Scientists are afraid that the permafrost on Earth leaves ancient viruses

As Earth promptly thaws, scientists are more and more concerned potential risks which it bears for our ecosystems and personal health. One of the most disturbing threats is revival of the ancient viruses remaining in permafrost tens of thousands of years. This phenomenon can be a sign of even more serious consequences. According to the specialist in infectious diseases Birgitta Evengord from Umeo's University Umeå, about these ancient viruses still a lot of things are not known. She warns that there is "a factor of X" which we have to understand better to protect itself...