Group sex events amongst non-gay drug users: an understudied risk environment.

This article discusses relevant literature on group sex events--defined as events at which some people have sex with more than one partner--as risk environments, with a particular focus on group sex events where people who take drugs by non-injection routes of administration participate and where the event is not primarily LGBT-identified, at a "classic" crack house, nor in a brothel. It also briefly presents some findings from a small ethnography of such events. Group sex participation by people who take drugs by non-injection routes of administration seems to be widespread. It involves both behavioural and network risk for HIV and STI infection, including documented high-risk behaviour and sexual mixing of STI- and HIV-infected people with those who are uninfected. Indeed several HIV and STI outbreaks have been documented as based on such group sex events. Further, group sex events often serve as potential bridge environments that may allow infections to pass from members of one high-risk-behavioural category to another, and to branch out through these people's sexual and/or injection networks to other members of the local community. The ethnographic data presented here suggest a serious possibility of "third party transmission" of infectious agents between people who do not have sex with each other. This can occur even when condoms are consistently used since condoms and sex toys are sometimes used with different people without being removed or cleaned, and since fingers and mouths come into contact with mucosal surfaces of other members of the same or opposite sex. In addition to being risk environments, many of these group sex events are venues where risk-reducing norms, activities and roles are present--which lays the basis for harm reduction interventions. Research in more geographical locations is needed so we can better understand risks associated with group sex events in which drug users participate--and, in particular, how both participants and others can intervene effectively to reduce the risks posed to participants and non-participants by these group sex events. Such interventions are needed and should be developed.