Simon's group analyzed the blood of a Cameroonian woman who died of AIDS in 1995. Her strain of the virus was unique and fell halfway between HIV and SIV genetically. It was identical to an odd strain taken from a chimpanzee. However, little is known about the women, her family or history. It is not possible to say how she might have caught the virus from a chimpanzee.
Many scientists believe the virus spread to humans through infected ape or monkey meat.
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