Development and application of a CRISPR/Cas12a-based reverse transcription-recombinase polymerase amplification assay...

Getah virus (GETV), a mosquito-borne alphavirus classified as a zoonotic disease, primarily infects livestock, particularly pigs and horses. In recent years, it has re-emerged in multiple Asian countries, posing a potential threat to animal husbandry and public health. In this study, we developed a rapid and sensitive GETV detection method based on reverse transcription-recombinase polymerase amplification (RT-RPA) and the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system combined with a lateral flow dipstick (LFD) for visual readout. By leveraging sequence conservation in the GETV E2 envelope protein-coding regions, we engineered matched crRNA guides and amplification primers to develop a rapid CRISPR-Cas12a diagnostic workflow. The optimized platform combines RT-RPA (42 °C/20 min) with Cas12a's trans-nuclease activity, permitting multiplex detection via real-time fluorescence quantification or immunochromatographic strip visualization. Analytical evaluation demonstrated a detection capability of 10 copies/µL and exclusive specificity against four pathogen controls, including Japanese encephalitis virus and pseudorabies virus. Validation performed using simulated clinical samples revealed 100% concordance between the results of RT-RPA-CRISPR/Cas12a-LFD and quantitative polymerase chain reaction (PCR), while reducing the total detection time to 50 minutes. This approach eliminated the need for advanced instrumentation owing to its simplified operational design, enabling field-deployable rapid detection capabilities that establish essential technical infrastructure for initiating timely GETV containment measures. This approach has broad application potential in the fields of food safety, clinical diagnostics, and environmental science.