1.Assessment of transmission capacity of influenza and effect evaluation of suspension measures in schools and nurseries
XU Yucheng, ZHANG Ruiyin, ZHOU Zhifeng, ZHONG Jianming, CHEN Haochuan, ZHAO Menglan, LI Xueyun
Chinese Journal of School Health 2021;42(2):273-276
Objective:
To estimate the transmission capacity of influenza clustering in schools and nurseries, and to evaluate the effect of suspension measures, providing a basis for formulating disease management strategies and control measures.
Methods:
The SEIAR dynamics model was used to simulate the epidemic data, calculating the basic regeneration coefficient R 0 of the epidemic to evaluate the epidemic transmission capacity, and calculating the cumulative incidence rate of the epidemic to evaluate the prevention and control effect of the suspension measures.
Results:
The basic regeneration coefficient R 0 was 8.44(8.01,8.89) without intervention. There were statistically significant differences in R 0 of influenza epidemic among different types of school(F=9.52, P<0.01). The R 0 of influenza epidemic in primary and secondary schools were higher than that in nurseries(P<0.05). R 0 of influenza A was higher than that of influenza B(t=2.71, P<0.01). R 0 of influenza A(H3) was higher than of influenza B(Victoria)(P<0.05). The cumulative incidence of the outbreaks which were suspended for 4 days and 7 days was significantly lower than that in the non-suspensions(P<0.05). However, there was no significant difference in the cumulative incidence of the outbreaks between the 4-day suspension and the 7-day suspension(P>0.05).
Conclusion
Transmission capacity of school-based influenza epidemic is high, especially among primary and secondary schools. When the epidemic situation of infected class meets the suspension standard, it is recommended to suspend classes for 4 days.