北京市2017—2018流行季流感感染率和发病率研究

Estimated infection rates and incidence rates of seasonal influenza in Beijing during the 2017-2018 influenza season

目的估算北京市2017—2018流行季流感的感染率和发病率。方法以北京市流感样病例监测和流感病原学监测系统报告的流感样病例数和流感病毒核酸检测阳性率为基础,结合显性感染率、分年龄组就诊率等参数,运用乘法模型,分年龄组估算流感感染率和发病率。结果北京市2017—2018流行季流感感染率为10.46%(95%CI:7.93%~14.29%),发病率为6.92%(95%CI:5.53%~9.03%),其中0~4岁组和5~14岁组发病率最高,分别为32.98%(95%CI:26.36%~43.06%)和21.66%(95%CI:17.36%~28.37%)。结论北京市2017—2018流行季季节性流感造成了巨大的疾病负担,尤其在0~4岁和5~14岁的儿童中负担更重,因此扩大和提高这两个年龄组儿童流感疫苗的覆盖率十分必要。

Objective The aim of the study was to estimate the infection rates and the incidence rates of seasonal influenza in Beijing in 2017-2018 influenza season. Methods A multiplier model was used to estimate the infection rates and incidence rates of seasonal influenza, taking the number of influenza-like illness (ILI) cases and the positive rates of influenza virus nucleic acid from the reports of ILI surveillance system and pathogenic surveillance system of influenza as the basis, along with the proportions of symptomatic infection, consultation rates by age groups and other relevant parameters. Results The estimated infection rate of influenza in Beijing during 2017-2018 influenza season was 10.46%(95%CI: 7.93%-14.29%). The incidence rate of influenza was 6.92%(95%CI: 5.53%-9.03%) with high incidence rates of 32.98%(95%CI: 26.36%-43.06%) and 21.66%(95%CI: 17.36%-28.37%) observed in the 0-4 years old group and 5-14 years old group, respectively. Conclusions Seasonal influenza brought substantial burden on health service in Beijing during the 2017-2018 influenza season, especially among children aged 0-4 and 5-14 years old. It is necessary to optimize the influenza vaccine coverage for both groups of children.