No evidence for transmission of SIVwrc from western red colobus monkeys (piliocolobus badius badius) to wild west african chimpanzees (pan troglodytes verus) despite high exposure through hunting

Blood and plasma samples from 32 wild chimpanzees were tested with INNO-LIA HIV I/II Score kit to detect cross-reactive antibodies to HIV antigens. Twenty-three of the samples were also tested for antibodies to 43 specific SIV and HIV lineages, including SIVwrc. Tissue samples from all but two chimpanzees were tested for SIV by PCRs using generic SIV primers that detect all known primate lentiviruses as well as primers designed to specifically detect SIVwrc. Seventeen of the chimpanzees showed varying degrees of cross-reactivity to the HIV specific antigens in the INNO-LIA test; however no sample had antibodies to SIV or HIV strain - and lineage specific antigens in the Luminex test. No SIV DNA was found in any of the samples.We could not detect any conclusive trace of SIV infection from the red colobus monkeys in the chimpanzees, despite high exposure to this virus through frequent hunting. The results of our study raise interesting questions regarding the host-parasite relationship of SIVwrc and wild chimpanzees in their natural habitat.Simian Immunodeficiency Viruses (SIVs) are the direct precursors of Human Immunodeficiency Viruses (HIVs) that have caused the HIV/AIDS pandemic in the human population [1,2]. Although the conditions and circumstances of cross-species transmission of SIVs from primates to humans remain unknown, human exposure to blood or other secretions of infected primates (chimpanzees, gorillas, sooty mangabeys) through hunting and butchering of primate bushmeat, represents the most plausible source for human infection [1-6]. Currently, serological evidence of SIV infection has been shown for more than 40 different primate species and SIV infection has been confirmed by sequence analysis in the majority of them. The routes of SIV transmission within and between host species are not fully known, however, sexual contact and biting within one species, and biting and blood-to-blood/mucosa contact (mainly observed in hunter - prey relationships) amon