Since the 1980s there have been many theories offered as to the origins of AIDs from eating monkey brain to an inappropriate interspecies relationship. More recent evidence, using DNA analysis and viral forensics, has come up with what many scientists now believe to be the definitive answer to how AIDS started and how it spread around the world. In order to understand the spread of AIDS, we need to look at origin of its cause – human immunodeficiency virus (HIV).
There are actually two strains of HIV, HIV-1 (the most common) and HIV-2 (a rarer form, mostly relegated to parts of Western Africa). HIV is the human version of a particular strain of simian immunodeficiency virus (SIV) known as SIVcpz. SIVcpz formed in some chimpanzees who ate different types of smaller primate meat (red-capped mangabey and greater spot-nosed monkey), each of which had a different type of SIV that fused into SIVcpz. It was the SIVcpz strain that made the jump from chimpanzee to human.
The belief is that in 1908, in a small village located in southeastern Cameroon, a hunter was infected with the blood of a chimpanzee carrying SIVcpz. While the human body would normally fight off an SIV infection, this time it did not. From Cameroon, the virus slowly made its way to 1920s Kinshasa. At this time, Kinshasa (or Leopoldville as it was then called) was a booming town of Belgian Congo. Millions of people used the well-developed transportation system to travel in and out of the city. From around 1920 until the end of Belgian colonialism in 1960, the disease spread among the population. However, due to an already low life expectancy and the prevalence of several other diseases in the area, HIV/AIDS went unnoticed and undiagnosed.
During the time of Belgian colonialism, there were no Congolese doctors. The Belgian colonizers had discouraged education and instead brought in Haitian doctors. When the Haitians returned to their home, some of them brought a strain of the M subgroup of HIV-1 known as HIV-1 subtype B. In the early 1970s an American investor from Miami opened a blood plasma clinic, where people could get a liter of plasma for $3. Under the Duvaliers, Haiti did not do rigorous checks of their blood and plasma supply and soon the virus was infecting plasma sent to the United States.
The HIV-1 virus had already spread to the US by the 1970s, but it wasn’t until 1981 that people started to notice something different- labeling it a gay disease. In 1982, the term AIDS was first used to describe a set of conditions that included a type of cancer known as Kaposi’s sarcoma and pneumonia. In 1983, HIV was found to be the root cause of AIDS.Due to a global culture of travel, promiscuity, and drug abuse, HIV-1 subtype B has gone on to infect about 75 million people worldwide. From the quiet forests of Cameroon to the burgeoning railways of Leopoldville (Kinshasa) all the way to the bustling modern capital cities, AIDS has had an incredible journey that can only be seen as one of the most unfortunate stroke’s of luck the world has ever seen.