Implementation and Assessment of the Use of Real-Time PCR in Routine Diagnosis for Bordetella pertussis Detection in Brazil

Bordetella pertussis is the causative agent of pertussis. In Brazil, laboratory diagnosis of pertussis is based on the culture. In 2010, was standardized the Real-Time PCR TaqMan® in routine diagnosis. The aim of this study was to evaluate the impact achieved with the introduction of RT-PCR for the routine diagnosis of pertussis and to compare with the results obtained from culture. 4,697 samples of nasopharyngeal secretions collected from suspected pertussis cases and/or contacts were analyzed for RT-PCR and culture, from January 2008 until the end of December 2011. According to the results obtained from the samples 6.9% were culture/RT-PCR positive, 14.8% were positive only for RT-PCR and 0.2% only for culture. Negative samples for both techniques was 3,622 (77.1%) and 1.0% were inconclusive for RT-PCR. The implementation of RT-PCR in routine diagnosis resulted in an increase in laboratory confirmation by almost three times. The RT-PCR assay does not intend to replace the culture technique, but to promote an improvement in the diagnosis of pertussis.