This image depicts the colonial morphology exhibited by colonies of Brucella abortus bacterial, which had been cultivated on chocolate agar, for a period of 48 hours.
Brucella species are facultative, intracellular, gram-negative coccobacilli. Nine species of Brucella are currently defined by phenotypic and antigenic differences, in addition to differential host specificity.
- Known human pathogens: B. abortus, B. melitensis, B. suis, and B. canis.
- Pathogenicity to humans of these species is not well known: B. ovis, B. neotomae, B. ceti, B. pinnipedialis, and B. microti.
Mode of Transmission