Most seroepidemiologic studies of NoV have been based mainly on specific IgG antibodies, which are detected directly using NoV VLPs or P protein and always reflect cross-reactive antibodies left in the body from prior infection of a particular genotype, whose strong intragenomic cross-reactivity makes it impossible to distinguish between previous infections of different genotypes precisely (Parra and Green, 2014; Karangwa et al., 2017; Parra et al., 2017; Xie et al., 2020). This evidence concerns the gene OCA2 and infection.