Vast stretches of permafrost are melting as the Earth’s polar regions warm, thawing ancient viruses and bacteria that had remained frozen for tens of thousands of years. Behind the lurid headlines about “zombie viruses,” there’s some fascinating science — and a warning.
Last month, scientists announced they’d taken a sample of tundra from Siberia, extracted a virus that had been frozen for 50,000 years, and showed it was still capable of infecting its normal host — amoebas. It was not only a virus new to scientists but also a member of an intriguing group of giant viruses. These are shaking up scientists’ understanding of how viruses evolved, representing a sort of missing link with other life forms.
So the size and the age of this virus are both scientifically noteworthy — and the fact that it can cause infections after being frozen since the stone age should be a little scary. That’s not because this specific virus will adapt itself to infect humans but because it means other viruses that might be more dangerous to us could also be lurking down there.
