Scientist revives a ‘zombie’ virus that spent more than 48 thousand years frozen

The virus was frozen in the permafrost of the Arctic.  The researcher fears that these beings still have conditions to be sources of infection.


Scientists have revived five families of viruses that were found frozen in the Arctic permafrost for 48,500 years.

These samples were taken from an underground lake 16 meters below the surface. The youngest date back 27,000 years and were found in the stomach of a woolly mammoth.

an environment of change

Permafrost covers a fifth of the northern hemisphere and has supported the arctic tundra and boreal forests of Alaska, Canada and Russia for millennia It serves as a kind of time capsule that preserves, in addition to ancient viruses , the mummified remains of various extinct animals that scientists have been able to unearth and study in recent years, including two cave lion cubs and a woolly rhino.

The reason permafrost is a good preservation medium is not just because of the cold; but it is also an oxygen-free environment in which light does not penetrate. But current Arctic temperatures are warming up to four times faster than the rest of the planet, weakening the top layer in the region.

Jean-Michel Claverie, emeritus professor of medicine and genomics at Aix-Marseille University, has analyzed soil samples from the Siberian permafrost to see if there are still viral particles that are still infectious: he has found them.

Through research published in the journal Viruses , Claverie and his team isolated several ancient virus strains from multiple samples. Of the five families, the oldest was 48,500 years old according to the soil radiocarbon record.

This family, despite their age, can still infect unicellular amoebas.


Curiously, although many articles try to point out that this type of activity does not cause problems for life, on this occasion the main researcher determines that he does worry that this discovery is perceived lightly.

He fears that people will view his research as a scientific curiosity and miss the possibility of ancient viruses coming back to life as a serious threat to public health.

“We see the traces of many, many, many other viruses ,” he added. “So we know they are there. We don’t know for sure if they are still alive. But our reasoning is that if the amoeba viruses are still alive, there is no reason why the other viruses are not still alive and capable of infecting their own hosts.”

Scientists don’t know how long these viruses could remain infectious once exposed to current conditions, or how likely the virus is to find a suitable host.