Transferability of HIV by arthropods supports the hypothesis about transmission of the virus from apes to man.

The primate Pan troglodytes troglodytes, a chimpanzee subspecies, has recently been defined as a natural animal host of the human immunodeficiency virus (HIV). Apes are traditionally hunted in Africa and are offered for sale in open-air meat markets. The bloody carcasses are regularly covered with blood-feeding flies, amongst them possibly the stable fly (Stomoxvs calcitrans L.). a cosmopolitically occurring biting fly. This fly is the effective vector for the retrovirus causing equine infectious anemia [corrected]. According to laboratory experiments, the infectivity of ingested HIV is not reduced in the regurgitates of this fly. These findings are combined to explain the mechanism for a possible primary transmission of HIV from ape to man.