Plague Home > Yersinia Pestis

Yersinia pestis bacteria -- the organism responsible for plague -- can grow with or without oxygen. Animals that are known to carry the bacteria include rats, prairie dogs, and fleas. During an outbreak, the bacteria can survive for months in cool, moist conditions, such as a rodent hole. Approximately 10 to 20 people in the United States develop an infection each year from flea or rodent bites.

What Is Yersinia Pestis?

Yersinia pestis are the bacteria that cause plague. This is a Gram-negative bacteria that can grow with or without oxygen (a quality called facultative anaerobic).
 

The Family of Yersinia Pestis

Yersinia pestis was formerly classified in the Pasteurellaceae family, but based on its similarities to Escherichia coli (E. coli), the Yersinia group has been reclassified as members of the Enterobacteriaceae family.
 
Although there are 11 named species in the genus Yersinia, only three are considered important human pathogens:
 
 
Yersinia pseudotuberculosis is the closest genetic relative to Yersinia pestis, but it can be distinguished from Yersinia pestis by the symptoms it causes and by laboratory test results. Neither of these bacteria frequently infect humans, in contrast to Yersinia enterocolitica, which accounts for 1 to 3 percent of diarrhea cases caused by bacteria.
 

Yersinia Pestis in Animals

Yersinia pestis is found most commonly in rats, but occasionally in other animals, such as:
 
  • Mice
  • Squirrels
  • Fleas
  • Cats
  • Dogs
  • Lice
  • Prairie dogs
  • Wood rats
  • Chipmunks.
     
Other, less frequent sources include wild rabbits and wild carnivores that pick up their infections from wild rodent outbreaks.
 
Deer mice and voles (field mice) are thought to maintain Yersinia pestis in animal populations, but are less important as sources of human infection.
 
Written by/reviewed by:
Last reviewed by: Arthur Schoenstadt, MD
Last updated/reviewed:
List of references (click here):
Other Articles in This eMedTV Presentation
Advertisement


Topics

Quicklinks

Related Channels

eMedTV Links
Copyright © 2006-2017 Clinaero, Inc.

eMedTV serves only as an informational resource. This site does not dispense medical advice or advice of any kind. Site users seeking medical advice about their specific situation should consult with their own physician. Click Terms of Use for more information.

This site complies with the HONcode standard for trustworthy health information:
verify here.