Estimated Inactivation of Coronaviruses by Solar Radiation With Special Reference to COVID-19.

Abstract

Using a model developed for estimating solar inactivation of viruses of biodefense concerns, we calculated the expected inactivation of SARS‐CoV‐2 virus, cause of COVID‐19 pandemic, by artificial UVC and by solar ultraviolet radiation in several cities of the world during different times of the year. The UV sensitivity estimated here for SARS‐CoV‐2 is compared with those reported for other ssRNA viruses, including influenza A virus. The results indicate that SARS‐CoV‐2 aerosolized from infected patients and deposited on surfaces could remain infectious outdoors for considerable time during the winter in many temperate‐zone cities, with continued risk for re‐aerosolization and human infection. Conversely, the presented data indicate that SARS‐CoV‐2 should be inactivated relatively fast (faster than influenza A) during summer in many populous cities of the world, indicating that sunlight should have a role in the occurrence, spread rate and duration of coronavirus pandemics.