Climate change might thaw permafrost and release extremely old, unknown viruses and bacteria, researchers warn.
Marseilles – The climate change is in full swing and experts fear that rising temperatures might also thaw permafrost soils. Large areas of the Earth’s northern hemisphere are covered by permanently frozen soil. Animal carcasses and plant remains have been trapped in the ice for many thousands of years, as well as the bacteria and viruses that they contained when they were frozen.
Experts fear that if the permafrost thaws, ancient and previously unknown bacteria and viruses might also thaw. A team led by French researchers Jean-Marie Alempic and Matthieu Legendre from Aix-Marseille University has now been able to detect 13 previously unknown virus types in permafrost samples. They also managed to reactivate them, as the research team writes in a study that published on the preprint server bioRxiv, but has not yet been checked by experts. The study mentions “zombie viruses”.
Research team reactivates “zombie viruses” from the permafrost
The researchers have set a new record with the newly discovered “Pandoravirus yedoma”: According to the team, the virus has survived in the ice for almost 50,000 years. In the laboratory, it then became virulent once more in cell cultures. The research team had previously reactivated a 30,000-year-old virus that also originated in the permafrost.
Pandoravirus yedoma is a giant virus that infects amoebas. It is so large that it can be detected with a normal light microscope, how spektrum.de reported. The virus originated from an ice sample taken from below an arctic lake. The viruses were isolated from, among other things, the wool of mammoths and the intestines of a wolf. In cell cultures, they also infected amoebas and became virulent once more.
Climate change might release unknown viruses from permafrost
“It is likely that old permafrost will release unknown viruses as it thaws,” the researchers write in their study. According to the team, however, it is not yet possible to estimate how long the viruses will remain infectious. Eventually, they are exposed to outdoor conditions—UV light, oxygen, and heat. It also depends on how likely it is “that they will meet a suitable host in the meantime and infect it,” it continues.
The permafrost regions of the world
Permafrost is found on Earth in the polar regions and most of the high mountains on Earth. Russia is 65 percent permafrost, Canada up to 50 percent, and China up to 20 percent, while Greenland is 99 percent permafrost and Alaska is 80 percent.
Research team: “Global warming increases the risk”
However, the conclusion of the research team should make you sit up and take notice: “The risk will increase in connection with global warming if the thawing of the permafrost accelerates further and more people will colonize the Arctic in the course of industrial ventures,” write the authors in the study .
Recently, Chinese researchers discovered 900 never-before-seen microbial species in ice samples from 21 glaciers in the Tibetan plateau. These too might be released when permafrost thaws – the Researchers warn of possible new pandemicsthat might arise in this way. However, climate change might also work in another way promote pandemics and zoonoses. (tab)
