Recombinant Polymerase Amplification Coupled with CRISPR/Cas12a Detection System for Rapid Visual Detection of Porcine Circovirus 3.

The porcine circovirus type 3 (PCV3) infection is an emerging disease associated with clinical signs of porcine dermatitis and nephropathy syndrome (PDNS)-like clinical signs. Currently, there is a lack of effective vaccines and therapeutics against this disease. Therefore, rapid, effective, sensitive, and specific detection methods are crucial for the timely identification, prevention, and control of PCV3. In this study, we developed one- and two-pot visual detection methods for PCV3 using a clustered regularly interspaced short palindromic repeat (CRISPR)/Cas12a detection system combined with recombinase polymerase amplification (RPA). These two methods demonstrated no cross-reactivity with eight other swine viruses and exhibited minimum detection limits of five and two copies of viral DNA, respectively, revealing their high specificity and sensitivity. During a clinical sample detection within 30 min, the coincidence rates between the one- and two-pot detection methods and real-time quantitative polymerase chain reaction (qPCR) were 100%. In conclusion, both one- and two-pot RPA-CRISPR/Cas12a detection methods have significant potential for the rapid, sensitive, and specific visual detection of PCV3.