As warmer temperatures in the Arctic region continue to melt decades-old ice, a scientist in search of infectious particles in permafrost has found “zombie viruses.”
Jean-Michel Claverie, an Emeritus professor of medicine and genomics at the Aix-Marseille University School of Medicine in Marseille, France, found the particles in earth samples from Siberian permafrost, CNN reported on Wednesday.
As permafrost melts, dormant viruses in the frozen layer of soil beneath the ground could resurface and negatively affect animal and human health.
Permafrost covers a fifth of the Northern Hemisphere, the report said.
“The reason permafrost is a good storage medium isn’t just because it’s cold; it’s an oxygen-free environment that light doesn’t penetrate. But current day Arctic temperatures are warming up to four times faster than the rest of the planet, weakening the top layer of permafrost in the region,” the CNN report said.
Now, reportedly inspired by Russian scientists, in 2014, Claverie revived a virus from permafrost, making it infectious for the first time in 30,000 years by inserting it into cultured cells, according to the report.
“For safety, he’d chosen to study a virus that could only target single-celled amoebas, not animals or humans,” CNN added.
A similar experiment was repeated in 2015 where several strains of ancient virus samples taken from seven different places across Siberia showed they could be infectious, pointing at the larger issue of thawing permafrost.
“We view these amoeba-infecting viruses as surrogates for all other possible viruses that might be in the permafrost,” Claverie told CNN.
“We see the traces of many, many, many other viruses,” he added. “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.”
Trace amounts of viruses and bacteria that can infect humans have been found preserved in permafrost.
Citing examples, the CNN report said: “A lung sample from a woman’s body exhumed in 1997 from permafrost in a village on the Seward Peninsula of Alaska contained genomic material from the influenza strain responsible for the 1918 pandemic. In 2012, scientists confirmed the 300-year-old mummified remains of a woman buried in Siberia contained the genetic signatures of the virus that causes smallpox.”
Apart from deadly viruses, thawing of permafrost can also lead to unintended effects from buried waste from the mining of heavy metals and chemicals such as the pesticide DDT, banned in the 2000s.
Radioactive material dumped by Russia and the US can also have an effect.