Epidemiological characteristics of four clustered fever epidemics caused by enterovirus in Haidian district of Beijing in 2017

Abstract

Objective To analyze the epidemiological characteristics of 4 clustered fever epidemics caused by enterovirus in Haidian district of Beijing in 2017. Methods Field epidemiological investigation data of 4 clustered fever epidemics caused by enterovirus (including the basic information of patients, courses of onset, hospital visits and contact histories, as well as the scenes of the outbreaks and cluster activities) as well as laboratory testing data (including results of enterovirus detection and genotyping). Chi-sequare test was used to compare the attack rates of the clustered fever epidemics. Results A total of 62 cases were reported accumulatively. The median age of cases (P25, P75) was 5 (5, 10) years old. All epidemics occurred in September. Each two events were reported in primary schools and in child-care institutions, respectively. The attack rates were 35.8% (29/81) and 44.7% (33/74), respectively. The attack rates of boys and girls were 52.2% (36/69) and 30.2% (26/86), respectively. The difference was statistically significant (x2=7.68, P=0.006). The main symptoms of the cases were fever (98.4%, 61/62) and pharyngias (51.6%, 32/62). A total of 33 throat swabs were collected and 21 nucleic acid positive specimens were found, with a positive rate of 63.6%. Of the positive samples, 19 (90.5%) were positive for coxsackievirus A6 and 2 (9.5%) were positive for enterovirus. Conclusion Enterovirus can cause acute respiratory tract infections. Clustered fever epidemic caused by enteroviruses should be highly concerned, and the prevention and control measures should be strictly implemented. Key words: Enterovirus; Fever; Epidemiology; Clustered