Septicemic plague

Septicemic plague is one of three types of plague caused by Yersinia pestis, a gram-negative species of bacterium. Septicemic plague is a systemic disease in which Y. pestis rapidly infects the bloodstream, initially causing nonspecific symptoms including fever, chills, malaise, abdominal pain, diarrhea, and vomiting. As the disease progresses, disseminated intravascular coagulation causes internal and external bleeding, gangrene, and shock. Left untreated, septicemic plague is almost always fatal, sometimes within hours of initial symptoms. It is one of three forms of plague, along with bubonic (affecting the lymph nodes) and pneumonic (affecting the lungs) plagues. Septicemic plague is mainly spread by infected fleas that live on small mammals, but can also result from handling infected mammals. It can develop either directly from exposure to Y. pestis or as a complication of untreated bubonic plague. In the case of primary infection, Y. pestis bacteria enter the skin after a flea bite and travel throughout the bloodstream, showing no localizing signs of infection. This makes diagnosis difficult, as plague is generally rare and initial symptoms resemble several other, more common bloodstream infections. Diagnosis is made by finding bacteria in the bloodstream.