Smallpox found in Lithuanian mummy could rewrite virus' history

The mummy of a child discovered in a crypt beneath a Lithuanian church harbors the oldest sample found to date of the virus that causes smallpox, a new report said. But the researchers' analysis of the virus, called the variola virus, suggests that smallpox first appeared in humans much more recently than thought, the researchers said. Scientists had thought that smallpox was an ancient disease that plagued humanity for millennia. The researchers drew their conclusion by taking virus from the mummy of the child, who lived between 1643 and 1665, and comparing that strain against variola viruses that date to the mid-1900s. The differences, or mutations, that the researchers found suggest that the strains shared a common ancestor that first arose between 1588 and 1645, the researchers said. That time period was filled with human exploration, migration and colonization — activities that could have spread the virus worldwide, the researchers noted. More studies are needed to confirm that the smallpox virus indeed arose that recently, but if it did, this would cast doubt on the previously suggested idea that people in ancient Egypt had smallpox. Although 3,000- to 4,000-year-old Egyptian mummies have pockmark scarring, a symptom of smallpox, these scars could have also come from measles or chickenpox, said the study's first author, Ana Duggan, a postdoctoral fellow at the McMaster University Ancient DNA Centre in Canada.