A rapid on-site diagnostic method for goose parvovirus disease based on recombinase polymerase amplification and CRISPR/AsCas12a.

Goose parvovirus (GPV) is a highly pathogenic and lethal virus responsible for Derzsy's disease in goslings and ducklings, significantly influencing the economic viability of waterfowl farming. This necessitates the development of rapid diagnostic techniques for effective disease management. In this study, an optimized clustered regularly interspaced short palindromic repeats (CRISPR)/Acidaminococcus sp. CRISPR associated nuclease 12a (AsCas12a) system was developed for the diagnosis of GPV. The study determined that the optimal conditions for the CRISPR/Cas12a-based fluorescence assay were 20 nM AsCas12a, 5 nM crRNA, and 5 nM single-stranded DNA (ssDNA), whereas the lateral flow assay (LFA) required 20 nM AsCas12a and 4 nM crRNA. Moreover, the fluorescence-based assay and LFA achieved minimum detection limits of 7.8 copies/μL and 78 copies/μL, respectively, representing 1000-fold and 100-fold improvements over conventional PCR methods. Both detection methods exhibited high specificity and demonstrated no cross-reactivity with other prevalent waterfowl pathogens, such as duck plague virus, duck hepatitis viruses, H5 avian influenza virus, waterfowl astrovirus, reovirus, Muscovy duck parvovirus, and novel GPV. The results of the LFA were in complete concordance with laboratory qPCR analyses, thereby affirming their reliability for clinical diagnostics. In conclusion, we have successfully developed a dual-readout GPV detection system utilizing CRISPR/Cas12a technology, which holds significant promise for the early surveillance and containment of GPV outbreaks.