Walsh & Hoyt: Bacillus

Organisms of the genus Bacillus are gram-positive, spore-forming aerobic and facultative anaerobic bacilli. The spores are not formed in living animals or in humans. They are liberated by autolysis of the vegetative cells after leaving the host in body discharges. They remain viable for many years in the soil and thus are a potential source of infection. Like the bacteria themselves, the spores formed by Bacillus species can germinate in bothaerobic and anaerobic environments. The best known Bacillus species is Bacillus anthracis, the cause of anthrax, but lesser known species of Bacillus are responsible for the majority of CNS infections.