PEDV-challenged protection during the first infection was positively correlated with IgA and IgG antibodies in intestinal-associated lymphoid tissues and blood (de Arriba et al., 2002), indicating that VN antibody can be detected in piglets inoculated with PEDV JS-A, and the titer of VN antibody gradually increases and remains high at the end of the experiment (Chen et al., 2016). This evidence concerns the gene CD79A and infection.