TULARAEMIAS CAUSED BY the intracellular pathogen Francisella tularensis, a small, pleomorphic, aerobic, Gram-negative coccobacillus which requires a complex cysteine-containing growth medium for laboratory cultures. Capsules may form in tissues. The…
AETIOLOGY ROCKY MOUNTAIN SPOTTED FEVER (RMSF) is caused by the rickettsial pathogen Rickettsia rickettsii, an obligate, intracellular parasite. These microorganisms are very small (0.3m-0.5m). Extracellular R. rickettsii ceases metabolic activity…
AETIOLOGY PLAGUE IS CAUSED BY the bacterium Yersinia pestis, a small Gram-negative, non-motile coccobacillus, which has a characteristics bipolar “safety-pin” appearance when stained. Although this organism is non-sporing, it may…
AETIOLOGY BRU CELLOSIS IS CAUSED BY organisms of the genus Brucella; particularly B. melitensis, B. suis and B. abortus. These organisms are small Gram-negative, aerobic, coccobacilli and are facultative intracellular…
AETIOLOGY ANTHRAX IS CAUSED BY the microorganism Bacillus anthracis, a large Gram-positive rod-shaped bacterium which is commonly found singly or in pairs. The organism is capsulated in clinical specimens, but…
