Disconnects in presumed heterosexual HIV transmission in Malawi

Obtaining large-scale sexual network data is difficult [1] and doing so in a poor country is especially difficult. We congratulate Helleringer and Kohler [2] on their pioneering study of a sexual network on Likoma Island, Malawi. Their approach represents an important step toward appropriate research designs for elucidating HIV transmission dynamics in sub-Saharan Africa. Despite this achievement, their results undermine their assertion that the Likoma sexual network sustains epidemic HIV transmission. In fact, their findings add to the already considerable evidence against penile--vaginal intercourse as the primary driver of HIV transmission in sub-Saharan Africa [3].