South Africa has the largest number of people living with HIV in the world with over 5.5 million people infected with the virus (Shisana et al., 2005). However, heterogeneity in HIV prevalence among sub-groups within the South African population (Shaikh et al., 2006) indicates that certain groups of people are  more vulnerable to HIV infection than others.

Low- and middle-income countries (LMICs) often face scarcity of resources and high disease burdens. Research has identified effective and affordable interventions for many of the health problems in these countries (WHO, 2002). Decisions made on the basis of research evidence may not be only cost saving  (Garner et al., 1998) but also life saving (Volmink et al., 2004). Often, however, effective interventions are not translated into national policy or are not implemented.