French scientists have ignited fears of an outbreak after reviving a "zombie virus" that had been trapped in a frozen lake for 50,000 years. Global warming has irreversibly begun to thaw vast areas of permafrost, "releasing organic matter frozen for up to a million years," according to the scientists. The oldest revived "zombie virus" has been named Pandoravirus yedoma, and was found in soil that was dated to be 48,500 years old.