Italian scientists develop model to show how solar radiation can kill the coronavirus
- Outbreaks of Covid-19 appear to have been less severe in southern parts of the world where the intensity of ultraviolet light is higher, study says
- But scientists face many challenges establishing a link between solar radiation and spread of disease, Chinese astronomer says
As well as the better known UVA and UVB forms of ultraviolet light, solar radiation contains UVC, which has a shorter, more energetic wavelength that is powerful enough to break up genetic material. Thankfully for humans, most UVC is filtered out by the ozone layer.
However, a team of researchers from the National Institute for Astrophysics in Rome, led by Dr Fabrizio Nicastro, calculated a dose of UVA and UVB radiation capable of causing the same damage to the coronavirus as an equivalent blast of UVC.
They then built a model to estimate how long it would take to kill the virus in more than 100 countries.
The results varied, but generally, from January to April in countries between 40 to 60 degrees north of the equator, exposure to the UV light for between 30 minutes and 14 hours a day was required to kill 63 per cent of the pathogen.