Application of RT-nested-PCR for RNA detection of swine influenza virus in clinical samples.

摘要

Pigs serve as major reservoirs of H1N1 and H3N2 influenza viruses which are endemic in pig populations worldwide and are responsible for one of the most prevalent respiratory diseases in pigs. Therefore the early detection and identification of such events are paramount in monitoring the spread of influenza viruses. Transfer of influenza A viruses from animal hosts to man may lead to the emergence of new human pandemic strains. The aim of this study was to test the matrix gene useful for reverse transcription nested-PCR for sensitive and specific detection of swine influenza A viruses in clinical samples. 75 RNA virus-positive samples from 235 samples, including nasal swabs, lung tissues and whole blood samples, were detected by RT-n-PCR. Using conventional virology method, 33 SIV strains were isolated in embryonated chicken SPF eggs. The results of PCR were 100% in agreement with those of virus isolation. The limit of detection of SIV was 10-7 EID50/0.1 ml. These results demonstrate the usefulness of RT-n-PCR for the detection and identification of influenza A virus in clinical samples..