Male commercial sex workers (CSWs) in northern Thailand are at high risk for HIV-1 infection and may be exposed to multiple subtypes of HIV-1 through sexual contact with men and women from Thailand, other Asian nations, and the West. We studied 103 male Thai nationals working in gay bars and clubs in Chiang Mai city who participated in the 1994 sentinel surveillance of the Thai Ministry of Public Health using HIV serologic testing, DNA polymerase chain reaction methods, molecular cloning, differential colony hybridization, nucleotide sequencing, and a third hypervariable region (V3) peptide enzyme-linked immunoabsorbent assay to differentiate subjects infected with HIV-1 subtypes B, E, both, or neither. The majority (58%) reported heterosexual orientation, and 35 (34%) were married. Seventeen (16.5%) were HIV infected: 16 (94%) of 17 had HIV-1 subtype E; 1 had HIV-1 subtype B. Two subjects had dually reactive results by molecular techniques but colony hybridization sequencing revealed only HIV-1 subtype E. HIV-1 subtype E appears to be the predominant clade among male CSWs in northern Thailand. This may have important implications for the global kinetics of the HIV epidemic.
PIP: Male prostitutes in northern Thailand are at high risk for HIV-1 infection and may be exposed to multiple subtypes of HIV-1 through sexual contact with men and women from Thailand and elsewhere. Blood samples of 103 male Thai nationals working in gay bars and clubs in Chiang Mai collected during the Thai Ministry of Public Health's 1994 sentinel surveillance were studied to determine the prevalences of HIV-1 subtypes B and E in the population. The men reported having an average of 2.5 male clients per week and had been in the business from 1 month to 7 years, with a median duration of 4 months. HIV serologic testing, DNA polymerase chain reaction methods, molecular cloning, differential colony hybridization, nucleotide sequencing, and a third hypervariable region (V3) peptide enzyme-linked immunoabsorbent assay were used to differentiate subjects infected with HIV-1 subtypes B, E, both, or neither. 58% of the men reported a heterosexual orientation outside of work and 34% were married. 72.1% reported inconsistent or no condom use with sex partners. 17 (16.5%) were infected with HIV. Of those infected, 16 (94%) had HIV-1 subtype E and 1 had subtype B.