Annals of Disaster Medicine

ISSN:1684-193X

Abstract ---Plague is a zoonotic illness caused by the Gram-negative bacillus Yersinia pestis. Human are not necessary for persistence of the organism, and we acquire plague from animal fleas, contact with infected animals or rarely from other humans via aerosols or direct contact with infected secretions. To be able to differentiate endemic plague from plague used in biological warfare, medical officers must understand the typical way in which humans contract plague in nature: First, a die-off of animals in the mammalian reservoir that harbors bacteria-infected fleas will occur. Second, troops who have been in close to infected mammals will become infected. By contrast, plague will spread via aerosols in the most likely biological warfare. A rapid person to person spread of fulminant pneumonia would then occur. If an enemy force is to release fleas infected with Y pestis, then people would present with classic bubonic plague before a die-off in the local mammalian reservoirs occur. The three clinical forms of human plague are bubonic, septicemic and pneumonic. Bubonic plague, characterized by painful lymphadenopathy and severe constitutional symptoms of fever, chills and headache, is the most common form. Septicemic plague without localized lymphadenopathy occurs less commonly and is difficult to diagnose. Primary pneumonic plague is spread by airborne transmission and has the highest mortality. Diagnosis is established by identifying the organism from blood or other body fluids. Patients should be isolated initially and treated with antibiotics (streptomycin preferably) early. A killed, whole-cell vaccine is available to protect humans against bubonic plague, but not against for primary pneumonic plague.