RAPID DIAGNOSIS OF HUMAN PARAINFLUENZA VIRUS TYPE-1 INFECTION BY QUANTITATIVE REVERSE TRANSCRIPTION-PCR-ENZYME HYBRIDIZATION ASSAY

The detection and quantitation of human parainfluenza virus type 1 (HP IV-1) RNA in nasal wash specimens from 49 children with lower respirat ory infections were performed by a reverse transcription-PCR-enzyme hy bridization assay (RT-PCR-EHA), The HPIV-1 RT-PCR-ENA was then used to test 40 samples from asymptomatic children, Primers and probes were d esigned from regions within the HPIV-1 hemagglutinin-neuraminidase gen e which are highly conserved among all known genotypes. HPIV-1 was det ected in all nine children who were culture positive, Other common res piratory viruses (HPIV-2, -3, and -4, mumps virus, respiratory syncyti al virus, measles virus, and influenza virus) were not detected by the HPIV-1 assay, Forty symptomatic children were negative by culture, an d four of these were positive by RT-PCR-EHA. All of the samples from a symptomatic children were negative by culture and RT-PCR-EHA, RT-PCR-E HA was 100% sensitive (95% confidence interval, 0.66 to 1.00) and 95% specific (95% confidence interval, 0.88 to 0.99) compared with culture . The four false positive results (relative to the results of culture) were in children with lower respiratory infections compatible with HP IV-1 infection and suggest that RT-PCR-EHA may be more sensitive than culture, Our data indicate that HPIV-1 may be underdiagnosed by routin e culturing methods. RT-PCR-EHA has been demonstrated to be an easy, r apid, sensitive, and specific test for diagnosing HPIV-1 infection and provides a methodology for the rapid detection of closely related res piratory viruses.