As if viruses weren't scary enough, scientists have found a 30,000 year old virus lying dormant in a patch of permafrost in Siberia. It gets even worse because the virus just happens to be giant-sized as well.
While scientists have determined that the virus currently poses no threat to both humans and animals, they also found that the virus became infectious again once it thawed from the permafrost. This has caused a certain amount of concern regarding other ancient viruses becoming active again once their icy prisons thaw upon exposure to warmer temperatures.
The giant virus was found buried 100 feet under the frozen Siberian permafrost. It was found by a team of researchers from the National Center of Scientific Research (CNRS) in France and researchers have dubbed it as Pithovirus sibericum. The ancient virus belongs to a class of giant viruses that was discovered a mere decade ago. The scientists working on the study have published their findings in the Proceedings of the National Academy of Sciences (PNAS).
"It comes into the cell, multiplies and finally kills the cell. It is able to kill the amoeba - but it won't infect a human cell," said Chantal Abergel, scientist from the CNRS who co-authored the study. "We are addressing this issue by sequencing the DNA that is present in those layers."
Unlike normal viruses, these giants can be observed using normal microscopes and the Pithovirus sibericum is the largest that scientists have found measuring up to 1.5 micrometres in length. Luckily, this specific virus only affects amoeba and they are currently harmless to humans.
The region where the virus was found has a thick coating of permafrost. However, research has shown that the permafrost is currently receding due to the effects of global warming. Scientists are now concerned that as the permafrost melts, other ancient viral threats may emerge.
"It is a recipe for disaster. If you start having industrial explorations, people will start to move around the deep permafrost layers," said CNRS scientist Jean-Michel Claverie. "Through mining and drilling, those old layers will be penetrated and this is where the danger is coming from."
Epidemiologists are also growing concerned that viruses such as smallpox, which have virtually been eradicated three decades ago may resurface in a similar manner to the giant virus.
"If it is true that these viruses survive in the same way those amoeba viruses survive, then smallpox is not eradicated from the planet - only the surface," said Claverie. "By going deeper we may reactivate the possibility that smallpox could become again a disease of humans in modern times."