General Information: Avirulent species. Francisella novicida is closely related to Francisella tularensis, the causative agent for tularemia but is nonvirulent. This organism, however may cause disease in immunocompromised individuals. They do however cause a disease in mice that is very similar to tularemia. This strain was isolated from water in Utah, USA in 1950. Francisella tularensis is a non-motile, aerobic, rod-shaped Gram-negative bacterium and is the causative agent of tularemia.