JMIR Publications

ABSTRACT

Background:

HIV surveillance among key populations is a priority in all epidemic settings. Identifying the key population groups, their locations and sizes helps in understanding and prioritizing the current needs for HIV prevention, diagnosis, treatment, and care services as well as projecting future needs for those services. Female sex workers (FSWs), globally, as well as in Rwanda, are disproportionately affected by the HIV- epidemic, hence, the Rwanda HIV and AIDS National Strategic Plan (NSP 2018-2024) has adopted regular surveillance of population size estimation (PSE) of FSWs every two to three years.

Objective:

This study aims at estimating for the fourth time, the size of street- and venue-based FSW and sexually exploited minors’ population, aged 15 years and above, in Rwanda.

Methods:

In August 2022, the three-source capture-recapture (3S-CRC) method was used to estimate the FSW and sexually exploited minors’ population size in Rwanda; field work took three weeks to complete with each capture occasion lasting for a week. Sample size for each capture was calculated using MS-CRC shiny recap using inputs from previously conducted estimation exercises. At each capture round, a stratified multistage sampling process was used with administrative province as strata and FSW hotspot as Primary Sampling Unit (PSU). Statistical analysis was performed in R (version 4.0.5) and the Bayesian Model Averaging (BMA) was used to produce final PSE with 95% credibility set (95% CS).

Results:

We sampled 1,766, 1,848, and 1,865 FSWs and sexually exploited minors for each capture round. There were 169 recaptures strictly between capture 1 and 2, 210 recaptures exclusively between capture 2 and 3, and 65 recaptures between capture 1 and 3 only. There were 61 FSWs captured in all three captures. The median PSE of street- and venue-based FSW and sexually exploited minors aged 15 and above in Rwanda is 37,647 (95% CS [31,873–43,354]) corresponding to 1.1% [0.9–1.3] of total adult females 15 years or older in the general population. Higher FSWs PSE was found in Western province, followed by Northern and Eastern province, then Kigali and Southern province were found to have relatively lower PSE respectively.

Conclusions:

This study provides, for the first time, both the national and provincial level size estimate of the street- and venue-based FSW population, aged 15 or older, in Rwanda. Comparing with the previous two rounds of FSWs PSEs at national level, we observed a larger increase of the street- and venue-based FSWs population size in Rwanda. The findings from this study, might have not considered FSWs with high profile including those who do not want anyone to know they are female sex workers due to several reasons, leading to a possible underestimation of the true PSE. This might be an opportunity for further research.