Background:  Men who have sex with men (MSM) account for a significant proportion of new HIV infections in the United States and appear to be driving a recent upswing in incident cases. Many MSM continue to meet their sexual partners at bathhouses. Few studies have described the population of bathhouse patrons and their frequency of bathhouse use.

Methods:  In 2006, Denver Public Health designed and implemented a survey of 296 patrons identified by staff inside of 3 bathhouses in Denver using self-administered questionnaires on handheld PDA. The survey included questions on sexual and drug using risk behaviors, HIV serostatus, frequency of use of the baths, and serostatus of sexual partners. Data are described proportionally.

Results:  Of the 296 patrons surveyed, 69% were single and 25% were in a relationship; 31% had some college education while 51% had a Bachelor’s degree or higher; 77% were gay, 22% bisexual or straight, and 21% were known to be HIV-infected; 83% reported that their first visit to a bathhouse was more that 6 months ago and 88% reported that their most recent visit before the survey day was in the last 6 months; 69% of men reported going to the baths >1 time a month. HIV⁺ patrons reported more unprotected insertive and receptive anal sex on the survey day:  23% and 21%, respectively, when compared to their negative counterparts, 8% and 4%, respectively; 37% of HIV-infected men ever had unprotected anal sex in a bath compared to only 14% of HIV^– men; 36% of HIV⁺ men stated that their most recent sex partner in a bathhouse was also HIV-infected, while 36% had a partner of unknown status. Only 3% of HIV^– men had ever had a positive partner in the baths, although 37% did not know the status of their last sex partner.

Conclusions:  Patrons of bathhouses reported frequent use of the facilities, not isolated events, with the majority attending the baths more than once a month. Persons who are HIV-infected reported more episodes of unprotected sex, and, though they reported more HIV-infected partners, were equally as likely as HIV-uninfected men to have sex with a partner whose HIV status is unknown. Bathhouses continue to be likely locations for HIV or sexually transmitted disease transmission to occur. More research is needed on who bathhouse patrons are and how sexual partners are selected in these venues.