Bacillus anthracis is a type of aerobic spore-forming bacteria that causes anthrax disease.

Livestock may become infected by eating or inhaling anthrax spores. Humans, especially farmers and individuals who work in slaughterhouses, may develop cutaneous anthrax through skin exposure to infected animals.

Humans can also get inhalational anthrax by breathing in material contaminated with the bacteria.

Anthrax infection is usually diagnosed by identifying the bacteria within skin blisters, blood, or other body fluids. The anthrax serology test can determine if a person has been previously exposed to Bacillus anthracis.

The anthrax bacterium is a potential biological weapon. In 2001, bioterrorist activities involving the U.S. Postal Service infected 22 people with anthrax; 7 survivors had confirmed cutaneous anthrax disease. However, most bio-terrorism experts have concluded that it is technologically difficult to use anthrax effectively as a weapon on a large scale.

Reissman DB, Whitney EA, Taylor TH Jr, et al. One-Year Health Assessment of Adult Survivors of Bacillus anthracis Infection.  JAMA. 2004;291:1994-1998.

Inglesby TV, O'Toole T, Henderson DA, et al. Anthrax as a Biological Weapon, 2002. JAMA. 2002;287:2236-2252.