HIV is transferred through unprotected sexual intercourse (semen, vaginal fluids, pre-ejaculate); drug use or transfusion contamination (blood); or from mother-to-child (blood, milk). HIV is NOT transferred through hugging or kissing, sharing a cup or sitting on a toilet seat. It is critical to understand legitimate risks of transmission and to reject non-legitimate suggestions.
From Wikipedia: Estimated per-act risk for acquisition of HIV by exposure route (***note that risk rates may change due to other factors such as commercial sex exposure, phase of HIV infection, presence or history of genital ulcers, and national income levels.)
Exposure Route Estimated infections per 10,000
exposures to an infected source
Blood transfusion 9,000
Child birth 2,500
Needle-sharing 67
injection drug use
Percutaneous needle 30
stick
Receptive anal 170 ("best guess")
intercourse (2010) 143 (no condom)
Insertive anal 62 (uncircumsized)
intercourse (2010) 11 (circumsized)
Low-income country 38 ("best guess")
female-to-male
Low-income country 30 ("best guess")
male-to-female
Receptive penile- 10
vaginal intercourse
Insertive penile- 5
vaginal intercourse
Receptive oral 1
intercourse
Insertive oral 0.5
intercourse
Where did HIV/AIDS originate?
Although some alternative theories exist, the most widely accepted view of the origin of HIV/AIDS is transfer from primates to humans in the late 19th/early 20th century in sub-Saharan central Africa. Please read the following article (bolding added by me) to understand this predominate view.
ARTICLE - HIV origin 'found in wild chimps' from the BBC - 25 May 2006
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.
This was useful because University of Alabama at Birmingham 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 were 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 if 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."
According to Merriam-Webster online, zoonosis is "a disease communicable from animals to humans under natural conditions" like HIV coming from mutated primate SIV. For this to occur, six conditions must be met (citation - Wikipedia):
1. a human population;
2. a nearby population of a host animal;
3. an infectious pathogen in the host animal that can spread from animal to human;
4. interaction between the species to transmit enough of the pathogen to humans to establish a human foothold, which could have taken millions of individual exposures;
5. ability of the pathogen to spread from human to human (perhaps acquired by mutation);
6. some method allowing the pathogen to disperse widely, preventing the infection from "burning out" by either killing off its human hosts or provoking immunity in a local population of humans.
These condition were met for the SIV jump to humans (HIV) and also explains new animal-to-human illness like H1N1 and avian flu.
Treatment for HIV/AIDS -
One of the world's preeminent hospitals, the Mayo Clinic in Rochester, Minnesota, U.S.A. provides information on diseases including HIV/AIDS. Regarding treatment of HIV/AIDS, their web sites says:
"According to current guidelines, treatment should focus on achieving the maximum suppression of symptoms for as long as possible. This aggressive approach is known as highly active anti-retroviral therapy (HAART). The aim of HAART is to reduce the amount of virus in [the] blood to very low or even nondetectable levels, although this doesn't mean the virus is gone. This is usually accomplished with a combination of three or more drugs."
HAART (video here) is a combination of antiretroviral drugs given at different levels and doses depending on the specific needs of the patient. Although some people in MEDCs have difficulty affording such treatment (i.e. health care debate in the U.S.), the vast majority of infected individuals in LEDCs do not have access to this truly beneficial treatment which has extended and improved the lives of many since the end of the 1990s. Getting drugs to those without access physically or financially is a significant goal/challenge of UNAIDS and the UN in general.Video - occupational PEP
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