- Sunlight is linked to a lower incidence of Covid-19-related deaths
- The study measured the relationship between UVA and Covid-19 deaths in three countries
- Researchers say that sunlight could be considered as a treatment for Covid-19
Exposure to ambient Ultraviolet A (UVA) radiation is associated with lower Covid-19-related mortality, a new study has found.
The research published in the British Journal of Dermatology examined the relationship between sunlight and Covid-19 deaths.
Looking at Covid-19-related deaths
Researchers pooled recorded deaths from Covid-19 in the continental US from January to April 2020 with UV levels for 2 474 US counties for the same period.
They also looked at records of Covid-19 deaths between 1 March to 17 April 2020 in the United Kingdom and estimated the number of excess deaths in Italy based on figures from the Italian Institute of Statistics for 1 March to 30 April for 2015 to 2019 compared to 2020.
Then scientists derived the mean daily UVA for the areas in each study: USA (1 January to 30 April), England (1 January to 17 April), and Italy (1 January to 30 April).
They then observed the UVA levels just before the period during which they recorded deaths, based on the lag between Covid-19 infection and death.
The researchers took into account factors associated with increased exposure to the virus and risk of death, such as age, ethnicity, socioeconomic status, population density, air pollution, temperature and levels of infection in local areas.
Sunlight is key
The findings of the study show that people who live in areas with the highest exposure to UVA rays had a lower risk of dying from Covid-19 than those with lower exposure to UVA.
The study also found that sun exposure may also reduce death from Covid-19 due to factors unrelated to vitamin D.
"Our models are consistent with a situation where UVA exposure may be an additional UV protective factor against Covid-19, along with other potential UV related pathways through vitamin D production and direct viricidal suppression," the paper reads.
Researchers added that optimising sun exposure may be an effective public health intervention against Covid-19.