Does UV light kill the new coronavirus?
Ultraviolet light has been used to stop pathogens in their tracks for decades. But does it work against SARS-CoV-2, the virus behind the pandemic?
The short answer is yes. But it takes the right kind of UV in the right dosage, a complex operation that is best administered by trained professionals. In other words, many at-home UV-light devices claiming to kill SARS-CoV-2 likely aren't a safe bet.
UV radiation can be classified into three types based on wavelength: UVA, UVB and UVC. Nearly all the UV radiation that reaches Earth is UVA, because most of UVB and all of UVC light is absorbed by the ozone layer, according to the Centers for Disease Control and Prevention. And it's UVC, which has the shortest wavelength and the highest energy, that can act as a disinfectant.
Related: What is ultraviolet light?
"UVC has been used for years, it's not new," Indermeet Kohli, a physicist who studies photomedicine in dermatology at Henry Ford Hospital in Detroit, told Live Science. UVC at a specific wavelength, 254 nanometers, has been successfully used to inactivate H1N1 influenza and other coronaviruses, such as severe acute respiratory virus (SARS-CoV) and Middle Eastern Respiratory Syndrome (MERS-CoV), she said. A study published June 26 to the preprint database medRxiv from Kohli's colleagues awaiting peer review now confirms that UVC also eliminates SARS-CoV-2.
UVC-254 works because this wavelength causes lesions in DNA and RNA. Enough exposure to UVC-254 damages the DNA and RNA so that they can't replicate, effectively killing or inactivating a microorganism or virus.
"The data that backs up this technology, the ease of use, and the non-contact nature" of UVC make it a valuable tool amid the pandemic, Kohli said. But responsible, accurate use is critical. UVC's DNA-damaging capabilities make it extremely dangerous to human skin and eyes, Kohli said. She cautioned that UVC disinfection technologies should primarily be left to medical facilities and evaluated for safety and efficacy by teams with expertise in photomedicine and photobiology.
When it comes to a-home UVC lamps, their ability to damage skin and eyes isn't the only danger, Dr. Jacob Scott, a research physician in the Department of Translational Hematology and Oncology Research at Cleveland Clinic, said. These devices also have low quality control, which means there's no guarantee that you're actually eliminating the pathogen, he said.
"UVC does kill the virus, period, but the issue is you have to get enough dose," Scott told Live Science. "Particularly, for N95 masks, which are porous, it takes a pretty big dose" of UVC-254 nm to eliminate SARS-CoV-2. This kind of accuracy isn't possible with at-home devices.
In hospitals, the geometry of the room, shadowing, timing and the type of material or object being disinfected are all accounted for when experts determine the right dosage of UVC needed to kill pathogens. But that kind of "quality assurance is really hard out in the world, out in the wild," Scott said. At-home devices don't offer that kind of precision, so using them could offer a false assurance that SARS-CoV-2 has been eliminated when it hasn't, he noted. "Having something you think is clean, but it's not, is worse than something that you know is dirty" because it affects your behavior toward that object, he said.
Both Kohli and Scott and their teams are working to make UVC disinfection of personal protective equipment (PPE), such as face masks and N95 respirators, more efficient. Kohli's group advises hospitals and vendors repurposing existing UVC equipment for N95 respirator decontamination. Scott's group developed a machine that can be used by smaller medical facilities and a software program that helps users factor in the geometry of the disinfection room so that staff can deliver the most effective dose of UVC.
There are ongoing conversations in the field about installing UVC units in ceilings to decontaminate circulating air, Kohli said. And others are researching another wavelength of UVC called UVC-222 or Far-UVC, which may not damage human cells, she added. But that will require more research, Kohli said. Still, it's clear that "used accurately and responsibly, UVC has enormous potential."
Originally published on Live Science.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Donavyn Coffey is a Kentucky-based health and environment journalist reporting on healthcare, food systems and anything you can CRISPR. Her work has appeared in Scientific American, Wired UK, Popular Science and Youth Today, among others. Donavyn was a Fulbright Fellow to Denmark where she studied molecular nutrition and food policy. She holds a bachelor's degree in biotechnology from the University of Kentucky and master's degrees in food technology from Aarhus University and journalism from New York University.
This needs re-wording for clarity; H1N1 isn't a coronavirus; no influenza is.
