Access to HIV testing for sex workers in Bangkok, Thailand: a high prevalence of HIV among street-based sex workers.

We offered voluntary counseling and testing (VCT) for HIV and syphilis to women attending three public sexually transmitted infection (STI) clinics in Bangkok, Thailand from May 2004 to June 2006. The testing was performed at either one of three STI clinics in Bangkok or at mobile VCT in the same area as the outreach activity. Six-hundred eighty-four women were tested. The HIV prevalences among the street-based sex workers, brothel-based sex workers and other women in these areas not reporting sex work who tested in the clinics were 45.8% (38/83), 4.2% (10/236) and 9.9% (28/284), respectively. The prevalences of syphilis in these groups were 13.3%, 2.1%, and 2.6%, respectively. Street-based sex work and longer duration of sex work were independent risk factors for HIV in-fection (p < 0.001 and p = 0.02, respectively). HIV and syphilis prevalences were 21.0% and 3.7% among 81 street-based sex workers accepting mobile VCT, The street-based sex workers in Bangkok had substantially higher HIV and syphilis prevalences than other sex workers. Street-based sex workers should be sampled during routine surveillance to obtain systematic information on disease preva-lence and risk behaviors in this group.