Evaluating the performance of VP1 expressed in baculovirus and Escherichia coli expressed from Senecavirus A in pig using an ELISA.

Senecavirus A (SVA) causes porcine idiopathic vesicular disease (PIVD), leading to economic losses in swine production. Rapid antibody detection is essential for monitoring herd immunity and controlling outbreaks. This study developed indirect ELISAs using SVA VP1 protein expressed in baculovirus and Escherichia coli (E. coli) systems. The optimized ELISAs showed high sensitivity (baculovirus: 100 %, E. coli: 96.67 %) and specificity (both 96.67 %) with a cut-off of 0.40. Both correlated strongly with virus neutralization assays (VNA) and showed no cross-reactivity with other porcine pathogens. The agreement with VNA was strong (κ = 0.839) for the baculovirus-based ELISA and moderate (κ = 0.731) for the E. coli-based ELISA. These findings suggest that SVA VP1 protein from both expression systems can serve as an alternative for ELISA-based serological diagnosis of SVA, aiding in herd immunity assessment and disease control.