Number of cases.
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A recent study has shown that 2′-fucosyllactose (2′FL), a sugar found in human milk, can reduce the replication of human norovirus (HuNoV) in lab-grown human intestinal cells, suggesting it could become a treatment for norovirus infections. The research, published in Journal of Virology, focused on the GII.4 Sydney [P16] strain of HuNoV, one of the most common and globally widespread strains.
Human norovirus is a major cause of gastroenteritis, or stomach inflammation, leading to vomiting and diarrhea. There are currently no specific antiviral drugs for HuNoV. The virus binds to cells in the gut using molecules called histo-blood group antigens (HBGAs), which act as receptors on the surface of cells. Since 2′FL has a structure similar to these HBGAs, it can block the virus from attaching to and entering the cells.
The study tested 2′FL on human intestinal enteroids (HIEs), which are 3D models of human intestines grown in the lab. These models were taken from both adult and pediatric donors to better understand how 2′FL works across different age groups. The results showed that 2′FL significantly reduced HuNoV replication in several types of HIEs: duodenal and jejunal (parts of the small intestine) enteroids from multiple adult donors, all segments of the small intestine from an adult organ donor, and duodenal enteroids from two pediatric donors.
Although, the treatment was less effective in infant-derived HIEs. The reason for this difference is that the infant HIEs had much lower levels of α1–2-fucosylated glycans, the specific sugar molecules that are needed for HuNoV to bind. This suggests that the success of 2′FL in inhibiting the virus may depend on the presence of these glycans, which are present in higher amounts in adult tissues.
2′FL is already known to be safe and well-tolerated in humans, and it can be produced at scale, making it a promising candidate for further development as an antiviral treatment for HuNoV. While the study found no effect in infant models, the results highlight the potential of 2′FL in adult populations and open the door for more research into its use for norovirus gastroenteritis.
This study is particularly relevant given the recent rise in norovirus cases across the US. In December 2024, more than 22% of norovirus tests returned positive, compared to 12% during the same week in December 2023.2 The NoroSTAT report for the 2024–2025 season also recorded 495 outbreaks, a notable increase from 363 in the previous year.3 These statistics underscore the growing burden of norovirus infections, making the development of antiviral treatments even more urgent.
What You Need To Know
2′FL, a sugar in human milk, was shown to reduce human norovirus replication in lab-grown human intestinal cells, suggesting its potential as an antiviral.
The treatment was more effective in adult-derived cells, with less impact on infant cells due to lower levels of necessary sugar molecules.
The study’s findings are timely, given the recent rise in norovirus cases and outbreaks, highlighting the need for effective antiviral solutions.
Additionally, on January 2, 2025, the FDA issued a safety alert advising consumers and food retailers in Washington and Oregon to avoid shellstock oysters harvested between December 2 and December 17, 2024, due to potential norovirus contamination.4 This outbreak is a reminder of how quickly norovirus can spread, particularly through contaminated food sources, and highlights the need for effective therapeutic solutions.
Given the seasonal peak in cases and outbreaks, this study’s findings on 2′FL showing its potential to inhibit HuNoV replication in human intestinal enteroids are timely. If further research confirms these results, 2′FL could become an important tool in reducing the severity and spread of norovirus, especially in high-risk populations like the elderly, children, and immunocompromised individuals.
Overall, this study is a significant step toward developing targeted antiviral therapies for HuNoV, a virus that causes widespread illness, especially in vulnerable populations such as the elderly and young children.
