Recently, a 30-thousand-year-old giant virus has been discovered and revived from the Siberian permafrost. This discovery was made by a group of scientists in France, who thawed the virus and discovered the virus that it had once existed during the time of Neanderthals. This virus is called a Pithovirus sibericum and while not dangerous to humans, it is able to infect tiny amoebas now that it is revived.
This discovery is intriguing for a couple reasons. First, it is a giant virus, and viruses traditionally are very small, usually measuring only 5-300 nanometers (nm). These viruses tend to be very simple viruses, with little genetic material. Giant viruses, however, such as the one recently discovered, possess much more genetic material. These giant viruses challenge many previous assumptions on the characteristics of viruses in general, potentially changing the way viruses are perceived. Other known families of large viruses—the Pandoravirus and Megaviridae virus—measure 1 micron (µm) and 1.25 µm respectively.
The newly discovered Pithovirus sibericum, however, is an even larger one at 1.5 µm. This means that a new family of giant viruses has been discovered.
Second, viruses are completely dependent on a host cell for survival. This means that without a host to live off of and feed on, the virus will quickly die. However, the fact that this virus has been able to be revived after 30,000 years means that this strain may be more resilient than once thought.
If this is found to be true, viruses, along with bacteria, have the potential to be released into the environment simply through the melting of the Arctic or through mining. With global warming increasing temperatures and with the arctic melting at increasing rates, the potential for a virus or pathogen to be released is particularly terrifying, especially if a correct host is present at the time. Deadly viruses once believed eradicated, such as smallpox, could therefore reemerge unexpectedly.
Currently, more research is being done on ancient layers of permafrost to investigate the survivability of viruses and bacteria, along with the ability to revive the viruses as well. Only time will tell whether or not more of such viruses will reemerge and possibly begin infecting humans.