Plague

what are the 3 manifestations of plague?

bubonic, septicemic, pneumonic

bubonic and septicemic

• most common form

• causes swollen lymph nodes (buboes) upon flea bite

• septicemic: bacteria travel to the blood

pneumonic

• bacteria that cause the disease can travel via aerosois (inhalation)

• most severe form

• highest fatality rate if untreated

etiological agent

yersinia pestis

yersinia pestis

• gram-negative, non-motile

  • grows optimally at 26 and 37

plague is the disease of…

rodents; humans are ACCIDENTAL hosts

transmission cycle involves…

rodents and their flees

purpuric lesions

hemorrhagic changes in skin

disseminated intravascular coagulation

purple finger tips

diagnosis

• clinical symptoms

• person resides in or traveled to plague-endemic region

  • samples from affected tissues that show “safety pin appearance”

treatment

reduces fatality rate

yersinia pestis is a…

BSL3 pathogen (indigenous and exotic)

bioterror weapon

• easy to obtain and mass produce

• delivered in aerosol form

• 10-100 bacteria are enough to cause the plague