SIV 'very rare' in wild chimps
Mario L. Santiago and colleagues tested 58 wild chimpanzees in west, central and eastern Africa and found only one case of the virus. This was considerably different from several HIV strains, suggesting it was not a source for the human epidemic.
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.
Reference: Science 295, 465 (2002)