Nonpharmaceutical Interventions Used to Control COVID-19 Reduced Seasonal Influenza Transmission in China

Abstract

To suppress the ongoing COVID-19 pandemic, the Chinese government has implemented nonpharmaceutical interventions (NPIs). Because COVID-19 and influenza have similar means of transmission, NPIs targeting COVID-19 may also affect influenza transmission. In this study, the extent to which NPIs targeting COVID-19 have affected seasonal influenza transmission was explored. Indicators of seasonal influenza activity in the epidemiological year 2019-2020 were compared with those in 2017-2018 and 2018-2019. The incidence rate of seasonal influenza reduced by 64% in 2019-2020 (P < .001). These findings suggest that NPIs aimed at controlling COVID-19 significantly reduced seasonal influenza transmission in China.