In a follow-up to the report on the anthrax outbreak in the western Siberia region of Yamal, Governor Dmitry Kobylkin, declared a state of emergency as the number of human and animal cases increase during a heatwave on the Russian tundra.

Bacillus anthracis bacteria Image/CDC
Bacillus anthracis bacteria

The number of nomads affected by the bacterial pathogen has risen to 13 and the toll on the reindeer population is reported at 1,500, according to a recent Siberian Times report.

This is the first anthrax outbreak in the region in 75 years.

The temperature rise in the region, which is reportedly 10 degrees F above normal, may be to blame for the anthrax outbreak according to NBC News:

The carcass of a reindeer thought to have died from anthrax decades ago thawed and released the bacteria, sending the disease rippling through a population of animals already weakened by unusually high temperatures, according to local officials.

According to the Merck Veterinary Manual, Anthrax is a zoonotic disease caused by the sporeforming bacterium Bacillus anthracis. Anthrax is most common in wild and domestic herbivores (eg, cattle, sheep, goats, camels, antelopes) but can also be seen in humans exposed to tissue from infected animals, contaminated animal products or directly to B anthracis spores under certain conditions.

Depending on the route of infection, host factors, and potentially strain-specific factors,anthrax can have several different clinical presentations. In herbivores, anthrax commonly presents as an acute septicemia with a high fatality rate, often accompanied by hemorrhagic lymphadenitis.

B. anthracis spores can remain infective in soil for many years. During this time, they are a potential source of infection for grazing livestock. Grazing animals may become infected when they ingest sufficient quantities of these spores from the soil.In addition to direct transmission, biting flies may mechanically transmit B. anthracis spores from one animal to another.

People can get anthrax by handling contaminated animal or animal products, consuming undercooked meat of infected animals and more recently, intentional release of spores.