Origins Of HIV and Strains of HIV -- Questions & Answers
How did HIV start?
We don't know for sure but we can make good guesses. Currently medicine has declared two types of HIV virus. Called HIV-1 and HIV-2. In addition there is a similar virus that affects the monkey family (called simians), it was called SIV (Simian Immunodeficiency Virus)
This in itself is controversial due to the fact some strains of HIV-1 are genetically closer to SIV than to HIV-2. Also some strains of HIV-2 are closer to SIV than HIV-1.
In fact SIV was originally called HIV-2. After newspapers reported that Africans got AIDS from having sex with monkeys the medical community changed the name to SIV, the "S" of course standing for simian.
This is an example of politics interfering with proper medicine. You don't call rabies something else if it's in a dog. No rabies is rabies whether it's in a dog or human.
So when you read other website remember this. If HIV-1 and HIV-2 are both closer to SIV than they are to each other than SIV must be a form of HIV or vise versa.
But it's all just names so let's start with the premise HIV came from SIV and SIV lived in monkeys, particularly the green monkey. It is thought, through tracing the genetic make up of SIV, that different forms of the virus came in contact with each other and eventually caused a form of SIV that could be transmitted to chimpanzees.
Today HIV-1 has three major sub groups called "M," "N," and "O." It is thought each of these subgroups is from a time when the SIV crossed over from chimps to humans. So genetically it looks like SIV crossed over three times to humans and became HIV-1 (subgroup M) HIV-1 (subgroup N) and HIV-1 (subgroup O). You must also note each of the subgroups "M," "N," and "O," have additional divisions within themselves as well.
How is it possible for a virus to crossover species?
Usually viruses are very specific for not only a certain species but also certain cell in that species. However there are many times when viruses can cross over. For instance the flu viruses are thought to originate with birds, particularly chickens. In Southeast Asia and China chickens and humans live in cramped quarters and this gives opportunities for the virus to try and try to crossover till it gets it right.
When a virus crosses the species barrier it is called zoonosis.
How does it physically get from chimp to human?
The chief way would be by eating. For a long time it was thought chimps didn't eat meat or if they did they only scavenged. It was eventually observed chimps routinely hunt monkeys and eat them. In Africa it is quite common for hunters to kill and eat monkeys and chimps.
Any other way it could get from chimp to human?
Some people have made a cause for the polio vaccine or the smallpox vaccine given in the 1970s, in Africa, was contaminated. Indeed smallpox was wiped out in the 1970s the last place of natural occurrence was in Africa.
Because of the many subtypes it is thought, even in the vaccines were somehow contaminated it would only account for one of the subgroups, most likely the "M" subgroup.
Any other way?
From 1950 onward with the end of colonialism many newly independent African nations used "labor camps" to force a growth in agriculture. Forcing many people into unsanitary camps in jungles, to clear out the jungle, for farmland. This could have caused or at least contributed to the spread of SIV from chimps to humans.
What about conspiracy theories?
There are many out there, from the CIA to the KGB they've all been blamed. Since the Cold War was in large part fought by smaller proxy wars in Africa it gets attention.
There are also theories, which say the CIA manufacured HIV to kill off Africans or gay people, and it got out of hand. With gay men participating a trail vaccine of hepatitis-B, while Africans were getting vaccinated with smallpox, it makes the theory seem plausible to those who want to believe.
However it fails to account for the fact we do have a known case going back to 1959 so at best the CIA or KGB could've done was to release the virus 20 years later. The genetic engineering to create HIV from scratch didn't exist in 1959.
What about HIV-2
This is a somewhat "milder" form of HIV; it is thought to have crossed over not from chimps but from monkeys called Sooty Mangabeys. HIV-2 is less transmissible and is confined to West Africa for the most part.
So you're saying HIV definitely came from Africa?
Well you can't know for certain but is almost certain. SIV has never been seen in any of the primates from North America, South America or Asia.
Ironically there was a form of Ebola that was found in monkeys from the Philippines that devastated the monkeys but had no effect in humans.
Genetic tracing of HIV-1 always has led back to a strain of the SIV virus.
Well why did AIDS start suddenly?
The airplane probably did a lot to help it. Before the early 1980s flying was a rich man's way to travel. Wars in Africa, particularly in the Portuguese colonies caused mass movements of people. For instance the war in Angola was largely fought by Cuban troops, who could have taken the virus back to North America.
Who was patient Zero?
His name was Gaetan Dugas, and he was a Canadian flight attendant. He was also a gay male. He was first blamed for being a "mass spreader" that took the virus from Africa to Europe to the Caribbean and finally the United States. It was later revealed that the blood samples used were contaminated all the work was thoroughly discredited.
Gaetan Dugas died from AIDS but his being "spreader of AIDS" fell into myth, ironically being spread by the gay community.
So the airplane caused AIDS?
No it didn't cause it, but it enabled it to spread fast. You will find in any viral history all a virus needs is a chance to take off and it will. For instance, in the "Black Death," that nearly wiped out a third of Europe, it was always the port cities that got hit first and hit hard. So an efficient means of travel equals the ability to spread.
You will note in those days the monks and nuns lived cloistered away from the populations and they didn't get sick with things like "the plague" as often. At the time was seen as being in God's favour. In reality it was just they were far removed from the port cities.
Is that the only theory of how AIDS spread?
The blood industry didn't help either. By the late 1960s blood was starting to be transfused more and more into patients. Donors were actively sought.
In fact All In The Family did an episode where Archie is a blood donor to encourage people to donate and not be afraid. It covered areas of how anyone regardless of race could donate. Of course Archie was still concerned his "he-moglobins" would get mixed up with her "she-moglobins."
Blood centers started paying donors cash, thus encouraging IV drug users and others desperate for money. This blood was shipped worldwide.
It was finally figured out how to separate clotting factors for hemophiliacs. Thus one pint of HIV positive blood could easily be spread among a dozen people.
The Vietnam War also exposed America to heroin big time. Although heroine always was problematic, it became a real issue in the 1970s.
So what is this "Superstrain" we keep hearing about?
As we have learned viruses can "share" genetic information with each other. When an HIV patient stops taking his meds he gives the HIV virus a chance to regroup. This is why many drugs are often used to fight HIV. If one drug doesn't kill a type of HIV the other drug can do it. Using three or more drugs to fight HIV it is hard for the virus to mutate into something that will resist all the drugs
Eventually what will happen is we will get types of HIV that will not respond to current viral medicines. This will be a superstrain. Kind of a combination of subtypes of HIV all sharing genetic information.
So it's possible to be infected by more than one type of HIV?
Definitely it is possible; many cases have been isolated where the patient was subject to distinct subtypes of HIV-1. It is now known that the second type of infection often comes much later sometimes even years later, if the person continues to have unsafe sex.
So what does all this mean for a "cure."
What it means is that HIV is very complex and mutates a lot. This means any vaccine will not only have to effective against HIV-1 but all the subtypes of HIV-1. If a vaccine were developed it would probably be only effective against one type of HIV-1 group or subgroup.