OBJECTIVES: Seasonal influenza causes substantial morbidity and mortality. The coverage rate of influenza vaccination in China is low at approximately 2%. Estimation of the national costs is vital to inform the public policy for setting interventions priorities under the ongoing covid-19 pandemic. We assessed the annual economic burden of influenza in mainland China for 2011–2019.

METHODS: The economic burden was estimated using micro-costing method by multiplying the resource quantity by unit costs from a societal perspective. The time horizon of study was an influenza seasonal year. An extensive search of published literature in English and Chinese was performed on epidemiological parameters (including influenza incidence, self-medication rate, outpatient rate, inpatient rate, influenza death rate) and related indirect costs for 2011–2019. Direct medical costs, and direct non-medical costs are obtained from the reimbursement data from 5 representative cities. Meta-analysis was used to calculate the final input with lower and upper bound of each parameter to consider annual variation.

RESULTS: Influenza has resulted in 109,856,560 (range: 84,429,967–144,740,205) cases, 1,087,983 (770,953–1,558,579) hospitalizations, and 114,462 (105,000–125,000) death annually during 2011–2019. Annual economic burden associated with seasonal influenza was $8,905,629,809 ($4,748,580,740–$15,276,489,525), accounting for 0.06% of the 2019 GDP in China. Key cost driver was the self-medication costs (nearly half of the ILI patients sought self-medication in China), making up 38.88% of total costs, followed by inpatient costs (34.13% of total costs).

CONCLUSIONS: The economic burden of seasonal influenza in China is significant from the societal perspective, especially for young children and older people. The influenza vaccination coverage rate is exceptionally low in China. Given that vaccination is the most effective prevention strategy, our estimates highlight an opportunity to enhance the influenza vaccination program and public health policy.