ObjectiveTo analyze the varicella cases from the illness-induced absenteeism system and the National Notifiable Disease and Reporting System （NNDRS） in primary and secondary school students in Minhang District， determine the characteristics of varicella-induced absenteeism in schools， and provide scientific evidence for the prevention and control of varicella in schools. MethodsSurveillance data of varicella-induced absenteeism and varicella cases in the NNDRS in 2021 were collected. Characteristics of varicella-induced absenteeism and consistency of data between the illness-induced absenteeism system and the NNDRS were determined， using descriptive analysis and matching varicella cases in the two systems. ResultsThe incidence of varicella in Minhang District was 48.28/10⁵ in 2021. The overall rate of illness-induced absenteeism was 612.08/10⁵ in primary and secondary schools， and the rate of varicella-induced absenteeism was 6.03/10⁵. The distribution of varicella-induced absenteeism was consistent with the incidence of varicella cases. Furthermore， the rate of varicella-induced absenteeism was significantly higher in boys than in girls. The rate increased synchronously during the peak of varicella incidence. The rate differed significantly across the students in diverse schools （χ²=135.217，P<0.001）， which was the highest in middle school students. However， there was no significant difference in the number of absent days between peak incidence and non-peak incidence periods of varicella （t=0.173， P=0.863）. Moreover， actual matching proportion of varicella cases between illness-induced absenteeism system and the NNDRS was 88.90%. The varicella cases that had been notified and those had not been notified in the NNDRS did not differ significantly in the number of absent days （t=0.346， P=0.730）. ConclusionThe incidence of varicella and varicella-induced absenteeism in schools is relatively low in Minhang District. Data between the illness-induced absenteeism system and the NNDRS is consistent. Routine prevention and control of varicella in schools is maintained a good level throughout the year.

ObjectiveThis study aimed to understand the epidemiological characteristics of hand-foot-mouth disease （HFMD） in Minhang District， Shanghai from 2009 to 2020， and provide a scientific basis for the prevention and control of HFMD. MethodsThe case information of HFMD was collected from the National Notifiable Infectious Diseases Reporting System of Chinese Center for Disease Control and Prevention. We used descriptive epidemiological methods to analyze the population characteristics， temporal and spatial distribution of HFMD， the pathogen composition of the case and its changing trend. ResultsFrom 2009 to 2020， a total of 66，198 cases of HFMD were reported in Minhang District， Shanghai， including 377 severe cases （severe case rate 0.57%） and 3 deaths （severs case fatality rate 0.80%）. There were more cases of HFMD in boys than in girls （1.5∶1）. HFMD patients aged under 5 years predominated， accounting for 88.91% of all cases. Majority of the cases （91.42%） were in scattered children （55.80%） and children in kindergartens （35.62%）. The incidence showed a cyclical trend， with low incidence years and high incidence years appearing alternately. The peak period was from April to July， and sometimes there were small peaks during October to December. A total of 12 years time-space scanning analysis revealed 3 clusters. The cluster centers were located in Wujing Town， Huacao Town and Xinzhuang Town， respectively. The proportion of EV71 in common cases was generally decreasing， and reduced to zero in 2019. The proportion of CoxA6 had increased year by year， and reached 75.00% in 2020. CoxA6 became the dominant pathogen in recent years. The number of severe cases had decreased year by year since 2010， and the dominant pathogen was EV71 （90.03% on average） in severe cases. ConclusionThe incidence of HFMD in Minhang District of Shanghai has a downward trend from 2014. The dominant pathogen changes from EV71 to CoxA6， and the dominant pathogen in severe cases is EV71. The discovered temporal and spatial clustering pattern is helpful for in-depth understanding of the distribution and epidemic trend of HFMD in Minhang District， and provides a scientific basis for epidemic prevention and control.