Rapid Detection Assay for Infectious Bronchitis Virus Using Real-Time Reverse Transcription Recombinase-Aided Amplification

The infectious bronchitis virus (IBV) causes a severe infectious disease in poultry, leading to significant financial losses. The prevention and treatment of this disease are extremely challenging due to the virus's rapid mutation. Therefore, quick diagnosis of IBV infections is crucial for controlling the disease. This study aimed to develop a real-time reverse transcription recombinase-aided amplification (RT-RAA) method for IBV. The most effective primer combination was selected for further validation. To determine the assay's analytical sensitivity, a serial dilution from 10⁵ to 10⁰ EID₅₀/mL was used, and the limit of detection was calculated. The assay could detect down to 10² EID₅₀/mL. The limit of detection (95% Confidence Interval) was 67 EID₅₀ per reaction. There was no cross-reaction with common poultry diseases. When analyzing 39 clinical samples, RT-RAA and RT-PCR showed 100% diagnostic sensitivity and specificity. In conclusion, the IBV RT-RAA detection method is rapid, sensitive, and specific. This approach can be used to improve IBV diagnosis at the point of need.