Another thought about this coronavirus situation. It's a fact that this coronavirus molecule will sit in the air for a while where it can travel around and maybe infect someone else. Well why don't we use some kind of sticky stuff to capture the virus as it travels around areas that we are. If we put in large sticky pads of something inside of something and have air blow on it then the viruses and germs should stick to the sticky stuff. No virus or germ can get away from getting stuck! Add some disinfectant stuff or something else that could help the sticky stuff kill the coronavirus and other viruses and germs. Add these sticky pads to the laser treated copper stuff I talked about earlier and we may end up with a contraption that will surely kill a simple thing as a moist molecule laced with some killer ability called the coronavirus. Surely we should be smart enough to kill a molecule floating in the air? Aren't we?
Being that laser treated copper can kill the coronavirus under certain circumstances don't you think that we should set up the circumstances in which things are happening that are causing the laser treated copper to actually kill the virus! The scientist that discovered this said that the laser treated copper surface had a hard time killing the virus because of the coronavirus itself was too small for the laser treated copper to kill it. But what if we were to have a new kind of fan made of of multiple strands of laser treated copper wire that has 3 sharp U shape sharp twisted ridges that are attached to a 1-5 feet fast turning fan pole. Then put a laser treated copper plague of whatever size you need in front of the fans in the air vents and hallways and wherever else you have them. The fans fast moving air current will cause the Coronavirus to slam into the laser treated copper plague and shred apart also. Have this device in the vent shafts and hallways and corridors and E.R. rooms and all hospitals and nursing homes and offices and stores and in homes, rooms and areas where the sick are and where we live and work. Add some ultra-violet light to the fan and we will then have a way to stop or drastically slow the transmission of the Coronavirus! This fan must be the new kind of fan that will help us all stop this Coronavirus!
The brain is a biological computer that can manufacture all of us and every living thing on Earth. Each species has a unique brain that takes the food the we give ourselves and makes us whatever we may be biologically programed to be. If the human body needs 9 different amino acids to create all the different kinds of cells that the body needs to make us then why not give the body the 9 different amino acids in every day meals to ourselves and see what happens because then that biological computer in our minds can then maybe have the cure for fighting the coronavirus and all it needed was the combination of all those 9 amino acids in our food daily to make the cells to overtake the damage that the coronavirus can cause. There is a recipe for a food dish called Adelynn's Miracle Beans recipe that has all the 9 different amino acids as well as many other nutrients the body needs. Perhaps if we were to give those that are sick from coronavirus 2 servings of this Adelynn's Miracle Beans recipe daily 5-6 hours apart and also give 2 Centrum equivalent vitamins with a bean meal 5-6 hours apart. This will give one's body all the proteins, vitamins and minerals that a human body needs to create any kind of blood cell. Maybe the human body will figure out a way to kill the coronavirus as well as other flues and colds if we give it the ingredients for it to do so! Someone try it. It beats dying or suffering from the illness. I know that taking 2 Centrum equivalent in one day with a meal 5 hours apart does help one get rid of the flu and colds because I have been doing it for 25 years and it always help me stop getting sicker every time I felt like I was getting the flu. So maybe eating Adelynn's Miracle Beans and taking the vitamins will help make people with the coronavirus get better.
The entire thrust of the article was how UVA and UVB are useless against virus, period. And it further points out how UVC kills not only virus but also destroys all DNA by unraveling the strands. This destroys ALL life, including the virus.
This aspect is where the sarcasm should start. Our appointed president thinks having a UVC ray eating its way to an infected persons lungs, destroying all in its path, is a solution.
Surely that can be made to sound humorous. Is not any death not our own funny? Is Trump wrong on that also?
Sorry for the cold water and sourness, I have lost most of my sense of humor with the deaths passing 135,000 today and 500,000 beginning to look like the lowest number of unnecessary dead expected under current policy.
"No laughs left 'cause we laughed them all, in a very short time"
What he failed to do was have all travelers quarantined and tested BEFORE they set foot on US soil.
And before you say why didn't the governors do this, well, it works best when it's a policy coming from the Federal government. One or two governors doing this isn't going to work if others do nothing. The virus WILL get in without a UNIFIED plan.
And will state that COVID19 was caused by the 90's scientists and activists (disguised terrorists) that saved the O3 layer...
Of course... if COVID19 was not a Chinese hoax supported by the WHO...