The Origin of the HIV virus

 

HIV is a lentivirus, a virus that commonly lives in many animals, but doesn't always cause disease. The African Green Monkey has been found to have a type of the HIV virus, that enabled it to acquire AIDS. This and many other studies have lead scientists to suspect that HIV hasn't been a human virus for very long. If it were a virus with a lot of history with humans, it is unlikely it would still be so pathogenic.

 

Scientists believe HIV came to affect humans from a particular kind of chimpanzee in Western Africa. Humans probably came in contact with HIV around the time chimpanzees became a hunted species, for what is called "bush meat", and tribal groups began to eat infected animals. Recent studies indicate that HIV may have jumped from monkeys to humans as far back as the late 1800s, at earliest in 1931.

 

The earliest confirmed case of AIDS in humans comes from Kinshasa, the capital of the Democratic Republic of the Congo, identified from a preserved tissue sample in 1959. It is believed that the earliest strands of HIV that infected humans were more mild and usually died before they could do any serious damage to the immune system. It is thought that after multiple mutations over many decades, HIV evolved to become the fatal virus that we know today.

 

By 1969, the disease had jumped the Atlantic Ocean. The first known American, a Missouri teenager named Robert Rayford, was diagnosed and had died from AIDS. It is believed as a consequence of World War II, AIDS spread across Europe. The first indication of this was a wave of children dying from PCP, a disease that only targets those with weakened immune system. It is thought that the disease spread through the reuse of needles, a relatively common practice of the time. Surprisingly, approximately only one-third of the infected children died, suggesting the virus they contracted had not yet evolved into the lethal version we recognise today.

 

By the 1980s, being diagnosed with HIV was as good as a death sentence. Still without a cure, the number of people living with HIV continues to climb each year around the globe. It's only now after 35 years of research we can finally start to say with some confidence, where HIV first came from.