Can sunlight kill the coronavirus?
Here’s what we know. Lying in the sun or a tanning bed can lead to age spots, precancerous skin growths, and skin cancer. There’s no compelling evidence that the sun or tanning beds can kill the coronavirus in people. This is what the science shows.
UVC rays can slow the coronavirus; however, the sun's UVC rays cannot penetrate the Earth’s atmosphere. This means that you cannot get UVC rays from sunlight.
The sun emits different types of UV rays, and each affects us differently.
UVA and UVB rays: Sunlight contains both UVA and UVB rays, which reach the Earth’s surface. Overexposure to these rays can cause:
Premature skin aging, including age spots and wrinkles
Skin cancer, including melanoma, the most serious form
Tanning beds and other indoor tanning equipment also emit UVA and UVB rays. Some might even emit stronger UVA and UVB rays than those from the sun.
UVC rays: The sun also emits UVC rays, which cannot reach the Earth’s surface. The Earth’s atmosphere blocks the sun’s UVC rays.
UVC rays harm all forms of life, including the coronavirus. Since UVC rays are so harmful, workers use man-made UVC rays to disinfect hospital rooms and subway trains. While UVC machines disinfect rooms and equipment, people must stay outside the room or other area while it is being sanitized in order to stay safe.
Sunlight, tanning beds may increase your risk of coronavirus infection
While there’s no evidence that sunlight or indoor tanning can kill the coronavirus, spending time in a tanning bed or at a crowded beach, pool, or park can expose you to the coronavirus. Here’s how:
Just one infected person can spread the coronavirus to many people when people aren’t social distancing or wearing a face mask.
It’s a known fact that too much unprotected UV exposure from the sun’s UV rays can weaken your immune system. A weakened immune system makes it harder for your body to fight off a coronavirus infection.
You can pick up the coronavirus when you touch a surface, such as a tanning bed, doorknob, or reception desk, that hasn’t been disinfected. If you then touch your face, you can infect yourself.
UVC devices sold for at-home use remain untested
If you’re looking for a UVC product to disinfect your home, you’ll find plenty of options. Products include UVC wands sold to disinfect groceries and countertops.
While UVC products sold for at-home use come with claims that they’re effective against bacteria, viruses, and other germs, consumers have no idea how much UVC light, if any, a device emits. That’s a problem.
To disinfect, you need strong UVC rays. The amount of UVC needed to disinfect tends to be bright enough to damage your eyes. That’s why workers step outside a hospital room or subway train when using UVC light to disinfect.
We also know that companies have been making false claims about UVC devices for years. In 2015, the Federal Trade Commission (FTC) fined two companies for making false claims. In its advertising, one company claimed that its UVC device could kill foot fungus. The other company advertised that its device could kill E. Coli and salmonella. Neither company could prove its claim. Such claims put your health and safety at risk.
How to reduce your risk of getting the coronavirus
The Centers for Disease Control and Prevention (CDC) tells us that the best way to prevent illness is to avoid being exposed to the virus. To do this, the CDC recommends that you:
Wear a cloth face mask that covers your mouth and nose. Cloth face masks are one of the most powerful weapons we have to slow and stop the spread of the coronavirus. Wear one when you're in a public setting around people who don’t live in your household, especially when it may be difficult for you to stay six feet apart.
Social distance, which means staying at least 6 feet from others. This helps you avoid close contact with people who are sick or not part of your household.
Wash your hands often.
Cough or sneeze into a tissue or the inside of your elbow.
Clean and disinfect frequently touched surfaces, such as tables, doorknobs, and light switches.
“Clean” and “disinfect” have different meanings: To clean, according to the CDC, means you use detergent (or soap) and water to wash a dirty surface. After you clean, then you disinfect. To disinfect, use a United States Environmental Protection Agency (EPA)-registered disinfectant.
Is your disinfectant effective against the coronavirus?
To find out whether a disinfectant is effective against the coronavirus:
1. Locate the EP Reg. No. on the disinfectant.
2. Once you have this number, go to this EPA webpage and click on the link “Search by EPA registration number.”
3. Enter the product’s EPA Reg. No. in the search box. This will tell you whether the disinfectant meets the criteria set by the EPA for disinfecting the coronavirus and how long you should leave the disinfectant on the surface.
Protect your health by getting trusted information
During this time of great uncertainty, it may feel challenging to know what to do. Getting your facts from trusted sources, such as doctors and government agencies, can help.
Dermatologists want to help you protect your health and reduce your risk of skin cancer. You can do this by protecting your skin from the sun and staying out of tanning beds. Learn more about how to reduce your skin cancer risk at: Prevent skin cancer
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All content solely developed by the American Academy of Dermatology