Thirteen viruses of up to 48,000 years were thawed in the permafrost (permanently frozen ground) of Siberia. Researchers at the Aix-Marseille University, in France, reported in a study that the purpose of the procedure is to find out how the melting ice in the region can influence the spread of new pathogens, which can potentially cause a new pandemic.
The team of scientists responsible for the study says that “due to climate warming, the irreversible thaw of permafrost is releasing frozen organic matter for up to a million years” and therefore, the objective of the study is to specifically verify the “viruses that have remained dormant since prehistoric times” due to the possibility of contagion remaining, even after being frozen for so long.
How the study of viruses frozen for nearly 50,000 years took place
Belonging to five different classes, the thirteen pathogens (viruses in this case) were extracted from 7 different permafrost regions in Siberia. Sample sites vary widely, ranging from frozen mammoth droppings to Siberian wolf stomachs.
To test the capacity for infection after thawing the paleoviruses (paleo = old), the researchers used amoebae of the species Acanthamoeba spp. That done, they waited to see if the microorganisms would replicate inside the cells. Note that the team of scientists amoebas in order to prevent a possible spread of viruses in case an accident occurs.
Due to the fact that amoebas have genetic material that is very different from that of humans and other mammals, the researchers chose to use Acanthamoeba spp in testing the potential of paleoviruses for infection. In the end, scientists came to the conclusion that viruses “remained infectious after more than 48,500 years spent in deep permafrost.”
With the result of the study, the researchers from the Aix-Marseille University said that it is possible to extrapolate the case studied and say that the exact same thing can happen “for many other DNA viruses capable of infecting humans or animals”. That is, “ancient permafrost (eventually much older than 50,000 years) is likely to release these unknown viruses after thawing. (…) The risk tends to increase in the context of global warming, when permafrost thaw will continue accelerating and more people will be populating the Arctic in the wake of industrial developments,” the scientists said.
The study can be read in full in the bioRxiv open pre-publication repository, aimed at research in biological sciences.