Laboratory Results for Case Classification
Confirmation of Y. pestis at a Reference Laboratory level
can be accomplished by one of the following sets of procedures:
- Positive DFA or DNA detection and bacteriophage lysis of
a recovered isolate.
- Appropriate titer change in paired serum sample testing.
Without an isolated culture (or 4-fold increase in titer), confirmation
cannot be verified and can only be considered as presumptive.
- Biochemical tests and the Antimicrobial Susceptibility
Test (E test) are also used at CDC to characterize the bacterium,
but are not considered to be confirmatory.
- Bacteriophage lysis
- Serology assays