More than 400 years ago, two people living in modern day Chile died while infected with the smallpox virus. Viral DNA found in their mummified remains has now yielded genetic evidence of when the disease arrived in the Americas. The findings, published on 30 July in Science1, confirm that Orthopoxvirus variola ' the virus that causes smallpox ' arrived in the Americas from Europe. The study adds to a small but growing body of evidence that the smallpox virus lost genes as it adapted to human hosts, a mechanism that related viruses, such as the one that causes mpox, might also be using today. 'We don't know anything about the recent history of viruses,' says Terry Jones, a computational virologist at Charite ' University Medicine Berlin. Studies such as this provide a rare snapshot into a pathogen's past, he says. Smallpox was one of the deadliest diseases in the world. The virus killed an estimated 300 million people in the twentieth century alone. Historical records suggest that...
learn more
