How to Disinfect Surfaces of the COVID-19 Virus

We know coronavirus disease 2019 (COVID-19) mainly spreads from person to person by respiratory droplets that are ejected when an infected person coughs, sneezes or talks—hence the guideline to stay at least 6 feet from people outside your household.

The virus also is spread on surfaces that become contaminated with these droplets. That’s why it’s important to keep high-touch surfaces such as doorknobs, kitchen counters and sink handles disinfected and why grocery stores have a hard time keeping household cleaners in stock.

But, how do you know which cleaner to use and what steps to take to ensure you are disinfecting correctly? Emily Sickbert-Bennett, PhD, director of UNC Medical Center Infection Prevention, answers these questions.

What ingredients should your household cleaner have to be effective in killing the coronavirus?

The good news is that coronaviruses, including COVID-19, are “some of the easiest germs to kill and are less hardy in the environment,” says Dr. Sickbert-Bennett. “Disinfection is very effective against coronaviruses.”

The key ingredient you need to disinfect against COVID-19—or any virus—is an antimicrobial agent. This is a substance that kills microorganisms or stops their growth. (In this case, the microorganism is the virus.) In household cleaners, common antimicrobial agents are either chlorine bleach or quaternary ammonium compounds. You want to look for these words on the label: “EPA Registration Number” or “Active Ingredient.”

“If a product does not have an antimicrobial agent listed, then it’s a natural cleaner,” Dr. Sickbert-Bennett says. “Natural cleaners might be effective just for removing scum and grime, but not for actually killing any germs that could be on surfaces.”

What’s the best method to use to disinfect a surface?

The answer depends on the product you’re using. Follow the directions on the container. Know that each disinfectant has its own contact time, which is the time the chemical needs to stay in contact with the surface to effectively kill the germs on that surface, Dr. Sickbert-Bennett says.

Some disinfectants have contact times as short as one minute and others as long as 10 minutes.

“And that’s not the time you take physically moving the product across the surface, but the time it should be left undisturbed,” Dr. Sickbert-Bennett says. “So if it’s your practice to spray down the counter and then come with a wet cloth behind it and wipe all that disinfectant off, then it really hasn’t contacted the surface for the time needed.”

Spray your disinfectant and leave it undisturbed on the surface for the amount of time recommended. Or make it simpler with a disinfectant wipe.

“Then, you can just wipe down the surface and leave it alone,” Dr. Sickbert-Bennett says. “It’s a one-step process.”

How often should you disinfect high-touch surfaces?

High-touch surfaces include doorknobs, cabinet handles, sink faucets, light switches, tables, chairs, countertops, phones, keyboards and TV remote controls. The number of times you need to clean those depends on how often they are re-contaminated.

“Surfaces can become re-contaminated in an instant if they’re touched by a contaminated hand,” Dr. Sickbert-Bennett says.

That’s why it’s vital to practice good hand hygiene.

“Your hands are the mechanism that would bring any germs from surfaces to your face (and into your body). And so the hands are really the vehicle that you need to think about,” she says.

Washing your hands with soap for 20 seconds kills the virus that causes COVID-19. Therefore, even if the virus is on a surface you touch, as long as you thoroughly wash your hands after you touched it, you’ve killed and eliminated the virus. Just be careful not to touch your face or any other surface before you wash.

It’s important to wash your hands as soon as you come home from running errands or other activities in public, Dr. Sickbert-Bennett says.

What’s the best type of cloth to use with your disinfectant?

Microfiber cloths have an electrostatic charge, which means they can pick up germs better than other types of cloth.

“Just be cognizant of how often you’re reusing that microfiber cloth and when it’s time to launder it,” Dr. Sickbert-Bennett says.

Also, be mindful of the order in which you disinfect surfaces.

“Start cleaning an area that’s cleanest first, and work from clean to dirty,” Dr. Sickbert-Bennett says. “So you don’t want to scrub the bottom of your sink basin and then wipe down your countertops after that.”

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