A genus of parasitic bacteria, one of which causes the plague.
A genus of small rodlike Gram-negative bacteria that are parasites of animals and man. The species P. pestis causes plague in man, and P. tularensis causes tularemia.
A group of bacilli. They are essentially animal parasites that under certain conditions are transmitted to humans, and include the micro-organism responsible for plague and tularaemia.
A genus of gram-negative coccobacilli that causes disease in animals and humans. Pathogens once classed in this genus include Yersinia pestis (the microbe that causes plague) and Francisella tularensis (tularemia).