Disease burden of seasonal influenza in China from 2010 to 2019: A systematic review and meta-analysis based on multiple indicators

Through systematic review and meta-analysis, the average annual disease burden of seasonal influenza in China from 2010 to 2019 was estimated, and the differences between the northern and the southern regions were compared. A systematic review was conducted to collect articles from 2010 to 2019 on the disease burden of seasonal influenza in China. Study quality was assessed using the cross-sectional appraisal tool from the Agency for Healthcare Research and Quality. Relevant data were extracted, and a random-effects model was used to produce age-stratified estimates for each metric. From these, the average annual number of influenza cases and excess deaths were calculated. A subgroup analysis compared northern and southern regions to account for possible regional differences. All statistical analyses were conducted using R software. A total of 24 articles were included. The annual average number of influenza cases is 111,429,687 (95%CI: 82,372,516-154,937,609). The burden of influenza, in terms of incidence rates, outpatient rates, and hospitalization rates, was heaviest among children under 5 years old. The burden of excess mortality was the heaviest among the elderly ≥65years old. Except for the incidence rates and hospitalization rates of individual age groups, there were no significant north-south differences in most epidemiological indicators. The study obtains the average annual disease burden of seasonal influenza. The disease burden of children <5years old and the elderly is relatively heavier. The study provides valuable evidence for the prevention and control of seasonal influenza.