This week, Bloomberg explored the so-called “zombie viruses” — long-dormant microbes, which they describe as “another risk to public health brought by climate change,” as lands frozen for “thousands of years” have begun to thaw, particularly in the Arctic. They noted that the warming rate in the Arctic is “faster than anywhere else on Earth.”
With Earth’s temperature having risen 1.2 degrees Celsius since pre-industrial times, scientists predict that by the 2030s, the Arctic region may experience ice-free summers. There is concern that as the permafrost in the region melts, hotter climates will release greenhouse gases like methane into the atmosphere. Last year, a research report published by a team led by virologist Jean-Michel Claverie revealed that they extracted various ancient viruses from Siberian permafrost, all of which remain infectious.
The ways in which these viruses could pose a threat continue to emerge. During a heatwave in Siberia in the summer of 2016, anthrax spores were activated leading to dozens of infections, resulting in the death of a child and thousands of reindeer. In July of this year, another team of scientists published findings that even multicellular organisms can survive in a dormant metabolic state (known as cryptobiosis) in permafrost conditions. They successfully revived a 46,000-year-old nematode from Siberian permafrost simply by rehydrating it.
In 2014, Claverie first demonstrated that “live” viruses could be extracted and successfully revived from Siberian permafrost. For safety reasons, his research only focused on viruses capable of infecting amoebas, as amoebas are far removed from humans, minimizing any risk of accidental contamination. However, he believes that the scale of the public health threat indicated by these findings has not been fully acknowledged or is perceived as rare. Hence, in 2019, his team set out to isolate 13 new viruses from seven different Siberian permafrost samples, including one virus that was frozen at the bottom of a lake over 48,500 years ago — proving the ubiquity of these viruses. In a research report published in 2022, he emphasized that if humans, animals, or plants were to be infected by viruses from unknown ancient pathogens, the result could be “catastrophic.”
He stated: “50,000 years ago, Neanderthals disappeared from this area.” “If Neanderthals died from an unknown viral disease, and this virus re-emerges, it could pose a threat to us.”