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Does sunlight kill the coronavirus?

CLAIM: Since sunlight can kill the coronavirus, wearing sunblock is a bad idea during the coronavirus pandemic.

FALSE. Scientists are still studying whether ultraviolet (UV) light from the sun destroys the coronavirus. Whether it does or not, it’s important to protect your skin from the sun’s UV radiation by wearing sunscreen.

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Sunlight may destroy the novel coronavirus, but it also damages skin and can cause cancer.

There are three types of UV rays emitted by the sun—UVA, UVB, and UVC. UVC light is blocked by Earth’s atmosphere, but UVA rays and some UVB rays reach Earth’s surface.

One recent study tested whether UVB rays could affect the novel coronavirus. In order to control the environment, the study team simulated sunlight with a lamp that emitted only UVB rays and exposed surfaces to the lamp’s light. The simulated sunlight destroyed the novel coronavirus in less than 20 minutes.

More studies are needed to confirm this result, and unlike in the study, the amount of UVB light that reaches Earth’s surface is not constant—it depends on many factors, including time of day and time of year. But regardless of how quickly UVB rays may affect the coronavirus, it is important to note that the study looked at the effect on surfaces, not on people. UV radiation, which most often comes from the sun, is dangerous to people because it damages skin cells. Exposure to UV radiation is the main factor in developing skin cancer.

In other words, exposing your skin to the sun’s UV rays could destroy any coronaviruses present, but it will damage the DNA in your skin’s cells. Over time, the effects of that damage build up and make the cells more likely to develop into skin cancer.

 
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Wear sunscreen to protect your skin from the sun’s UV rays.

Sunscreen protects your skin by reducing the amount of UVB and UVA radiation that reaches the cells. For best results, use a broad-spectrum sunscreen with SPF 30 or higher, and use enough sunscreen to cover the skin thoroughly. Apply it as often as recommended on the package or at least every 2 hours. It will need to be reapplied more often after being in water, sweating, or toweling off.

Wearing protective clothing, a hat, and sunglasses also helps protect you from the sun’s UV rays. Sun protection is especially important for children because UV exposure early in life has been linked to a higher risk of skin cancer later on.

Medical experts also recommend reducing UV exposure when possible to decrease skin cancer risk. Stay inside or in the shade during mid-day, when UV rays are most intense. One rule of thumb is that if your shadow is shorter than you are, it is a high-UV time of day.

 
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Washing with soap and water removes the novel coronavirus from your skin.

You can easily remove any coronaviruses on your skin by washing with soap and water because soap bubbles break apart coronaviruses. Scrub for 20 seconds and rinse well to get the virus off your skin.

Because your hands come into contact with many surfaces each day, it’s particularly important to wash them often. Washing your hands frequently reduces the spread of germs between people and surfaces.

 

Published on: June 30, 2020