Does solar ultraviolet radiation play a role in COVID-19 infection and deaths? An environmental ecological study in Italy
Giancarlo Isaia, Henri Diémoz, Francesco Maluta, Ilias Fountoulakis, Daniela Ceccon, Alcide di Sarra, S. Facta, F. Fedele, Giuseppe Lorenzetto, Anna Maria Siani, Gianluca Isaia
Abstract
) between the response variables (death percentage, incidence of infections and positive tests) and biologically effective solar UV radiation, residents in nursing homes per inhabitant (NHR), air temperature, death percentage due to the most frequent comorbidities. Among all factors, the amount of solar UV radiation is the variable contributing the most to the observed correlation, explaining up to 83.2% of the variance of the COVID-19 affected cases per population. While the statistical outcomes of the study do not directly entail a specific cause-effect relationship, our results are consistent with the hypothesis that solar UV radiation impacted on the development of the infection and on its complications, e.g. through the effect of vitamin D on the immune system or virus inactivation by sunlight. The analytical framework used in this study, based on commonly available data, can be easily replicated in other countries and geographical domains to identify possible correlations between exposure to solar UV radiation and the spread of the pandemic.