Behaviourally bisexual men as a bridge population for HIV and sexually transmitted infections? Evidence from a national probability survey.

We consider the potential of behaviourally bisexual men (BBM) as a bridge population in sexually transmitted infection (STI)/HIV transmission by comparing sexual risk behaviours, attitudes and sexual health outcomes of BBM (defined as men who reported sex with men and women), with men who reported (i) exclusively male partners (MEMP) and (ii) exclusively female partners (MEFP), using a probability survey of the British general population aged 16-44 years, conducted between 1999 and 2001 (n = 5168 men). About 1.3% of men who reported sex in the past five years were BBM (44.1% of all men reporting male partners); 29.0% of BBM were married/cohabiting with women. Median partner numbers in this timeframe were seven among BBM, two among MEFP and 10 among MEMP. Similar proportions of BBM and MEMP reported STI diagnosis/es in the past five years, yet BBM were less likely than MEMP to report HIV-testing (odds ratio adjusted for sociodemographics: 0.31). BBM are thus mid-way between MEFP and MEMP in their sexual risk behaviour, but are similar to MEMP in reporting STI diagnosis/es. These data have implications for health promotion and partner notification, as BBM are unlikely to be appropriately targeted by safe-sex messages aimed at men identifying as gay.