Development of a real‐time recombinase polymerase amplification assay for rapid detection of Aeromonas hydrophila

Abstract Aeromonas hydrophila is ubiquitous in the aquaculture industry and a constant cause of severe disease and economic losses. The early diagnosis of these infections is crucial for disease surveillance and prevention. We developed a real‐time recombinase polymerase amplification (real‐time RPA) assay for detection of A. hydrophila using the haemolysin gene. The assay was performed at 37°C for 20 min and was highly specific with no cross‐reaction with other fish pathogens or with other Aeromonas species. The assay detection limit was 10 2 copies of the Aeromonas hydrophila per reaction. Compared with traditional culture‐based method or real‐time PCR, the diagnostic sensitivity and specificity of the real‐time RPA were 73.7 and 100%, as well as 64.7 and 93%. Our newly developed real‐time RPA was specific and sensitive and can be used in large‐scale and point‐of‐care field investigations of A. hydrophila infections to enable earlier diagnoses.