Table 5.

General Comments on Laboratory Diagnostics of Pertussis

• PCR and culture are most useful in the first 3 weeks after illness onset

• Serology should not be used to diagnose pertussis in patients <1 year after inoculation with an acellular or whole-cell vaccine formulation

• IgG anti-PT ELISA is preferred to IgA anti-PT testing because the IgA response following infection is less common, and thus a negative IgA anti-PT test should not be relied upon as diagnostic evidence of a pertussis infection

• The attendees strongly discouraged the use of DFA to detect B. pertussis. They also strongly discouraged the use of ELISA tests that employed whole B. pertussis as the antigen

Abbreviations: DFA, direct fluorescent antibody; ELISA, enzyme-linked immunosorbent assay; Ig, immunoglobin; PCR, polymerase chain reaction; PT, pertussis toxin.