Norovirus is a major cause of acute gastroenteritis, with at least 49 different norovirus genotypes. GII.4 genotype is responsible for the majority of norovirus epidemic outbreaks. The genotypes associated with medically-attended sporadic acute gastroenteritis are less clear.
Zaid Haddadin, MD, Einas Batarseh, MD, and colleagues compared the clinical characteristics and distribution of norovirus genotypes in children who sought medical care for acute gastroenteritis in three clinical settings (outpatient, emergency department, inpatient) over three years.
In 2,885 children, norovirus was detected in 22% of stool samples. Nearly 90% of the norovirus-positive samples were GII-positive, and GII.4 viruses were detected in 51% of the genotyped GII-positive samples. Seasonal variations were noted among different genotypes, and children with GII.4 infections were younger and had more severe symptoms requiring more medical care compared to children with non-GII.4 infections.
The findings, reported in Clinical Infectious Diseases, highlight the importance of continuous norovirus surveillance and could guide strain selection for candidate norovirus vaccines.