UV Light: New Weapons Against Viruses

Did you know that ultraviolet (UV) light can be a powerful tool in fighting viruses? Scientists have been exploring different wavelengths of UV-C light to find safer and more environmentally friendly ways to prevent viral infections. For example, far-UV-C radiation with a wavelength of 233 nm can kill viruses on the skin's outer layer without harming deeper skin layers. This makes it a potential new method for treating skin infections. For disinfecting rooms, 275 nm UV-C LED lamps could be a better choice. Unlike traditional mercury vapor lamps, which are harmful to both people and the environment, these LED lamps avoid the use of toxic mercury.Researchers tested how well different UV-C wavelengths inactivate viruses. They used a test with multiple viruses on various surfaces like stainless steel, PVC, and glass. They found that the amount of UV-C radiation needed to kill viruses depends on the type of virus. Enveloped viruses, which have a protective layer, are easier to kill than non-enveloped viruses. UV-C radiation at 233 nm can inactivate viruses at a dose of 80 mJ/cm². For a 4-log inactivation at 275 nm, the dose required varies. Enveloped viruses need up to 70 mJ/cm², while non-enveloped viruses need a maximum of 600 mJ/cm². This means that higher radiation doses are needed at 275 nm compared to the traditional 254 nm. So, 275 nm LED emitters could be a greener alternative to old mercury vapor lamps. And 233 nm radiation might be a useful addition to our arsenal against viruses, especially for treating skin infections.