Anthrax is a life-threatening infectious disease caused by Bacillus anthracis that normally affects animals, especially ruminants (such as goats, cattle, sheep, and horses). Anthrax can be transmitted to humans by contact with infected animals or their products. In recent years, anthrax has received a great deal of attention as it has become clear that the infection can also be spread by a bioterrorist attack or by biological warfare. Anthrax does not spread from person to person and is not considered contagious.

    There have been a number of outbreaks over the years that are usually localized. Most recently in 2016, in Siberia, Russia, there was a major outbreak of anthrax that sickened at least 13 Siberian people and killed over 2,000 reindeer. Authorities believe that the melting permafrost unburied a reindeer that died of anthrax 75 years ago, causing the release of anthrax spores.