Posted on 05/25/2006 2:14:18 PM PDT by blam
HIV origin 'found in wild chimps'
This mother chimp is SIV positive
The origin of HIV has been found in wild chimpanzees living in southern Cameroon, researchers report. A virus called SIVcpz (Simian Immunodeficiency Virus from chimps) was thought to be the source, but had only been found in a few captive animals.
Now, an international team of scientists has identified a natural reservoir of SIVcpz in animals living in the wild.
The findings are to be published in Science magazine.
It is thought that people hunting chimpanzees first contracted the virus - and that cases were first seen in Kinshasa, in the Democratic Republic of Congo - the nearest urban area - in 1930.
Scientists believe the rareness of cases - and the fact that symptoms of Aids differ significantly between individuals - explains why it was another 50 years before the virus was named.
This team of researchers, including experts from the universities of Nottingham, Montpellier and Alabama, have been working for a decade to identify the source of HIV.
While SIVcpz was only identified in captive animals, the possibility remained that yet another species could be the natural reservoir of both HIV and SIVcpz.
Gene tests
It had only been possible to detect SIVcpz using blood test - which meant that only captive animals could be studied.
This study, carried out alongside experts from the Project Prevention du Sida au Cameroun (PRESICA) in Cameroon, involved analysing chimpanzee faeces, collected from the forest floor in remote jungle areas.
The researchers went into the jungles of Cameroon
This was useful because University of Alabama researchers had been able to determine the genetic sequences of the chimpanzee viruses - which could then be searched for in the faecal samples.
Lab tests detected SIVcpz specific antibodies and genetic information linked to the virus in up to 35% of chimpanzees in some groups.
All of the data was then sent to the University of Nottingham for analysis, which revealed the extremely close genetic relationship between some of the samples and strains of HIV.
Chimpanzees in south-east Cameroon were found to have the viruses most similar to the form of HIV that has spread throughout the world.
The researchers say that, as well as solving the mystery about the origin of the virus, the findings open up avenues for future research.
But SIVcpz has not been found to cause any Aids-like illnesses in chimpanzees, so researchers are investigating why the animals do not suffer any symptoms, when humans - who are so genetically similar - do.
Close relation
Paul Sharp, professor of genetics at the University of Nottingham said: "It is likely that the jump between chimps and humans occurred in south-east Cameroon - and that virus then spread across the world.
"When you consider that HIV probably originated more than 75 years ago, it is most unlikely that there are any viruses out there that will prove to be more closely related to the human virus."
He said the team were currently working to understand the genetic differences between SIVcpz and HIV evolved as a response to the species jump.
Keith Alcorn of Aidsmap said: "The researchers have pinned down a very specific location where they believe the precursor of HIV came from.
"But there are vast areas of west Africa where other forms of SIVcpz lineages exist, and the possibility remains for human infection.
Yusef Azad, policy director of the National Aids Trust said: "This research is interesting as all discoveries which relate to the history and origins of HIV could be of value to the vital work being carried out by scientists in developing a HIV vaccine."
It was probably someone butchering a chimp that nicked themselves with a knife and absorbed blood through the cut.
When was Clinton over there? :o)
HIV is the virus itself. HIV = Human Immunodeficiency Virus.
AIDS is the disease caused by the virus. AIDS = Acquired Immunodeficiency Syndrome.
In short, the HIV causes AIDS by gradually killing off the immune system. When you say someone "has HIV" that means that they have contracted the virus. When you say someone "has AIDS" that means that they are showing symptoms of immune system deficiency.
The reason why someone can have HIV but not yet have AIDS is simply because they have the virus (HIV) but it hasn't yet killed off enough of their immune system for them to show symptoms of immune deficiency (AIDS).
As for the chimps, they have a closely related virus called SIV, which means Simian Immunodeficiency Virus. It's correct that the chimps do not develop SAIDS (the chimp version of AIDS) from the SIV that is endemic to their species.
Generally speaking, different apes and monkeys have slightly different strains of SIV and they are adapted to the version endemic to their species, so it doesn't kill them. However, when primates contract a version that is not endemic to their species, they do typically get SAIDS and die.
What this basically means is that SIV has been around long enough that monkeys and apes that carry versions of it have developed resistance. By contrast, HIV is so new that very few humans appear to be resistant, though contrary to popular opinion some people are clearly resistant to infection by HIV, while others are clearly resistant to developing AIDS even if they contract HIV.
In other words, if enough time passed and HIV was not controlled or eliminated then presumably humans in general would adapt to it just like the apes and monkeys have adapted to SIV, and then HIV would not bother us anymore. However, this will require hundreds, if not thousands, of years of evolution before it happened.
chop the raw liver out of a chimp, grow smallpox vaccine on it, filter it, and squirt it into the mouths of millions of black Africans wanting to be immune from smallpox. Some of them are going to have cancer sores on their gums...
...That's Canker sores on their gums...
That thread of yours is where I got the idea I read all of your posts that I see Bill
thanks
Again with the monkeys!?
I used to think they were cute until I read what the Jungle Book had to say about them. I LMAO!
Mark
My first guess would be while butchering them, or eating improperly cooked meat.
Mark
I thought that HIV is the virus, while AIDS is the manifestation of symptoms. But I could be wrong. It happened once before.
Mark
So Cheetah was Patient Zero.
I guess what happens in Cameroon doesn't stay in Cameroon.
True enough. Not having much butchering experience (well, except of mice), I'd forgotten that there will be the inevitable misses with the blade!
Did it come from someone that was confused thinking see monkey, do monkey instead of monkey see, monkey do.
I always suspected that, but I thought even homosexual perverts would not be that gross.
But then again........
Patient Zero or SV-40 contaminated vaccines?
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