Applications of a duplex reverse transcription polymerase chain reaction and direct immunofluorescence assay in comparison with virus isolation for detection of influenza A and B.

A duplex reverse transcription polymerase chain reaction (RT-PCR) and direct immunofluorescence assays (DFAs) were evaluated for detection of influenza types A and B in comparison with virus isolation in Madin-Darbin canine kidney cells. Four hundred four nasal wash were collected from individuals presenting with acute respiratory symptoms during 2001 to 2003 influenza seasons. According to the reference method, 78 (19.