Visual detection of porcine epidemic diarrhea virus by recombinase polymerase amplification combined with lateral flow dipstrip.

BACKGROUND: Porcine epidemic diarrhea virus (PEDV) is one of the most important enteric viruses causing diarrhea in pigs. The establishment of a rapid detection method applicable in field conditions will be conducive to early detection of pathogen and implementation of relevant treatment. A novel nucleic acid amplification method, recombinase polymerase amplification (RPA), has been widely used for infectious disease diagnosis. RESULTS: In the present study, a reverse transcription (RT)-RPA assay combined with lateral flow dipstrip (LFD) was established for the visual detection of PEDV by targeting the N gene. The RT-RPA-LFD assay detected as low as 102 copies/µL of PEDV genomic RNA standard. Moreover, the novel RT-RPA-LFD assay did not show cross-reactivity with common swine pathogens, demonstrating high specificity. The performance of the assay for detection of clinical samples was also evaluated. A total number of 86 clinical samples were tested by RT-RPA-LFD and RT-PCR. The detection results of RT-RPA-LFD were compared with those of RT-PCR, with a coincidence rate of 96.5%. CONCLUSION: The newly established RT-RPA-LFD assay in our study had high sensitivity and specificity, with a potential to use in resource-limited areas and countries.