Anthrax is a potentially fatal disease of cattle, horses, sheep, and goats in underdeveloped agricultural regions of South and Central America, southern and eastern Europe, Asia, Africa, the Middle East, and the Caribbean as well as in wild livestock in Canada and the United States. Anthrax is caused by the bacterium Bacillus anthracis, which produces spores that spread the infection.

Anthrax can occur in humans who have been exposed to infected animals or animal products or to anthrax spores. Anthrax is not a contagious disease and cannot be spread from person to person. Humans can become infected with anthrax in three ways:

• Through a break in the skin (cutaneous anthrax)
• By eating contaminated food (gastrointestinal anthrax and oropharyngeal [back of the throat] anthrax)
• By breathing the bacterial spores (inhalational anthrax)

In a terrorist attack, bacteria such as Bacillus anthracis could be released into the air or in water or food. Anyone who inhaled, drank, or ate the bacteria could be infected.

Anthrax from all three types of exposure can be treated with antibiotics such as ciprofloxacin, doxycycline, or penicillin. Prompt treatment may help reduce the potential severity of the infection. There is also a vaccine against anthrax. Currently, this vaccine is not recommended or available for the general public.