HIV-Related Viruses Still Cross Species

Article excerpt

Scientists generally agree that simian viruses resembling the human immunodeficiency virus (HIV), which causes AIDS, originally spread from chimpanzees and sooty mangabeys to people in central Africa (SN: 2/6/99, p. 84). Researchers now have hard evidence that other variations of simian immunodeficiency virus (SIV) occur in wild nonhuman primates and continue to cross into people in Africa.

Although captive primates have shown SIV infections, scientists wanted to investigate the virus prevalence in the wild. They collected blood samples from 384 wild-born baboons and monkeys in Cameroon--17 species altogether.

Only chimpanzees in west central Africa harbor a viral strain that's "truly closely related" to the most lethal AIDS strain, but other primates bear watching as viral reservoirs, says Beatrice H. Hahn of the University of Alabama in Birmingham. The blood samples revealed that 18 percent of the animals harbored SIV antibodies that bind strongly to HIV proteins. That finding indicates that some SIV strains in animals today, while not lethal to people, have clear similarities to HIV, says Hahn's colleague Eric Delaporte of the Institute for Research and Development in Montpellier, France.

Another 14 percent of the animals had antibodies that bind less strongly to HIV proteins in this cross-species test, says Delaporte. Several of the SIV subtypes identified were previously unknown, he said at the Eighth Annual Retrovirus Conference in Chicago this week. …