Improved quadruplex real-time PCR assay for the diagnosis of diphtheria.

Diphtheria is caused by toxigenic strains of , and . For diagnostic purposes, species identification and detection of toxigenic strains (diphtheria toxin ()positive strains) is typically performed using end-point PCR. A faster quadruplex real-time PCR (qPCR) was recently developed (De Zoysa .