No association of COVID-19 transmission with temperature or UV radiation in Chinese cities

Temperature and ultraviolet spreadability of coronavirus disease 2019. a) Cumulative incidence rate and basic reproduction number (R₀) hold no significant association with the temperature in cities outside and inside Hubei. Relative humidity and ultraviolet effects have been adjusted in the model. b) Cumulative incidence rate and R₀ hold no significant associations with ultraviolet in cities outside and inside Hubei. Temperature and relative humidity effects have been adjusted in the model. Solid and dashed lines refer to the linear trend of the correlation of the cumulative incidence rate or basic reproductive number and environmental factors in cities outside Hubei (solid lines) and inside Hubei (dashed lines).