One of the most worldwide causer of severe gastroenteritis is Norovirus. This research will highlight the evaluating and relationship between Interleukin-12 (IL-12) and micronutrients (Vitamin A and Iron) levels in the serum of norovirus-infected patients compared with healthy controls. The total of samples is 103, the number of patients who are really infected by Norovirus was 62 whom aged 1–71 years while the total of healthy controls is 20; samples were collected during February 2026 in Tikrit hospitals. Results showed that IL-12 levels were significantly raised in patients, whereas Vitamin A and iron levels were significantly reduced (p ≤ 0.05) exception to this, two samples their Iron levels in serum somehow were elevated. The analysis program (One-way ANOVA) shown greatly significant differences between the two groups (p < 0.001). Effect size investigation had also presented large to very large effects (η² = 0.34–0.51). No correlations were saw between IL-12 and both Vitamin A or iron. These conclusions propose that activation of immune system for the duration of norovirus infection is powerfully associated with micronutrient exhaustion.