A randomized, placebo-controlled trial of monthly azithromycin prophylaxisto prevent sexually transmitted infections and HIV-1 in Kenyan sex workers: study design and baseline findings

Our objectives were to describe the baseline findings of a trial of antibio tic prophylaxis to prevent sexually transmitted infections (STIs) and HIV-1 in a cohort of Nairobi female sex workers (FSWs). A questionnaire was admi nistered and a medical examination was performed. HIV-negative women were r andomly assigned to either one gram azithromycin or placebo monthly. Mean a ge of the 318 women was 32 years, mean duration of sex work 7 years and mea n number of clients was 4 per day. High-risk behaviour was frequent: 14% pr actised anal intercourse, 23% sex during menses, and 3% used intravenous dr ugs. While 20% reported condom use with all clients, 37% never use condoms. However, STI prevalence was relatively low: HIV-1 27%, bacterial vaginosis 46%, Trichomonas vaginalis 13%, Neisseria gonorrhoeae 8%, Chlamydia tracho matis 7%, syphilis 6% and cervical intraepithelial neoplasia (CIN) 3%. It a ppears feasible to access a population of high-risk FSWs in Nairobi with pr evention programmes, including a proposed trial of HIV prevention through S TI chemoprophylaxis.