A newly discovered mummified Lithuanian child dated in the 17th century could change the origin of small pox, revealing that the disease -- which was believed to have started in the ancient times -- could, in fact, have modern origins.

The new study, published in the journal Current Biology, states that by extracting the DNA from the mummified child, who is believed to have died from small pox, researchers have discovered that small pox is a modern killer and could have been the first disease to be treated via vaccine.

Previously, scientists believe that small pox, a viral deadly human disease, originated from ancient Egypt, India and China. In fact, historical accounts suggested that the Egyptian pharaoh Ramses V died from it.

However, the recent study shows that variola, the virus that causes small pox, could have evolved in recent times. The researchers came up with this conclusion by capturing the small pox DNA from the mummified Lithuanian child, and then sequencing and reconstructing the genome. The child was believed to have died between 1643 and 1665 during the outbreaks of small pox all over Europe. The reconstructed strain showed no indication of a live small pox virus, which meant that the discovered mummy was not infectious.

The researchers then compared the reconstructed strain from the mummified child to chicken pox samples from 1940 to 1977. Results showed that the small pox virus' ancestor is no older than 1580, which is much later than what scientists have previously estimated.

“This study sets the clock of smallpox evolution to a much more recent time-scale. Although it is still unclear what animal is the true reservoir of smallpox virus and when the virus first jumped into humans," said Eddie Holmes from the University of Sydney, Australia.

Meanwhile, Margaret Humphreys, a historian of medicine at Duke University, said via Eurasia Review, "This work blurs the line between ancient diseases and emerging infections. Much of smallpox evolution apparently happened in historic time."