[Analysis on influencing factors for acute gastroenteritis outbreaks caused by norovirus in Beijing, 2014-2018].

Objective

To analyze the influencing factors of acute gastroenteritis outbreaks caused by norovirus in Beijing from 2014 to 2018.

Methods

Data of acute gastroenteritis events caused by norovirus in Beijing from April 2014 to March 2018 were collected. Unconditional logistic regression model was conducted to identify the risk factors of the outbreaks.

Results

A total of 765 acute gastroenteritis epidemics caused by norovirus were reported in Beijing, in which 85.88% (657/765) were cluster events and 14.12% (108/765) were outbreaks. Among the outbreaks, 70.37% (76/108) were reported in 2017; 84.26% (91/108) were reported in winter and spring; 88.89% (96/108) were reported in kindergartens, primary or secondary schools; 81.48% (88/108) were through person-to-person transmission; 93.52% (101/108) were caused by norovirus GⅡ infection. The risk of outbreaks in suburban and out suburb area were 1.84 times (95%CI: 1.13-3.02) and 3.78 times (95%CI: 1.62-8.82) as high as that in urban area, respectively. The risks of outbreaks in primary, secondary schools and other institutions were 6.26 times (95%CI: 3.53-11.10), 14.98 times (95%CI: 6.23-36.01) and 8.71 times (95%CI: 3.07-24.71) as high as that in kindergartens, respectively. The risk of outbreak in which patients having lower hospital visiting rate than the median rate of all events was 2.29 times than that in the context of having higher hospital visiting rate (95%CI:1.42-3.68). The risk of foodborne outbreak was 14.55 times as high as that transmitted through person-to-person (95%CI: 3.15-67.07).

Conclusion

Measures such as strengthening the prevention and control of norovirus outbreaks in suburbs, primary schools, secondary schools and other institutions, promoting patients to visit the hospital actively, improving the management of foodborne events and kitchen workers should be taken to reduce the incidence of acute gastroenteritis outbreaks caused by norovirus.