For the first time since 1941, anthrax has hit Western Siberia, with 1,500 reindeer dying and 13 Yamal nomads being hospitalized including 4 children.

This is because unusually high temperatures (it’s 10 degrees Fahrenheit higher than normal) have melted permafrost containing the corpse of a reindeer that died of the bacteria 75 years ago.

Anthrax goes dormant when frozen, turning into a spore that reanimates when the temperature rises. Scientists estimate it can survive in this state for a minimum of 100 years.

In Siberia, dozens of herders have been relocated, a quarantine is in place and a state of emergency has been declared by the mayor.

This renews concerns that ancient viruses and bacteria could once again pose a threat, as the earth warms.

In 2014 scientists discovered that a Siberian virus, pithovirus sibericum, which lay dormant in permafrost for 30,000 years, became infectious again once thawed.

Giant virus resurrected from 30,000-year-old ice (Nature News)

Scientists have revived a giant virus that was buried in Siberian ice for 30,000 years — and it is still infectious. Its targets are amoebae, but the researchers suggest that as Earth’s ice melts, this could trigger the return of other ancient viruses, with potential risks for human health.

The newly thawed virus is the biggest one ever found. At 1.5 micrometres long, it is comparable in size to a small bacterium. Evolutionary biologists Jean-Michel Claverie and Chantal Abergel, the husband-and-wife team at Aix-Marseille University in France who led the work, named it Pithovirus sibericum, inspired by the Greek word ‘pithos’ for the large container used by the ancient Greeks to store wine and food. “We’re French, so we had to put wine in the story,” says Claverie. The results are published in Proceedings of the National Academy of Sciences1

Larger than some bacteria, this virus — seen in a cross-section under a transmission electron microscope — was still able to infect amoebae despite having spent 30 millennia in a frozen state. Julia Bartoli & Chantal Abergel; Information Génomique et Structurale, CNRS-AMU