HIV prevalence appears to be very low in Madagascar compared with other countries in sub-Saharan Africa. According to UNAIDS/WHO epidemiological model estimates,, the adult HIV prevalence rate in the country was 0.3 percent by the end of 2001 compared to 9 percent in sub-Saharan Africa and up to 25 percent in the adjacent countries in the Southern African region (UNAIDS, 2002). However, there are some important warning signs both that HIV prevalence may be higher than estimated, and that Madagascar is ripe for a rapid increase in HIV infections. Most important are the high prevalence of sexually transmitted infections (STI) that share modes of transmission and behavioral risk factors with HIV and the lack of knowledge on how to prevent infection, described further below. A recent study in Madagascar showed that 82 percent of female sex workers had at least one sexually transmitted infection (FHI/USAID, 2001), making Madagascar’s STI prevalence rate in excess of that in most high HIV prevalence countries. STIs are not just an indicator of risk behavior; they also directly make people biologically susceptible to HIV, and as reported by Cohen et al. (1996), thus are also associated with acquisition of HIV and higher rates of incidence and prevalence.