This document discusses Bacillus anthracis, the bacterium that causes anthrax. It causes three main types of anthrax infections - cutaneous, gastrointestinal, and inhalational. B. anthracis produces spores that allow it to survive in the environment for long periods. The spores must be autoclaved to be destroyed. When people become infected, the bacterium produces several virulence factors that contribute to its pathogenicity, including lethal factor, edema factor, and protective antigen. Laboratory diagnosis involves examining samples from blood, CSF, or skin biopsies under microscopy and culturing the samples to identify the gram-positive, spore-forming B. anthracis bacteria.