Under the deep layered Siberian permafrost, scientists discovered a prehistoric virus called Mollivirus sibericum, the fourth prehistoric virus found since 2013. And scientists are planning to reanimate the "giant" virus they discovered in the northeastern part of Russia, the same location they found the Pithovirus sibericum virus last year.

A virus must be longer than half a micron to be classified as a "giant." Mollivirus sibericum, which means soft virus from Siberia, is 0.6 micron in size. Its genetic structure is so complex that it carries 500 genes, a big number of times greater compared with influenza virus' eight genes.

This plan was announced Tuesday by a team from the French National Centre for Scientific Research in a study published by the Proceedings of the National Academy of Sciences (PNAS) journal.

The study primarily aims to study ancient dormant virus because of the fear that climate change and increasing industrial exploration in the Arctic and Subarctic region will eventually awaken other dangerous pathogens. "The fact that two different viruses retain their infectivity in prehistorical permafrost layers should be of concern in a context of global warming," an abstract from a PNAS journal study said.

"If we can revive viruses at those depths and of that age, the chance is that other viruses will also be able to survive," says Jean-Michel Claverie, director of the Structural and Genomic Information Lab at Aix-Marseille University and one of the study's lead author. He further cited the already-declared extinct smallpox as an example, which is deadly to humans.

"I'm not saying that deep layers of permafrost are going to thaw tomorrow... but if you start mining for something, you will excavate layers of frozen soil by millions of tons... If there is something nasty there, it will be released in the atmosphere and [affect] the people," he added.

According to the latter, a few viral particles that are still infectious may be enough, in the presence of a vulnerable host; to revive potentially pathogenic viruses.  And if people are not careful and industrialize these areas without putting safeguards in place, they will run the risk of one day waking up viruses such as smallpox that they thought were eradicated.