Most people now know that HIV is thought to have been spread to humans from chimpanzees. The natural and widespread reaction to this news was, “Why are people having sex with monkeys?!” As a scientist and one who has faith in the limits of human depravity (somehow bestiality seems even worse to me if it’s with a monkey), I felt there must be some other explanation for this. Turns out there is.
Image credit: Chimpanzees, via http://www.bbc.co.uk
Because no one has ever found who was the first person to show HIV symptoms, we don’t know exactly what year or what place it first showed up. The main theory is linked to experiments performed on chimpanzees in 1957 where chimp kidneys were used to manufacture polio vaccines. If one of those monkeys was infected, that would certainly do the trick. This theory is just the best possible explanation but is still not completely accepted. Another consideration is that HIV has only been a major problem in the 20th century, but people have been hunting chimps for much longer than that (and probably exposing themselves to monkey blood which would transfer the virus), so what’s with the delayed reaction?
Turns out chimps may not have been the original culprit! There could still be some HIV monster out there that really started all the trouble by giving it to chimps who then gave it to us. Darn you, HIV monster.
Okay But Why 