RESUMEN
OBJECTIVES: (1) To assess risk factors for urethral infections with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis among male clients of female sex workers (FSWs) in Benin; (2) to study the validity of LED testing of male urine samples compared to a highly sensitive gold standard (PCR) for the diagnosis of urethral infections with the organisms cited above. METHODS: Male clients of FSWs (n=404) were recruited on site at prostitution venues in Cotonou, Benin, between 28 May and 18 August 1998. A urine sample was obtained from each participant just before he visited the FSW, and tested immediately using a leucocyte esterase dipstick (LED) test. It was then tested for HIV using the Calypte EIA with western blot confirmation, and for C. trachomatis, N. gonorrhoeae, and T. vaginalis by PCR. After leaving the FSW's room, participants were interviewed about demographics, sexual behaviour, STI history and current symptoms and signs, and were examined for urethral discharge, genital ulcers, and inguinal lymphadenopathies. RESULTS: STI prevalences were: C. trachomatis, 2.7%; N. gonorrhoeae, 5.4%; either chlamydia or gonorrhoea 7.7%; T. vaginalis 2.7%; HIV, 8.4%. Lack of condom use with FSWs and a history of STI were independently associated with C. trachomatis and/or N. gonorrhoeae infection. Over 80% of these infections were in asymptomatic subjects. The overall sensitivity, specificity, positive and negative predictive values of the LED test for detection of either C. trachomatis or N. gonorrhoeae were 48.4%, 94.9%, 44.1%, and 95.7%, respectively. In symptomatic participants (n=22), all these parameters were 100% while they were 47.4%, 94.7%, 37.5%, and 96.4% in asymptomatic men (n=304). CONCLUSIONS: Since most STIs are asymptomatic in this population, case finding programmes for gonorrhoea and chlamydia could be useful. The performance characteristics of the LED test in this study suggest that it could be useful to detect asymptomatic infection by either C. trachomatis or N. gonorrhoeae in high risk men.
Asunto(s)
Hidrolasas de Éster Carboxílico , Trabajo Sexual/estadística & datos numéricos , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades Uretrales/diagnóstico , Adolescente , Adulto , Benin/epidemiología , Femenino , Humanos , Masculino , Tamizaje Masivo/normas , Persona de Mediana Edad , Análisis Multivariante , Juego de Reactivos para Diagnóstico/normas , Factores de Riesgo , Enfermedades de Transmisión Sexual/transmisiónRESUMEN
OBJECTIVES: Male clients of female sex workers have rarely been specific targets for HIV/sexually transmitted diseases (STD) interventions in sub-Saharan Africa. We assessed the effectiveness of outreach methodology for contacting sexual partners of female sex workers for purposes of HIV/STD prevention in Cotonou, Benin. DESIGN AND METHODS: In collaboration with owners/managers, outreach personnel and female sex workers, 404 clients were recruited on-site at prostitution venues, and provided urine samples for leukocyte esterase dipstick (LED), STD and HIV testing before having sex with female sex workers. After having sex they underwent an interview and physical examination. No payment was made for study participation. Prostitution site personnel (n = 41) and boyfriends of female sex workers (n = 56) were also recruited. RESULTS: In all 68% of the clients approached agreed to participate. On-site LED testing and free STD treatment were important factors in participation. HIV-1 prevalence was several-fold higher than in the general population in Cotonou, at 8.4, 12.2 and 16.1% in clients, personnel and boyfriends respectively, and was associated with increasing age and lack of condom use with female sex workers. Condom use rates by clients with female sex workers were non-negligible but sub-optimal, and low with regular partners. Approximately one-third of clients with regular partners also had other non-female sex worker sex partners. Boyfriends of female sex workers are of particular concern due to high numbers of partners, very low condom use rates and high HIV prevalence. CONCLUSIONS: Study findings indicate that male sex partners of female sex workers form a 'bridging population' for HIV/STD transmission both to female sex workers, as well as from female sex workers to the general population of women, particularly regular female partners.