Reports of substantial rises in the incidence of HCV among MSM populations in the UK  (STI/Yaphe & Klein;  STI/Ghosn & Chaix) have attracted some attention in STI journal.  Not least because intravenous drug use is the most obvious mode of transmission for this blood-borne virus, and MSM have in the past tended not to use this route of administration.  The question then arises what specific factors in the environment of these MSM populations are increasing their risk?  The question is all the more urgent as – whatever those factors may be – MSM populations seem as yet largely incapable of reducing them – to judge by the large proportion of successfully treated MSM who become re-infected within two years (40% according to a N. London hospital). A number of recent contributions to STI journal consider the role of MSM sex in HCV transmission (STI/Stall & McFarland; STI/Valencia & Salas), and what it is in the practices or lifestyle of MSM that puts them at particular risk. Associations have been identified with number of partners, casual anal sex, sex parties (STI/Marcellin & Spire): specific practices such as fisting, rimming, recreational use of intra-nasal drugs (STIs/Turner & Stephenson): interactions between these practices and certain self-described MSM lifestyle groups such as “leather”, or “lycra & rubber” (STI/Matser & van der Loeff).

A recently published guide for health professionals (ChemSex & Hepatitis C), claiming to be based on c.500 conversations with MSM clients, offers an illuminating, ground-level account of one risk environment: events involving “ChemSex”, or the collective use of recreational drugs to enhance sexual experience. The authors claim that ChemSex parties are a growing HCV risk for MSM for three reasons: greater availability of certain non-injection drugs; increased injecting drug use; more widespread use of smartphone Apps and online “hooking-up” sites.  MSM involved in Chemsex, they claim, are a particularly hard-to-reach group for health professionals because of their use of informal private venues (rather than clubs, or the street), and a lack of exposure and openness to IDU service messages owing to a past preference among MSM for non-intravenous drugs.

Before health professionals can communicate effectively with these clients about the potentially stigma-laden issue of HCV they need to develop an awareness of the various elements of risk in the ChemSex environment.     The booklet aims to guide health professionals on this path. This it is does by means of an illustrative “case study”, as well as by a systematic itemization of potential risk factors in the ChemSex environment, including some less obvious transmission routes  – such as blood on douching tools or shower hoses, or blood on the lube pump, or snorting straw.   Language, of course, is at the heart of communication.  The booket, therefore, includes a handy list of current popular terms, as well as suggested  questions to ask at consultations.