A scientist is warning people need to be wary of ancient "zombie viruses" which could reawaken as Arctic permafrost melts.
It comes as Jean-Michel Claverie, Emeritus professor of medicine and genomics at the Aix-Marseille University School of Medicine in Marseille, and his team managed to revive a virus that spent 48,500 years frozen in permafrost.
Research published by Claverie and his team in February show a number of ancient viruses from Siberian permafrost samples were collected which could infect cultured amoeba cells.
The oldest of the virus strains was almost 48,500 years old.
It was collected from an earth sample at the bottom of an underground lake. Samples taken from the stomach of woolly mammoth remains were much younger at 27,000 years old.
Claverie told CNN the public needs to be aware that ancient viruses coming back alive could pose serious risks to modern society.
"We view these amoeba-infecting viruses as surrogates for all other possible viruses that might be in the permafrost," Claverie said.
"We see the traces of many, many, many other viruses, so we know they are there. We don’t know for sure that they are still alive. But our reasoning is that if the amoeba viruses are still alive, there is no reason why the other viruses will not be still alive, and capable of infecting their own hosts."
Claverie warned climate change sees an elevated risk of zombie viruses causing an issue.
"The risk is bound to increase in the context of global warming, in which permafrost thawing will keep accelerating, and more people will populate the Arctic in the wake of industrial ventures."