The epidemiology of HIV infection among male commercial sex workers in northern Thailand.

Abstract

A public health official questions the conclusion of investigators of an epidemiologic study of HIV infection among male commercial sex workers (CSWs) in Chiang Mai Thailand. Their conclusion was that since most CSWs report to be heterosexual male CSWs are a crucial epidemiologic link in the spread of HIV. The official suggests that the spread of HIV among male CSWs is a by-product of the heterosexual epidemic in Thailand. The increase of HIV from 1.4% in 1989 to 13.6% in 1990 among male CSWs corresponds to the increase of HIV prevalence among military recruits in northern Thailand (3-11%). Sexual activity with a female CSW was the most significant risk factor among military recruits. Male CSWs often have heterosexual intercourse outside of male prostitution. In the epidemiologic study longer duration of work as a CSW provided significant protection against HIV seroconversion suggesting that HIV prevalence among clients is likely low and individual heterosexual contacts are the mode of HIV infection. About 40% of the male CSWs had worked as CSWs for less than two months which is scarcely sufficient time to develop detectable HIV antibodies. This suggests that they were already HIV seropositive when they began working as CSWs. It would be interesting if the investigators could demonstrate the HIV prevalence rate by duration of work to determine the probability of HIV acquisition elsewhere and HIV prevalence rate by home province. If men from provinces where the prevalence rates among female CSWs are high tend to be HIV positive this may also indicate acquisition of HIV infection outside male prostitution.