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Prevalence of HIV, Sexually Transmitted Infections, and Risk Behaviours Among Female Sex Workers in Nairobi, Kenya: Results of a Respondent Driven Sampling Study


We conducted a respondent driven sampling survey to estimate HIV prevalence and risk behavior among female sex workers (FSWs) in Nairobi, Kenya. Women aged 18 years and older who reported selling sex to a man at least once in the past 3 months were eligible to participate. Consenting FSWs completed a behavioral questionnaire and were tested for HIV and sexually transmitted infections (STIs). Adjusted population-based prevalence and 95 % confidence intervals (CI) were estimated using RDS analysis tool. Factors significantly associated with HIV infection were assessed using log-binomial regression analysis. A total of 596 eligible participants were included in the analysis. Overall HIV prevalence was 29.5 % (95 % CI 24.7–34.9). Median age was 30 years (IQR 25–38 years); median duration of sex work was 12 years (IQR 8–17 years). The most frequent client-seeking venues were bars (76.6 %) and roadsides (29.3 %). The median number of clients per week was seven (IQR 4–18 clients). HIV testing was high with 86.6 % reported ever been tested for HIV and, of these, 63.1 % testing within the past 12 months. Of all women, 59.7 % perceived themselves at ‘great risk’ for HIV infection. Of HIV-positive women, 51.0 % were aware of their infection. In multivariable analysis, increasing age, inconsistent condom use with paying clients, and use of a male condom as a method of contraception were independently associated with unrecognized HIV infection. Prevalence among STIs was low, ranging from 0.9 % for syphilis, 1.1 % for gonorrhea, and 3.1 % for Chlamydia. The data suggest high prevalence of HIV among FSWs in Nairobi. Targeted and routine HIV and STI combination prevention strategies need to be scaled up or established to meet the needs of this population.

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The authors acknowledge Nyawira N Njeri, Soloman Kamuti, Gloria Gakii, George Rutherford from the University of California San Francisco, Mary Lou Lindegren from Vanderbilt University, and the study participants for their valuable contributions. The authors also wish to thank the National HIV and STI Control Programme (NASCOP), the National AIDS Control Council, the University of Manitoba’s Sex Worker Outreach Programme (SWOP), Liverpool VCT, the University of Nairobi Institute of Tropical and Infectious Diseases (UNITID) Laboratory, the Mombasa HIV/STD Research Laboratory, the University of Washington, the Gay and Lesbian Coalition of Kenya (GALCK), and the participants for their respective supportive roles in the successful completion of this research. This study was funded by the President’s Emergency Plan for AIDS Relief through The Centers for Disease Control and Prevention (CDC), through the Population Council’s cooperative agreement of Award No. 5U62PS224506.


The findings and conclusions in this paper are those of the authors and do not necessarily represent those of the US Centers for Disease Control and Prevention or the Government of Kenya.

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Correspondence to Helgar Musyoki.

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Musyoki, H., Kellogg, T.A., Geibel, S. et al. Prevalence of HIV, Sexually Transmitted Infections, and Risk Behaviours Among Female Sex Workers in Nairobi, Kenya: Results of a Respondent Driven Sampling Study. AIDS Behav 19, 46–58 (2015).

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  • Female sex worker
  • Kenya
  • HIV
  • Sexually transmitted infection
  • Respondent driven
  • Sampling