analysis also identified several service gaps. For example, although the mean number of programme visits per person increased to three during the study period, this is less than the four visits recommended by the World Health Organization.

In addition, given that the ‘optimal ratio’ of peer educator to female sex worker is 1:50, 210 extra peer educators are required in Harare to fully optimise the programme. As of 2017, only 70 were operating in the city – and this is after an intensified recruitment drive – in 2016, only 13 had been available. Despite this, findings suggest that the strategic decision to recruit younger peer educators increased the number of young sex workers reached.

The data also shows how financial and logistical constraints affected service delivery and impact. For example, a funding gap in 2012, coupled with elections in 2013, resulted in some temporary clinic closures. Between 2013 and 2016, the Sisters clinic was moved from Harare’s Mbare township to the Central Business District due to a lack of space, which also reduced attendance.

Despite significant impact in other areas, the study found condomless sex remained common. In 2017, only half of female sex workers in the programme (52%) reported consistent condom use with all clients in the past month. This suggests scaling-up pre-exposure prophylaxis (PrEP) should be a matter of priority for the Sisters programme as only 15% of HIV-negative female sex workers were on PrEP as of July 2018.

In 2017, a government-led panel estimated that the location of programme sites meant Sisters with a Voice had the potential to reach between 75% and 85% of all female sex workers in Zimbabwe.

However, since then, six sites have closed due to funding constraints. To ensure the programme continues to make impressive gains, the capacity of existing sites should be expanded, and new sites established in ‘hot spots’ not currently covered.

The study’s authors argue that, to maximise the benefits of the programme, female sex workers’ ownership of interventions must be prioritised. They highlight the importance of building community empowerment to ensure this happens, particularly among the most vulnerable sex workers, such as young women and those engaged in problematic drug or alcohol use. In addition, training public healthcare workers to treat sex workers with dignity and respect is critical.

This study has a number of important limitations. Firstly, it is not clear what proportion of women who have condomless sex with more than three partners in three months identify as sex workers. Another gap relates to the behaviour of men, as the data analysed provides little insight into how many men engage in high levels of condomless sex and what proportion of these sexual acts are transactional.

Written by Hester Phillips