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Aids Virus Linked To Chimps

February 09, 1999

Scientists have traced the origin of the HIV virus to a certain subspecies of chimps. And that might help them find a vaccine to fight the AIDS-causing virus.

Many scientists have suggested that the virus was passed to humans from animals, but there was no genetic proof that chimps were the source. But thanks to a chimp named Marilyn, scientists say they now have their proof.

Marilyn was a research animal from Africa. The chimp, who died in '85, tested positive for a form of HIV. However, no techniques at the time could isolate the virus, so parts of her body were frozen. A decade later, Dr. Beatrice Hahn got hold of the parts. She led the team of scientists who are now saying chimps are the origin of the virus. And in her research, she found that Marilyn's virus was much like strains found in other chimps in Marilyn's subspecies. They were also similar to HIV-1, the most common strain of the virus that affects humans. HIV-1 is thought to have originated in the same region of Central Africa where Marilyn's monkey group is from. Additional tests convinced Hahn and her group that humans living in the same Central Africa region as Marilyn's subspecies got HIV-1 from the chimps.

It's still a mystery how the virus jumped from chimp to humans. Hahn suggests that humans were infected while hunting chimps for food.

The finding of the AIDS origin gives researchers a lot of hope. Says Steven Wolinsky, an AIDS researcher at Northwestern University Medical School: "If we know where we've been, we can tell where we're going."