The influence of COVID-19 prevention and control measures on the epidemic of influenza in Huzhou / 预防医学

Objective@#To evaluate the impact of coronavirus disease 2019 ( COVID-19 ) prevention and control measures in Huzhou on influenza epidemic strength and characteristics in 2020, so as to provide reference for formulating influenza prevention measures. @*Methods@#Using the influenza surveillance data of the national influenza sentinel surveillance system from January 2015 to July 2020, the seasonal characteristics of influenza epidemic were analyzed, the proportion of influenza-like illness cases ( ILI% ) and the positive rate of influenza virus in January to July of 2020 were compared with those of the same period in 2015-2019, in order to evaluate the impact of COVID-19 prevention and control measures. @*Results @#The ILI% and the positive rate of influenza virus in Huzhou were 3.90% and 15.32% during 2015-2019, while were 4.41% and 12.63% from January to July of 2020. The trends of ILI% during 2015-2019 fluctuated similar, but continued to drop since January 2020. The positive rate of influenza virus peaked from December to March in 2015-2019, also peaked from December 2019 to January 2020, but decreased to 0 in March. ILI% was positively correlated with the positive rate of influenza virus ( r=0.682, P<0.05). The growth rates of ILI% from January to July 2020 were 4.75%, -11.27%, 0.68%, 19.84% and 0.92%, compared with the same period of 2015-2019, respectively. The growth rates of ILI% in January 2020 were much higher ( >57.00% ) and from April to July were much lower ( <-33.00% ) . The growth rates of influenza virus positive rate from January to July 2020 were -47.96%, -36.53%, -3.44%, -35.92% and -39.37%, compared to the same period of 2015-2019, respectively. The growth rates of influenza virus positive rate in January 2020 were much higher ( >11.00% ) and from February to March were much lower ( <-61.00% ). @*Conclusion@#Since COVID-19 prevention and control measures were implemented in January 2020 in Huzhou, the ILI% and the positive rate of influenza virus in sentinel hospitals decreased significantly.

[A norovirus-borne outbreak caused by contaminated bottled spring water in a school, Zhejiang province].

OBJECTIVE: To study a local hospital reported acute gastroenteritis in a boarding school on its source of infection, mode of transmission and risk factors of the infection. METHODS: A suspected case was defined as who had developed diarrhea (≥ 3 times/day) or vomiting among teachers or students of the school, during April 19 - 30, 2010. A confirmed case was from a probable case plus tested positive for norovirus in stool specimens by using RT-PCR. Stool specimens of cases and environmental specimens were collected for laboratory diagnosis. In a case-control study, we compared exposures to sources of bottled water, consumption of bottled water, and hygienic habits of 220 probable or confirmed cases from April 21 - 23 in the peak of the outbreak, together with another 220 controls, with frequency-matched by school grade. RESULTS: 20.3% of the 1536 students but none of the teachers developed the disease. 98.6% of the cases (n = 217) and 85.5% (n = 188) of the controls had drunk bottled water in the classroom (OR(M-H) = 12.3, 95%CI: 3.7 - 40.9). 47.9% (n = 104) of the cases and 41.5% (n = 78) of the controls had drunk unboiled bottled water in classroom (OR(M-H) = 3.8, 95%CI: 1.5 - 9.6). 47.9% (n = 104) of the cases and 48.4% (n = 91) of the controls had drunk bottled mixed water (boiled and unboiled) in the classroom (OR(M-H) = 2.8, 95%CI: 1.1 - 7.0). Stool specimens from 3 cases and one bottle of uncovered bottled water in classroom showed positive of having norovirus genotype II. Coliforms was cultured much higher rates than standard deviations in the bottled water. The factory making the bottled water was not licensed or having strict disinfection facilities. CONCLUSION: Bottled spring water contaminated by norovirus was responsible for this outbreak.