NFKB1 and viral infectious disease: However, on day 20 p.i., the levels of these cytokines were significantly higher in D2.129P2 (B6)-Nfκb1 homozygote mice than in D2.129P2 (B6)-Nfκb1 wild-type mice (p < 0.05), indicating a lack of clearance of viral infection, such as C. rodentium infection [13].