The seasonality of COVID-19 has been a mystery since the disease first emerged one year ago, though there have been some clues that UV could play a role. The researchers diagnosed the relationship between UV and COVID-19 using data from the beginning of the pandemic and then used that relationship to simulate how seasonal changes might influence the spread of COVID-19. While this research shows that COVID-19 exhibits a seasonal pattern due to changes in UV, the full seasonality of COVID-19 remains unclear because of uncertain influences from other environmental factors such as temperature and humidity. It is even possible that UV reduces susceptibility to COVID-19 by stimulating production of vitamin D and boosting the immune system. “But a better understanding of the environmental influences on COVID-19 could allow for seasonal adjustment of containment policies and may help inform vaccination strategies.
