The discovery and "revival" of a contagious giant virus, which had been buried in the frozen subsoil of Siberia for 30 thousand years, prompts scientists to warn of the possible re-emergence of other viruses and microbes and the return of widespread diseases that threaten humanity, such as science fiction movie script.
Scientists from France and Russia have discovered the giant virus in a sample of frozen ground from an area on its northeastern edge. Laboratory experiments subsequently demonstrated that the virus was again capable of attacking amoebae-single-cell microorganisms - although it does not pose a threat to multicellular organisms or to humans.
Although this particular virus is harmless to humans and animals, its "resurrection" is a warning sign of potential dangers it could bring to the light the melting of ice in remote areas due to climate change, because ancient pathogenic viruses could become active again.
The unusual oval virus (1,5 micrometers long and 0,5 micrometers wide) is 30% larger than the largest virus known to date, as well as some bacteria, which makes it visible with an optical microscope, without the need for an electronic one, such as it happens with other viruses. It has special characteristics and only a third of its proteins resemble those of other known viruses, so the scientists named it "Pithovirus sibericum", creating a new group.
The fact that giant viruses usually affect single-celled organisms (although exceptions have been identified) can not be a cause for complacency, as the prospect - whether due to global warming or mining activities in the Arctic for oil, and to "defrost" other ancient viruses could really bring out or restore old threats.
"The resurgence of viruses thought to have been eradicated, such as smallpox (whose propagation process is similar to that of pithovirus) should not be considered only theme science fiction," warns France's National Center for Scientific Research.
