The thawing of the permafrost due to climate change may expose a vast store of ancient viruses, according to a team of European researchers, who say they have found 13 previously unknown pathogens that had been trapped in the previously frozen ground of Russia's vast Siberian region.
The scientists found one virus that they estimated had been stranded under a lake more than 48,500 years ago, they said, highlighting a potential new danger from a warming planet: what they called "zombie" viruses.