HIV Transmission High Among Female Sex Workers

The incidence and transmission of HIV remains high in female sex workers (FSW) in Tanzania according to a study published in Frontiers in Reproductive Health.¹ Future interventions could help in reducing both the transmission and incidence in this population of patients.

There are approximately 39 million people in the world living with HIV as of 2022.² The incidence of HIV per year is 0.18% in adults aged 15 years and older in Tanzania; however this rate is higher in women at 0.24% compared with 0.11% in men. FSW are a population of particular concern when it comes to the high incidence rate, as FSWs bear a significant HIV burden in both Eastern and Southern Africa of up to 33.3%. HIV estimates for FSWs in Tanzani have been lacking. This study aimed to use a sample size within a real-life program that delivered HIV prevention interventions focusing on FSWs to offer insights into the HIV epidemic.

HIV transmission in female sex workers can be addressed with targeted interventions | Image credit: fizkes - stock.adobe.com

Data from the Sauti Project was used for this analysis. The Sauti Project is a United States President’s Emergency Plan for AIDS Relief funded and administered by the United States Agency for International Development. The project provides HIV prevention, treatment, and sexual and reproductive health care. The Project ran from October 2015 to January 2020.

This study used data regarding seroconversion and associated factors in FSWs from October 2016 to September 2018. Data also included clients of FSWs (CFSWs), men who have sex with men (MSM), adolescent girls, young women, children of FSWs, and those who lived in areas with a high risk of infection from HIV. FSWs aged 18 years and older made up the participants in this study. A project monitoring database was used to enter de-identified data, which included daily HIV testing. Patients were excluded if they had a positive follow-up HIV test within 4 weeks of an initial negative test or who had a first negative HIV test on or after April 2018. Patients were included if they had an initial negative HIV test and had at least 1 follow up test at a subsequent visit.

Age, education level, condom use, sexually transmitted infection (STI) screening results, and marital status were all collected. Seroconversion of HIV at least 4 weeks after the initial negative test result was the primary outcome of the study. Rapid diagnostic tests were used for this function.

There were 17,977 patients included in this study, of whom 68.2% were aged between 25 and 34 years, 45.7% had completed primary school, and 92.5% had tested negative for STIs. There were 38,037 additional tests that were performed after all participants had an initial test, which equaled 2.1 tests per FSW. Seroconversions occurred in 6.6% of the participants more than 1 month after the baseline test and the overall seroconversion rate was 8.6 per 100 person years. The median (IQR) follow-up time was 7.8 (4.4-13.4) months.

FSWs who were aged 35 years and older had a higher rate of seroconversion at 20.6 per 100 person years. This also applied to patients who were diagnosed with STIs (16.1 per 100 person years), and FSWs who did not report condom use in their last 3 occasions of intercourse (9.1 per 100 person years).

FSWs who were aged 35 years and older had a higher risk of seroconversion compared with FSWs aged 18 to 24 years (adjusted HR, 2.53; 95% CI, 2.03-3.14). Patients who reported not using a condom (adjusted HR 1.27; 95% CI, 1.13-1.42) had a higher risk of seroconversion compared with those who sometimes or always used a condom and patients who had secondary education had the lowest risk of seroconversion (adjusted HR, 0.51; 95% CI, 0.42-0.63) compared with those who did not complete school.

There were some limitations to this study. There could have been unmeasured confounding factors due to the retrospective data used. The results may not be applicable to all FSWs in Tanzania or other countries. Long-term trends may not have been collected due to the shorter timeframe.

The researchers concluded that targeted interventions for FSWs could help to reduce HIV transmission in this demographic. Expanding HIV prevention services to FSWs, including timely screening and treatment, could help in reducing the risk of HIV transmission in the future.

References

1. Mbita G, Mwanamsangu A, Komba AN, et al. HIV seroconversion among female sex workers: retrospective cohort study from a large-scale HIV prevention and sexual and reproductive health program in Tanzania. Front Reprod Health. 2024;6:1332236. doi:10.3389/frph.2024.1332236
2. The global impact of HIV & AIDS. HIV.gov. Updated November 15, 2023. Accessed July 2, 2024. https://www.hiv.gov/hiv-basics/overview/data-and-trends/global-statistics