There exist several types of HIV viruses. The major type of HIV that has become the scourge of the world is the HIV-1 M group.  HIV-1 originated from its equivalent in chimpanzees, SIVcpz (simian immunodeficiency virus in chimpanzees).  Indeed, the most diverse forms of HIV-1 are found in the range of chimpanzees in west equatorial Africa.(1-4)  Similarly, HIV-2 is most closely related to SIV in sooty mangabey monkeys and its most diverse forms are found in regions that overlap with the range of these monkeys.(5-10)  The common ancestor of the different HIV-1 M types dates to 1931 (95% CI = 1915-1941.).(5, 11)  SIV transfer from chimpanzees and sooty mangabey monkeys to humans has been documented on at least 7 occasions, and laboratory experiments have revealed the ease with which various SIV strains can infect and replicate within some cells in human blood.(12)

SIV strains in two monkey species [ that are butchered and eaten by chimpanzees] hybridized to form SIVcpz.(13)  SIV viruses have mutated into HIV viruses, and their transfer to humans is almost certainly a result of the sub-Saharan African practice of butchering and eating chimpanzees, gorillas, and monkeys (bushmeat).(13-15)  The alternative hypothesis that HIV originated from SIV as a result of the use of contaminated oral polio vaccine in 1950s Central Africa is highly implausible and does not have a shred of evidence in its support.(5, 11, 16-18)  Additionally, HIV-infection has been documented in sub-Saharan Africa in 1959.(19, 20)  An analysis of 1,099 Central African bushmeat hunters revealed that 1% of them were infected with the simian foamy virus (SFV), which is a retrovirus like SIV and HIV.  The investigators demonstrated three geographically-independent human SFV infections, all acquired from different monkey and ape species: De Brazza's guenon, mandrills, and gorillas. The De Brazza's guenon and mandrill are naturally infected with SFV.  Clearly, more AIDS-like viruses are forthcoming for humanity.

In the First-World, AIDS was first diagnosed among American white homosexual men in the early 1980s, but retrospective studies have documented HIV and AIDS among Haitian immigrants to the U.S. and Americans associated with them in the late 1970s.(21)  Similarly, body fluids obtained from a Norwegian family between 1971 to 1976 revealed a type of HIV-1 infection, acquired earlier than 1971, and this type of HIV is mainly restricted to West Africa.(20)  HIV appears to have entered the U.S. around the late 1960s,(21) and was then primarily spread by homosexuals throughout the U.S. and Europe.  In a survey on AIDS conducted in Belgium, Denmark, Finland, France, Germany (FDR), Italy, the Netherlands, Norway, Sweden, Switzerland, and the U.K, in 1983, the most important contributors to the AIDS epidemic in Europe were male homosexuals (58% of all cases, and likely contracted from the U.S.A., Europe, and Haiti), followed by individuals from Central Africa (26%), and whites who had sex with natives from Central Africa (3%); drug abuse was not a risk factor.(22)


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