University of Edinburgh in the UK found that in the regions with a large number of sunlight, a smaller number of deaths are observed due to COVID-19. At the same time, a certain subtype of ultraviolet light was the potential protection against coronavirus. This is reported in the article published in the British Journal of Dermatology magazine.
Researchers have compared all registered deaths from complications caused by coronavirus infection, in the continental part of the United States from January to April 2020 with ultraviolet levels in 2474 US districts for the same period. As a result, it turned out that people living in areas with the highest impact of ultraviolet A (UVA), which constitutes 95 percent of solar UV radiation, had a lower risk of death from COVID-19 compared to people living in places with lower levels UVA. The analysis was repeated in England and Italy with the same results.
Scientists took into account such third-party factors of high risk of disease and death as age, ethnicity, socio-economic status, population density, air pollution, temperature and infection levels in certain areas. At the same time, the effect cannot be explained by a higher level of vitamin D in the body, since its development is influenced by ultraviolet in (UVB), and the study covered areas with insufficient UVB levels for this.
One of the possible explanations, the effect of sunlight causes the skin to select nitrogen oxide, which, as shown in some studies, reduces the ability of the virus to replication. However, due to the fact that the new scientific work was a observative (and not controlled test), the exact cause and effect on the results obtained should not be determined yet.