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Virologist Jean-Michel Claverie says there are viruses
in the permafrost that are more than 50,000 years old. He said these could be
to humans. Professor Claverie said "
viruses up to a million years old" would be the
terrifying because they are
and we have never encountered them
. He added that deadly bacterial diseases like
and anthrax could be released on a large
. Factor X could pose even bigger problems. However, many scientists agree that a bigger danger from melting permafrost is the
of methane. This is a greenhouse
that is 80 times more harmful than CO2.
