Coxiellosis is a zoonotic bacterial infection associated primarily with parturient ruminants, although domestic animals such as cats and a variety of wild animals have been identified as sources of human infection. The zoonotic infection in people associated with Coxiella burnetii is widely known as Q fever. Coxiella is considered a potential agent of bioterrorism because of its low infectious dose, stability in the environment, and capability for aerosol dispersion.