WASHINGTON, DC-For the first time, researchers have found a rare strain of simian AIDS in a wild chimpanzee. The discovery comes from advanced testing in Tanzania-several thousand miles east from the estimated birthplace of the disease.

Researchers were surprised not only by the discovery, but also by the location. The chimp in Tanzania could not carry the source of the current AIDS virus in humans because the strain is too different genetically. However, the monkey is the first reported case of simian AIDS found in the wild. Previous monkeys have tested positive, but only those in a captive environment. 

The report, published in a recent issue of the journal 

, was conducted by Beatrice Hahn, PhD, of the University of Alabama at Birmingham. Hahn and her research team worked with primatologists to identify different primates in the Tanzanian jungle. They matched these monkeys to fecal samples, which they tested with a new innovation. The fecal matter was tested for antibodies against SIV-simian HIV. The genetic material from fecal samples was used to determine if the animals had been infected with the virus. 

The lone chimpanzee that tested positive was a healthy 23-year-old male in Jane Goodall's colony. The monkey, while infected, was not carrying a virulent strain. None of his sexual partners became infected with the virus. 

The chimp's strain was also remarkably different from the strain thought to cause AIDS. This strain is more HIV-like and is found in captive animals in west-central African countries like Gabon and Cameroon. 