Malaria and HIV: a silent alliance.

HIV and malaria are leading causes of morbidity in sub-Saharan Africa. Recently, Abu-Raddad and colleagues explored the synergy between these diseases through a mathematical model that included all documented interactions. It emerges from the model parameter inputs that concomitant infection of both HIV and malaria fuels the spread of both diseases. For the first time, it is shown that, according to the model, transient but repeatedly elevated HIV viral loads due to recurrent co-infections, such as malaria, can also influence and increase HIV prevalence. Probably, these results are conservative and the true impact of the interaction could be even more important.