Warda E Rusdi^{1, 2}, Soetjipto Soetjipto³ , Maria I Lusida^{4, 5}, Irmawan Farindra⁶, Muhammad S Rusdi⁷, Mahdiyah Hasna⁸, Hidayat Hidayat⁸, Wilhemus DMR Benge⁹

Abstract

Purpose: To examine the potential of vitamin D supplementation in reducing norovirus replication and alleviating diarrhea severity in a murine model. Methods: This study involved three groups of mice (n = 7 mice/group): Group K (-), Group K (+) and Group P. Mice in the K (+) and P groups were intraperitoneally inoculated with 1 mL of Human Norovirus (HuNoV) suspension, containing approximately 10? genome copies per mL. Thereafter, mice in the treatment group received oral vitamin D3 once daily for five consecutive days, at a dose of 0.75 μg/kg body weight. Diarrhea severity was assessed daily starting from day 1 post-infection using the paper towel method by scoring fecal moisture and consistency. On day 8 post-infection, mice were sacrificed using an overdose of anaesthetic agents and colonic fecal samples were subsequently collected for RT-qPCR analysis to quantify the viral load. Results: Mice receiving vitamin D3 supplementation exhibited a significant reduction in viral load compared to the untreated group (p = 0.000). Additionally, treatment groups showed improved fecal consistency, indicating a protective effect on intestinal tissue. Conclusion: Vitamin D3 administration reduces norovirus viral load and mitigates diarrhea severity in BALB/c mice infected with HuNoV. Therefore, vitamin D3 could be used as an adjunctive therapy for viral gastroenteritis.