A report from a team of international scientists has revealed that long-held beliefs regarding the origin of the tuberculosis virus are wrong.

The report says the common belief TB began 10,000 years ago and spread from animals to humans is incorrect. The team says they have been able to prove the disease began in humans at much as 70,000 years ago.

“We found that the most basal – the earliest – lineages of TB and humans originated in the same place, in Africa, 60,000 years earlier than what people previously thought,” Professor Sebastian Gagneux said. “What we have done is provide a strong hypothesis to reinforce the idea that TB originally started in humans, and migrated to animals during NDT (Neolithic Demographic Transition).”

The group is now working to determine how the virus survived with such small clusters of humans. One of the features of TB is that it can lay dormant within a victim until years after initial infection. The scientists think that might be the reason the virus survived when it had so few hosts.

Tuberculosis kills about 1.4 million people worldwide every year.