A disease characterized by fever and leukocytosis that presents
in one or more of the following principal clinical forms:
Regional lymphadenitis (bubonic plague)
Septicemia without an evident bubo (septicemic plague)
Plague pneumonia, resulting from hematogenous spread in
bubonic or septicemic cases (secondary plague pneumonia ) or inhalation of
infectious droplets (primary plague pneumonia)
Pharyngitis and cervical lymphadenitis resulting from exposure
to larger infectious droplets or ingestion of infected tissues (pharyngeal
plague)
Plague is transmitted to humans by fleas or by direct exposure
to infected tissues or respiratory droplets.
Laboratory criteria for diagnosis
Isolation of Yersinia pestis from a clinical specimen,
or
Fourfold or greater change in serum antibody to Y. pestis
Case classification
Probable: a clinically compatible
illness with supportive laboratory results (demonstration of a single serologic
test result suggestive of recent infection with no history of immunization,
or demonstration of a Fraction I antigen in blood, bubo aspirate, or tissue
by antigen detection -- enzyme-linked immunosorbent assay (ELISA) or fluorescent
assay (FA))