Investigation of an outbreak of norovirus GⅡ.4P16 infection

  Objective   To analyze the epidemiological characteristics of an outbreak of norovirus GⅡ.4P16 infection in Shandong province in 2021, and provide evidence for the effective prevention and control of the outbreak.

  Methods   A field epidemiologic surveys were carried out. Water, stool and vomitus samples from the infection cases and anal swabs from some of close contacts were collected for pathogen testing and genotyping.

  Results   From 4 to 16 march, a total of 69 infection cases were found in the community. The main clinical manifestations included vomiting (76.81%) and diarrhea (69.57%). The attack rate was highest in children aged 0–5 years (20%). Clinical samples from 17 cases and two close contacts were tested norovirus GⅡpositive. GⅡ.4 P16 was the only genotype.

  Conclusion   The outbreak was caused by norovirus GⅡ.4P16 due to environment contamination by the vomitus of sick children and close contacts by the residents. The outbreak was controlled by taking timely detection and appropriate response measures.