Virus, immunodeficiency monkey (SIV) virus, are at least 45 species of primates African with.

virus, SIV, in fact, the agent is coming to the HIV virus be is that the two types of HIV-1 and HIV-2 split. It seems that both HIV-1 and HIV-2 in principle, it belongs to primates the center of Africa, has been in the early Twenty-First Century to the human body have been transferred. HIV-1 originally belonged to the southern regions of Cameroon and has evolved immunodeficiency virus monkey that among chimps, the wild outbreak.. Also, the virus HIV-2 evolved virus SIV, among species, monkeys to name smoked, which is in West Africa (from southern Senegal to western Ivory Coast) life. Beveled like the monkey night compared to HIV-1 are resistant, and this is probably due to a type of gene, linkage of two species of resistant virus in it.

evidence that is available suggests that in the hunting or sale of animal involvement, had suffered from the virus, SIV. Although the SIV virus is weak that the defense system of the human body, deal with it and makes more than a few weeks in the human body does not remain, but the transfer is fast and consecutive, It, human, different enough time to the virus to convert it to HIV. In addition, due to the low rate of transmission person-to-person disease, SIV can only through a large number people at risk out that it is believed that before the twentieth century, such a demographic existed.