Therefore, we conducted histopathological studies in NOD/ShiLtj, Nfκb1 genetically modified 129P2 (B6), and F15-NOD mice to investigate myocarditis development after inoculation with influenza vaccine (influenza HA vaccine “KMB”) or HBV vaccine (Bimmugen). Here, NFKB1 is linked to myocarditis.