Anthrax is a bacterial disease caused by Bacillus anthracis. It primarily affects herbivorous mammals, although other mammals and some birds have been known to contract it. Humans generally acquire the disease from infected animals or as a result of occupational exposure to contaminated animal products.
There are three types of anthrax in humans: cutaneous, gastrointestinal, and pulmonary. The vast majority of cases are cutaneous, caused by anthrax spores infecting a cut or abrasion. Anthrax is not transmitted from person to person, and can be treated with antibiotics.