Few disease pandemics are associated with as much intrigue, drama and historical mystery as HIV has been. Perhaps due in part to its status as an STD, the HIV virus has transformed the global culture around sex, and the reason for its spread has had as many scapegoats as evidenced culprits.

The amount of misinformation about where the virus comes from, how it spreads, and by whom has occasionally buried the real scientific investigation into the pandemic's origins under a deluge of cultural baggage. But now a comprehensive genetic tree of this notorious virus is finally revealing the truth about where and when HIV got its start.

Scientists are now fairly confident that HIV got its first foothold as far back as 1920, in the bustling colonial hub of Kinshasa in the Democratic Republic of Congo, reports Futurism.

Back in 1920, there was not yet a Kinshasa. The settlement was then known as the Belgian colony of Leopoldville, the capital of Belgian Congo. It was a high-profile place for young adventurers and prospectors to congregate, as well as a transportation polestar that had all the comings and goings required for a burgeoning pandemic to take hold. Needless to say, an environment like the one found in Leopoldville would also have had a scandalous subculture of sex workers and brothels.

This was the place where HIV-1 group M, the type of HIV that is responsible for 90 percent of all infections worldwide, first spread. And ironically, if it wasn't for this place, HIV may never have become the global scourge that it is today. That's because other HIV types (such as HIV-1 group M, confined to West Africa), though just as contagious, have not spread by such epic proportions.

It would appear that the environment of Leopoldville — and not the function of the virus — is the real root cause of HIV spreading globally.

"Ecological rather than evolutionary factors drove its rapid spread," explained Nuno Faria at the University of Oxford in the United Kingdom, one of the researchers on the study.

Faria and his colleagues made their discovery by building a family tree of HIV, derived from a host of HIV genomes collected from about 800 infected people from central Africa. By comparing genome sequences and counting the differences in them, the team was able to figure out when and where a common ancestor emerged.

It's a reminder that for public health intervention programs to succeed at halting HIV's status as one of the most devastating global pandemics to ever take hold — and to prevent similar future outbreaks from lifting off — it will take more than just a biological solution. It will take cultural and social solutions, too.

Scientists have pinpointed the exact city and year that HIV first spread
HIV might never have become a global pandemic if it wasn't for the ecology of what is now known as Kinshasa, and what was then a 1920s colonial hub.