HIV This Week

Keele BF, Van Heuverswyn F, et al. Chimpanzee reservoirs of pandemic and nonpandemic HIV-1. Science 2006 May 25[Epub ahead of print]. http://www.sciencemag.org/cgi/rapidpdf/1126531v1.pdf

HIV type 1, the cause of human AIDS, represents a zoonotic infection of staggering proportions and social impact. Yet, uncertainty persists regarding its natural reservoir. The virus most closely related to HIV-1 is a simian immunodeficiency virus (SIV) thus far identified only in captive members of the chimpanzee subspecies Pan troglodytes troglodytes. In this paper, Keele and colleagues report the detection of SIVcpz antibodies and nucleic acids in faecal samples from wild-living Pan troglodytes troglodytes apes in southern Cameroon where prevalence rates in some ape communities reached 29-35%. By sequence analysis of endemic SIVcpz strains, the authors could trace the origins of pandemic (group M) and non-pandemic (group N) HIV-1 to distinct, geographically isolated chimpanzee communities. The authors conclude that these findings establish Pan troglodytes troglodytes as the natural reservoir of HIV-1.