Contribution of Temperature Increase to Restrain the Transmission of COVID-19

Abstract COVID-19 outbreak has already become a global pandemic and containing this rapid worldwide transmission is of great challenge. The impacts of temperature and humidity on the COVID-19 transmission rate are still under discussion. Here, we elucidated these relationships by utilizing two unique scenarios, repeated measurement and natural experiment, using the COVID-19 cases reported from Jan. 23–Feb. 21, 2020, in China. The modeling results revealed that higher temperature was most strongly associated with decreased COVID-19 transmission at lag time of 8 days. Relative humidity (RH) appeared to have only a slight effect. These findings were verified by assessing SARS-CoV-2 infectivity under the relevant conditions of temperature (4–37°C) and RH (> 40%). We concluded that temperature increase made an important, but not determined, contribution to restraining the COVID-19 outbreak in China. It suggested that the emphasis of other effective controlling polices should be strictly implemented to restrain COVID-19 transmission for the cold seasons.