It has been known that global warming is melting Arctic permafrost, but scientists have another thing to be worried about. According to a team of experts, melting Arctic permafrost would revive potentially all sorts of bad and very strange things like giant viruses.

The discovery of these viruses has been done from a single sample of the Siberian permafrost. The first called Pithovirus sibericum was discovered last year whereas the recently discovered is the Mollivirus sibericum.

The team’s findings were published this week in the Proceedings of the National Academy of Sciences. According to study researchers both the viruses are examples of rare giant viruses, e.g. those easily visible using optical microscopes.

According to an AFP report, this vital work was done in a top secret CDC lab. As per the report, the microbiologists behind the discovery have said that before ‘waking’ the virus up they will need to verify that it is harmless to humans.

The team comprising of researchers from institutions in France and Russia said that further their study will be accompanied by using the virus to infect single-celled amoeba, which will serve as its host.

Study co-author Jean-Michel Claverie said in a statement that very few viral particles that are still infectious will be enough to revive potentially pathogenic viruses. “If we are not careful, and we industrialize these areas without putting safeguards in place, we run the risk of one day waking up viruses such as small pox that we thought were eradicated”, he said.

All the viruses found as of now belong to pre-historic times. The first was discovered in 2003 with the identification of the Mimivirus family.