A simple and efficient method for detecting avian influenza virus in water samples

Waterborne transmission plays an essential role in the transmission and spread of avian influenza viruses. The abundance of influenza viruses in environmental water is usually extremely low and viruses or viral genomes can hardly be detected by conventional reverse transcription (RT-) PCR without concentration. In the present study, an electropositive filter membrane was used to concentrate influenza viruses from water sample, in addition, a glass fiber filter has been used prior to positive charged membrane for the prefiltration. Unlike the traditional adsorption-elution method, Trizol-LS reagent was used to lyse the viruses attached directly to the electropositive filter membrane and the influenza virus genomic RNA was extracted, followed by RT-PCR analysis. The method established in this study could improve the efficiency of the conventional RT-PCR technique used to detect the M, NP, and HA genes of influenza virus in natural water samples. This method could also reduce the time taken for the traditional adsorption-elution concentration procedure.