“…These include female sex workers (Page-Shafer et al, 2005); prisoners (Moser et al, 2004); intravenous drug users (Meyers et al, 1995); the homeless (Nyamathi et al, 2004); and men that have sex with men (Sherr, Bolding, & Elford, 2004). In many resource-limited settings, such populations are often marginalised within the broader community and considered vulnerable both in terms of increased risk of HIV and sexually transmitted infections (STIs), and due to stigma, poverty, social exclusion and lack of access to education, health care and other essential services (Gysels, Pool, & Nnalusiba, 2002;Mills et al, 2006).…”