VP2-targeted sandwich ELISA (sELISA) enables direct detection of Senecavirus A (SVA)

Senecavirus A (SVA) is an emerging swine virus that causes vesicular lesions clinically indistinguishable from other high-consequence transboundary viral vesicular diseases, creating significant diagnostic and economic challenges. Rapid and specific detection of SVA is, therefore, critical for supporting foreign animal disease (FAD) investigations. In this study, we generated and characterized monoclonal antibodies (MAbs) targeting the SVA VP2 capsid protein, and assessed their performance in multiple immunoassay formats. Two MAbs, 2D1 and 7B3, demonstrated strong and specific binding to both recombinant VP2 and native SVA. Using these antibodies, we developed a sandwich ELISA (sELISA) capable of direct viral detection with a sensitivity of 60 pg/mL. This assay detects contemporary SVA strains and provides a rapid, high-sensitivity platform suitable for differential disease diagnosis of idiopathic vesicular disease. These VP2-directed immunoassays offer valuable tools to enhance SVA surveillance and streamline FAD investigative workflows.IMPORTANCESenecavirus A (SVA) produces vesicular lesions that are clinically indistinguishable from foot-and-mouth disease and other high-consequence transboundary viruses, making rapid and accurate differentiation essential during foreign animal disease (FAD) investigations. These investigations impose substantial operational and economic burdens, including movement restrictions and diagnostic delays caused by the lack of rapid, field-deployable testing tools. Current surveillance relies heavily on laboratory-based molecular assays, underscoring the acute need for a rapid, pen-side method capable of direct SVA detection. The monoclonal antibodies developed in this study target conserved, surface-exposed VP2 on the SVA capsid, enabling the first sandwich ELISA capable of detecting native virus with high sensitivity across circulating strains. This diagnostic platform provides a fast, inexpensive tool with the potential to improve differential diagnosis, accelerate FAD investigations, and reduce the operational disruptions associated with SVA-related outbreaks.