Development of a reverse transcription recombinase polymerase amplification assay with lateral flow dipstick for rapid detection of classical swine fever virus

Background: Classical swine fever (CSF), caused by the infection of Classical swine fever virus (CSFV), is a highly contagious disease of pigs and has caused significant economic losses in the pig industry. The rapid and effective detection of CSFV would contribute to the eradication program against CSF. Thus, this study aimed to develop a rapid and simple method for CSFV detection. Results: Here, a new method based on reverse transcription recombinase polymerase amplification (RT-RPA) coupled with lateral flow dipstick (LFD) was established for detecting CSFV. The RPA assay could be completed within 20 min at 37 o C and the results of the RPA assay could be visualized by LFD assay with the naked-eye inspection. This RT-RPA-LFD assay could be used to detect CSFV specifically, with no cross-reaction with other pathogens. Its detection limit was 10 pg of CSFV cDNA. Importantly, the RT-RPA-LFD assay has a good performance on the CSFV detection for clinical samples. Conclusions: The established RT-RPA-LFD assay greatly reduced the need for professional staff and sophisticated instruments and made disease detection convenient and feasible. This method would be useful for the prevention and control of CSF, especially in resource-limited settings.