How did HIV start?

[072508]

Im sorry if im not posting in the correct area or if this is a dumb question.  Im new to the whole HIV thing and im just curious.

How did HIV start? I mean way back when the first case came about did two peoples fluids hate each other and started this out no where? Or possibly a man-made disease, i know, ridiculous, but this seems more realistic than this disease that just formed out of no where when at one point everything was fine till something disagreed and it came about...

Hopefully someone has some insight on this.

[J220]

A recent article on this topic is here:

http://www.abc.net.au/news/stories/2008/10/02/2379936.htm

In essence, the working hypothesis is that it was transferred from chimps to humans maybe over a 100 years ago. Perhaps a butcher was working on the carcass if an infected chimp, but and the blood somehow mixed with his, through a cut or something. At least this is the latest I remember reading about this.

[Miss Philicia]

And the animal predecessor of HIV may be much older than previously believed:

http://www.guardian.co.uk/science/2008/dec/02/hiv-aids-research

[AtomicA]

After two years of waffling, I finally decided on primatology as a major in school. My entire life is studying primates (was in Belize studying howlers this summer, heading to Ghana to study Colobus monkeys in the spring), so based on genetic evidence I can say the most agreed upon theory is that HIV is derived from the combination and mutation of at least two, possibly more, strains of SIV - the simian equivalent of HIV.

I'm sure everyone has heard of the organized collective hunting of colobus monkeys by chimps that Jane Goodall first observed, but further study has shown that depending on where the chimps live, they will hunt as many species of colobines as they can get their hands on. We're pretty sure that each species of colobus monkey has their own unique strain of SIV and from what we can tell, the consumption of multiple species, and thus multiple strains of SIV by chimps lead to a series of hybridizations and mutations in the chimp genome that eventually produced a nearly complete version of HIV inside chimps. Since people have had a really nasty habit of hunting our closest living relatives for thousands of years, it likely took just one unlucky bush meat hunter to give HIV to the entire human race.

when will people learn that there is no worse pet or food than a primate?

It also appears that SIV has been floating around in the old world primate populations for so many millions of years that most of them can harbor the virus without ever developing AIDS like symptoms. It's also one of the reasons why using chimps to study new HIV drugs is such a bad idea. Turns out chimp immune systems are far better equipped to deal with HIV as a result of a long history with SIV so drugs that seem to practically cure HIV in chimps often do next to nothing in humans.

just as an aside, HIV isn't likely to be the last nasty bug we catch by keeping and eating primates. Simian Foamy Virus (SFV) is a retroviral spumavirus that was recently discovered to be able to jump to humans. I forget which country (I think Cameroon?) but The US and WHO have done huge studies of farmers around large populations of captive and wild primates and found that about 1% of the human population was testing positive for the virus. Something like 80% of primates born in captivity are infected with it and it can be transmitted to humans through a simple bite. So far it's not been shown to cause any sort of disease symptoms, but as is the case with all insidious zoonosis, one or two simple mutations that would do nothing to the natural host can wreak havoc on humans.

moral of the story - never eat, feed or keep a primate as a pet!