Mortality burden from seasonal influenza in Chongqing, China, 2012-2018

Li Qi; Qin Li; Xian-Bin Ding; Yuan Gao; Hua Ling; Tian Liu; Yu Xiong; Kun Su; Wen-Ge Tang; Lu-Zhao Feng; Qi-Yong Liu

doi:10.1080/21645515.2019.1693721

Mortality burden from seasonal influenza in Chongqing, China, 2012-2018

Hum Vaccin Immunother. 2020 Jul 2;16(7):1668-1674. doi: 10.1080/21645515.2019.1693721. Epub 2020 Apr 28.

Authors

Li Qi^{1

2}, Qin Li², Xian-Bin Ding², Yuan Gao¹, Hua Ling², Tian Liu³, Yu Xiong², Kun Su², Wen-Ge Tang², Lu-Zhao Feng⁴, Qi-Yong Liu¹

Affiliations

¹ State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention , Beijing, China.
² Infectious Disease Control and Prevention Department, Chongqing Municipal Center for Disease Control and Prevention , Chongqing, China.
³ Infectious Disease Control and Prevention Department, Jingzhou Center for Disease Control and Prevention , Jingzhou City, Hubei Province, China.
⁴ Key Laboratory of Surveillance and Early-warning on Infectious Disease, Division of Infectious Disease, Chinese Center for Disease Control and Prevention , Beijing, China.

Abstract

Purpose: To estimate influenza-associated excess mortality rates (EMRs) in Chongqing from 2012 to 2018.

Methods: We obtained weekly mortality data for all-cause and four underlying causes of death (circulatory and respiratory disease (CRD), pneumonia and influenza (P&I), chronic obstructive pulmonary disease (COPD) and ischemic heart disease (IDH)), and influenza surveillance data, from 2012 to 2018. A negative-binomial regression model was used to estimate influenza-associated EMRs in two age groups (<65 years and ≥65 years).

Results: It was estimated that an annual average of 10025 influenza-associated deaths occurred in Chongqing, corresponding to 5.2% of all deaths. The average EMR for all-cause death associated with influenza was 33.5 (95% confidence interval (CI): 31.5-35.6) per 100 000 persons, and in separate cause-specific models we attributed 24.7 (95% CI: 23.3-26.0), 0.8 (95% CI: 0.7-0.8), 8.5 (95% CI: 8.1-9.0) and 5.0 (95% CI: 4.7-5.3) per 100 000 persons EMRs to CRD, P&I, COPD and IDH, respectively. The estimated EMR for influenza B virus was 20.6 (95% CI: 20.3-21.0), which was significantly higher than the rates of 5.3 (95% CI: 4.5-6.1) and 7.5 (95% CI: 6.7-8.3) for A(H3N2) and A(H1N1) pdm09 virus, respectively. The estimated EMR was 152.3 (95% CI: 136.1-168.4) for people aged ≥65 years, which was significantly higher than the rate for those aged <65 years (6.8, 95% CI: 6.3-7.2).

Conclusions: Influenza was associated with substantial EMRs in Chongqing, especially among elderly people. Influenza B virus caused a relatively higher excess mortality impact compared with A(H1N1)pdm09 and A(H3N2). It is advisable to optimize future seasonal influenza vaccine reimbursement policy in Chongqing to curb disease burden.

Keywords: Influenza; burden; excess mortality.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aged
China / epidemiology
Humans
Influenza A Virus, H1N1 Subtype*
Influenza A Virus, H3N2 Subtype
Influenza Vaccines*
Influenza, Human* / epidemiology
Seasons

Substances

Influenza Vaccines

Grants and funding

This study was supported by the High-level Medical Reserved Personnel Training Project of Chongqing, Chongqing Health Commission [grant numbers 2019GDRC014], China Postdoctoral Science Foundation [grant number 2019M660754] and the National Key R&D Program of China [grant numbers 2017YFC0907303].