The origins of humans have been traced to Africa. And now, so have the origins of tuberculosis.New research shows the evolutionary trees of both humans and TB have grown side-by-side.TB bacteria originated in Africa at least 70,000 years ago.That’s the finding of a team of researchers led by Professor Sebastien Gagneaux of the Swiss Tropical and Public Health Institute. But why study the history of TB?Gagneaux said, “At the end of the day, it’s a certain kind of historic question and there have been long discussions about where TB came from originally.That’s on the one hand. On the other hand, the idea is that by learning from the past and how infectious disease evolves over time,this potentially could give us some clue about the future of the TB epidemic.”To trace the origins of TB researchers relied on genetic material, which is relatively easy to come by.“The trick is to use the genomic information that we can get from bacteria living today.That’s an approach which has been used for all kinds of other organisms, including humans, themselves.So we actually are learning a lot from what people are doing with human genetics,” he said.Gagneaux said that the evolutionary trees of humans and TB probably did more than just grow side by side.“I think that’s a nice way to put it. Maybe you can even say one inside the other. Imagine where the TB bacteria live, which is actually inside of human bodies. Yes, side by side, or one inside the other.”
