Scientists revive a 48,500-year-old virus and set a world record | smart news

Over the past 43 years, the Arctic has warmed almost four times faster than the rest of the world.
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As climate change accelerates the melting of ice in the Arctic, carbon dioxide emissions, habitat loss and sea level rise are not the only threats facing humans. Scientists have shown that ancient “zombie viruses” frozen for thousands of years can reawaken with rising temperatures.

In a paper posted on the bioRxiv preprint server in November, the scientists detail how several of these viruses revived from the Siberian permafrost. The oldest is a 48,500-year-old pandoravirus, which set a world record for the age of a restored virus, co-author Jean-Michel Claverie, a genomicist at Aix-Marseille University in France, tells New Scientist’s Michael Le Page.

All of the viruses the team discovered infect only amoebas and are therefore not direct threats to public health. But they were still alive and able to replicate, an indication that dormant viruses dangerous to humans could also revive by lurking in the ice.

“If the authors really are isolating live viruses from ancient permafrost, it’s likely that even smaller and simpler mammalian viruses would also survive frozen for eons,” Eric Delwart, a molecular virologist at the University of California, San Francisco, who was not involved. in research, he tells New Scientist.

In fact, one deadly outbreak attributed to melting permafrost has already occurred. In 2016, a heat wave in Russia thawed a 75-year-old frozen reindeer carcass infected with anthrax. As the disease spread, dozens of people were hospitalized, a child died and thousands of reindeer fell ill. The researchers warn that this may become more common.

“The public health risk comes from the accelerated release of previously frozen viruses combined with increased human exposure, as global warming is also making arctic areas much more accessible for industrial development,” Claverie tells Pandora Dewan. from Newsweek. However, Delwart tells New Scientist that a zombie virus is more likely to circulate in wild or domestic animal populations than it is to create a pandemic-scale outbreak in humans.

Claverie and his colleagues have previously discovered zombie viruses. In 2014, they revived a 30,000-year-old Pandoravirus. In their new paper, they describe 13 new viruses isolated from nine samples, including seven permafrost samples.

Permafrost covers about 24 percent of land surfaces in the Northern Hemisphere and makes up almost half of the organic carbon stored in Earth’s soil, according to the Arctic Institute. Just 3 degrees Celsius of warming could melt 30 to 85 percent of the top layers of permafrost in the Arctic. Exactly which microbes could resurface with this merger is unknown. A single gram of Arctic permafrost can contain hundreds or thousands of groups of microbes.

“We really don’t know what’s buried there,” Birgitta Evengård, a microbiologist at Umeå University in Sweden, told NPR’s Michaeleen Doucleff after the 2016 anthrax outbreak. “This is Pandora’s box.”

Rebecca Katz, a global health expert at Georgetown University who was not involved in the research, tells New Scientist that the dangers must be taken seriously.

“It makes sense to understand all the potential emergency pathways so we can be as prepared as possible,” he tells the publication. “Ancient viruses released by thawing permafrost are a very real threat.”

Arctic Climate Change Disease Microbes, Bacteria, Viruses New Research

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