SIV Very Rare in Wild Chimps

According to a report in the 18 January 2002 issue of the international journal, Science, simian immunodeficiency virus (SIV) appears to be very rare among wild chimpanzees, and a single case discovered in Tanzania is considerably different from several HIV strains--suggesting it was not a source for the human epidemic.

After testing 58 wild chimpanzees in west, central and eastern Africa, Mario L. Santiago of the University of Alabama at Birmingham and colleagues found only one SIV-positive male chimp at Gombe National Park, among a population made famous by Jane Goodall. Clearly, the prevalence of SIV among wild chimps is "surprisingly low," and may mean that the virus isn't easily transmitted among the animals, the researchers suggested.

Until now, all identified SIV strains have been found only in captive chimps of the subspecies Pan troglodytes troglodytes. The new study reports on a case in the subspecies Pan troglodytes schweinfurthii. Analyzing fecal and urine samples, instead of blood, allowed the scientists to search for SIV noninvasively, and sets the stage for further investigations of viral evolution.

-- Becky Ham