Epidemiological and molecular investigation of a norovirus GII.17 outbreak in a kindergarten in Shanghai, China.

INTRODUCTION

Norovirus (NoV) is among the most prevalent pathogens responsible for non-bacterial acute gastroenteritis (AGE) in humans on a global scale.

METHODOLOGY

In September 2024, an epidemiological investigation and etiological analysis of a norovirus outbreak at a kindergarten in Shanghai Municipality of China was conducted to provide insights for preventing and controlling similar incidents in the future.

RESULTS

A total of nine cases of vomiting and diarrhea were reported in the outbreak, involving eight students and one teacher in the same class. The onset of symptoms was concentrated from 26 to 28 September. Nucleic acid tests detected the presence of the norovirus GⅡ positive in the anal swab samples of three cases, and Genotyping confirmed the presence of the GII.17 norovirus. Furthermore, the virus strains were found to be highly homologous in the RdRp region and VP1 region of the gene. Evolutionary analysis showed that the isolates from this outbreak had high homology with the strains circulating in Europe and the United States in 2022-2024.

CONCLUSIONS

It is necessary to strengthen the research on the molecular evolution of VP1 region of norovirus GII.17 genotype to prevent the emergence of new variants that could cause serious damage.