As society hunkers down in an attempt to stop the spread of COVID-19, commonly known as the coronavirus, people are taking stringent precautions to keep themselves from catching the disease, including self-quarantining and disinfecting commonly touched surfaces. As such, hand sanitizer, rubbing alcohol, and other disinfectants are currently in short supply.

With man-made sanitizers in limited supply, many are turning to nature’s disinfectant: ultraviolet light. UV irradiation has long been used to sterilize objects and rooms, so it makes sense to wonder: Can UV light kill coronavirus?


If you’ve ever gotten a sunburn, you’ve had a taste of how UV light kills viruses: UV light can damage DNA. A DNA molecule is made of two strands bound together by four bases, adenine (A), cytosine (C), guanine (G), and thymine (T). These bases are like an alphabet, and their sequence forms instructions for cells to reproduce.


UV light can cause thymine bases to fuse together, scrambling the DNA sequence and essentially throwing a wrench into the machinery. Since the DNA sequence is no longer correct, it can no longer replicate properly. This is how UV light annihilates viruses, by destroying their ability to reproduce.


COVID-19 is a new breed, and as such there is a dearth of studies on its resistance to UV. That hasn’t stopped people from rolling out UV devices to thwart the virus, however. Companies that produce UV devices are seeing a notable boost in sales, and hospitals are using UV-equipped robots to disinfect hospital rooms; even face masks are getting the UV treatment