A ‘Zombie virus’ that lay frozen in permafrost for 48,500 years has been revived by scientists.
The thawing of permafrost is due to the rise in temperature in the Arctic and is potentially releasing viruses that have been dormant for tens of thousands of years, posing a risk to human and animal health.
The permafrost, which covers a fifth of the Northern Hemisphere, has preserved not only ancient viruses but the remains of extinct animals.
The Arctic region is warming up to four times faster than the rest of the planet, which is thawing the top layer of permafrost in the region.
Emeritus professor of medicine and genomics at Aix-Marseille University School of Medicine, Jean-Michel Claverie, has been testing samples taken from Siberian permafrost to see whether any viral particles contained within them are still infectious.
He has discovered five new families of viruses, and the oldest was almost 48,500 years old. Claverie warns that his research should not be considered scientific curiosity but a serious public health threat.
Traces of viruses and bacteria that can infect humans have already been found preserved in permafrost. This includes the lung sample of a woman exhumed from permafrost in Alaska containing genomic material from the influenza strain responsible for the 1918 pandemic and the mummified remains of a woman buried in Siberia, whose genetic signatures contained the virus that causes smallpox.
A 2016 anthrax outbreak in Siberia was also linked to the deeper thawing of permafrost during exceptionally hot summers, allowing old spores of Bacillus anthracis to resurface.