By evaluating the association between NPC-enriched oral microbes and serum EBV-VCA IgA antibody levels, we found that moderate but significant association between the abundance of Streptococcus sanguinis ASV1b51 and serum EBV VCA-IgA antibody levels (Spearman correlation, R = 0.20, P = 0.001) (Fig. 2a). This evidence concerns the gene CD79A and nasopharyngeal carcinoma.