摘要：AbstractThe outbreak of coronavirus disease 2019 (COVID‐19) showed various transmission rate (Rt) across different regions. The determination of the factors affecting transmission rate is urgent and crucial to combat COVID‐19. Here we explored variation ofRtbetween 277 regions across the globe and the associated potential socioeconomic, demographic, and environmental factors. At global scale, theRtstarted to decrease approximately 2 weeks after policy interventions initiated. This lag from the date of policy interventions initiation to the date whenRtstarted to decrease ranges from 9 to 19 days, largest in Europe and North America. We find that proportion of elderly people or life expectancy can explain ~50% of variation in transmission rate across the 277 regions. The transmission rate at the point of inflection (RI) increases by 29.4% (25.2–34.0%) for 1% uptick in the proportion of people aged above 65, indicating that elderly people face ~2.5 times higher infection risk than younger people. Air temperature is negatively correlated with transmission rate, which is mainly attributed to collinearities between air temperature and demographic factors. Our model predicted that temperature sensitivity ofRIis only −2.7% (−5.2–0%) per degree Celsius after excluding collinearities between air temperature and demographic factors. This low temperature sensitivity ofRIsuggests that a warm summer is unlikely to impede the spread of COVID‐19 naturally.Key PointsTimeline of COVID‐19 outbreak in 277 regions across the globe was summarizedProportion of elderly people or life expectancy can explain 50% of variation in transmission rate of COVID‐19 across the 277 regionsTemperature sensitivity of transmission rate at inflection point is estimated to be −2.7% (−5.2% to 0%) per degree Celsius
