New Virus May Have Come From Monkeys, Experts Say

Two new retroviruses never before seen in humans have turned up among people who regularly hunt monkeys in Cameroon, researchers reported on Friday. Like the AIDS virus, these viruses insert their genetic material directly into cells and perhaps even into a person's or animal's chromosomes. Closely related versions of the viruses cause leukemia, inflammatory and neurological diseases. The two new viruses are called human T-lymphotropic virus types 3 and 4 or HTLV-3 and HTLV-4. They are closely related to two known viruses called HTLV-1 and HTLV-2, which experts believe were transmitted to people, like HIV, from monkeys and apes.