BSCI 424 — PATHOGENIC MICROBIOLOGY —

Yersinia Summary

Yersinia pestis

Two epidemiological cycles of plague:

Sylvatic cycle with wild rodent reservoirs (e.g., prairie dogs, rock squirrels) and wild rodent flea vectors

Urban or domestic cycle with domestic rat reservoir and Oriental rat flea vector

Two clinical forms of epidemic plague:

Bubonic plague with characteristic lymph node (buboes) swelling which may progress to secondary pneumonic plague

Primary pneumonic plague is spread by infectious respiratory aerosols and is highly contagious

Yersinia enterocolitica

Common cause of enterocolitis in Scandinavian and colder areas of North America

Some studies show increased incidence during colder months which leads to the speculation that this organism may be more clinically active in cold climates, a hypothesis that parallels the observed increased metabolic activity at 22^oC to 25^oC

Epidemic outbreaks have been associated with contaminated meat or milk

In 1987, blood-transfusion related bacteremia and endotoxic shock was reported with organisms apparently able to survive and grow in nutritionally rich blood products that are stored by prolonged refrigeration

See CDC Plague HomePage

See CDC Emergency Preparedness & Response Plague Information

See Virtual Museum of Bacteria Related WebSite

See Family Practice Notebook Related WebSite

See RKM Yersinia pestis Image

See ASM Yersinia pestis Journal Review

Genus Yersinia has 11 species; 3 species are important human pathogens