Anthrax

The bacteria Bacillus anthracis causes anthrax. The bacteria is a small aerobic or facultatively-anaerobic, gram-positive or gram-variable, encapsulated, spore-forming rod. The organism produces toxins which are important for clinical virulence. It grows well on blood agar resulting in large, irregular-shaped colonies. The origin of the name comes from the Greek word "anthrakis," meaning black, in reference to the necrotic lesion seen in cutaneous anthrax.

Although B. anthracis is generally an environmentally-stable and ubiquitous organism in nature, it has also been recognized as a potential pathogen that could be used as a biologic weapon.

Anthrax can affect the skin or internal organs. When inhaled, anthrax is usually fatal. Symptoms usually appear several days after the infection and this makes it difficult to track the organism.