An outbreak of anthrax has struck Siberia for the first time since 1941 -- and the thawing carcass of a victim of that last outbreak may be responsible.
The office of the governor of the Yamalo-Nenets Autonomous Region, in the western part of Siberia, confirmed on Thursday that the deaths of 1,500 reindeer over the past month were the result of the deadly disease, which is caused by the bacterium Bacillus anthracis. Thirteen hospitalized Yamal nomads, including four children, have not been confirmed to have the disease, but are being treated as if they do.
According to the Siberian Times, officials initially thought that the reindeer deaths and human illnesses were the result of a heat wave, after uncommonly high temperatures of up to 95 degrees F swept through the region. And, in a way, it seems they were: Officials with the Russian Ministry of Agriculture believe the cause of infection is the thawing of the frozen carcass of a reindeer that died 75 years ago. Reindeer, weakened by the heat, may have eaten the carcass, and then passed on the disease to the nomad herders.
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As Ben Guarino notes in the Washington Post, anthrax bacteria turn into spores in extreme cold, waiting in the soil for temperatures to rise. Some experts believe they may be able to survive in this form in permafrost for over a century; writing in 2011, Russian scientists warned that, "As a consequence of permafrost melting, the vectors of deadly infections of the 18th and 19th centuries may come back."
Gov. Dmitry Kobylkin has ordered that the most at-risk nomad herders in the area be evacuated and quarantined. Officials have been conducting a mass vaccination of surviving reindeer, and are also culling young animals that are unable to feed because their mothers have died. CNN reports that diesel fuel has been delivered to the region to burn the infected carcasses, but that officials have been hesitant to begin such burning because the extreme heat has left the area highly susceptible to wildfires.
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