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Working From Home? Read ‘Dr. Germ’s’ Tips on Ridding Your House of COVID-19 and Other Germs

March 22nd, 2020
James Tehrani
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Remote working situations are nothing new, but the sheer number of people working remotely because of the COVID-19 virus is undoubtedly unprecedented.

To learn more about how people can slow the spread of the virus in their homes and in the office, Spark caught up with Dr. Chuck Gerba, who is a professor of environmental science at the University of Arizona as well as a professor of microbiology and immunology. “Dr. Germ,” as he is known, has spent his career tracking and learning about the spread of viruses and bacteria among other germ types.

If you’re a germaphobe, you’ll be happy to know there are people out there like Gerba germinating on how best to keep people safe and healthy from viruses. But if you’re a germaphobe, some of his observations might cause copious consternation. He told CNN last year, for instance, that “There’s more fecal bacteria in your kitchen sink than there is in a toilet after you flush it. That’s why your dog drinks out of the toilet. He’s smarter than you think.”

Doggone, right.

Dr. Chuck Gerba
Chuck Gerba podcast
Listen to the full interview on the SpheraNOW podcast.

Spark: So, obviously there’s a lot of concerns, and there’s a lot of information and misinformation out there about this coronavirus, COVID-19, so what are your biggest concerns at this time?

Chuck Gerba: Well, I’m concerned that there might be misinformation out there. Actually, a lot is known about the spread of viruses, respiratory viruses, like this virus or other coronaviruses. Most people don’t realize that coronaviruses cause about 5% to 7% of the common colds every year in the United States, but they don’t cause any mortality. We do know at least the basics of how coronavirus is spread through the environment and their survival and their seasonality. We’re hoping that this new coronavirus follows the same pattern so that we can better predict people’s exposures to the virus and control their exposures.

Spark: Sure. And so what exactly is the difference between this one versus, for example, when SARS happened in 2002? Is social media the difference here that there’s just more information out there?

Chuck Gerba: No, I think the new coronavirus is behaving much more like an influenza, and the more common coronaviruses that cause the colds, and that rather than SARS or MERS, which was the Middle East respiratory [syndrome]. The SARS virus particularly didn’t survive well in the environment. So, we’re seeing a virus [with COVID-19] that is more typical of respiratory viruses in the wintertime than we did with the SARS virus. You had to be fairly close to an individual to get the SARS virus. This new coronavirus seems to be able to persist maybe a longer time in aerosols, and on surfaces which is more conducive to its transmission.

Spark: So, obviously there are a lot of people who are working from home, and there are a lot of students who are home these days. So, just for people who are around the house, what are some of the areas that are most concerning to you in terms of spreading this virus that maybe need to be cleaned more than others?

Chuck Gerba: Yeah, we’ve done a number of studies on how viruses spread in households, on surfaces in particular, and how to control it. Probably the best strategy, let me say right away, is when you’re in a home, wash your hands or use a hand sanitizer as soon as you come home so you avoid spreading the virus around the home. We’ve seen if a person has a virus on their hands it will eventually in a household of four contaminate about 90% of the surfaces within about four hours. And those—


Timely Tips From Dr. Gerba:


Spark: 90%?

Chuck Gerba: Ninety percent because, of the activity of people moving around a household, you’re really touching more surfaces than you think in a household. The other control point, usually where we find a lot of the viruses is on tabletops, countertops, surfaces, because that’s where your hands are all the time, or high touch areas like the refrigerator door handle for example, and in the bathroom area it tends to be the taps and the bar of soap. And then you get the virus on cloth towels, which tend to be reused. So that helps spread the virus around a household, too. That’s why, if you can, try to use a liquid hand soap. That’s why you don’t see bar soap in public places because bar soap is believed to play a role in potentially transmitting microorganisms. And if you’re using towels to dry your hands, cloth towels, don’t share them among individuals, and try to wash them every two to three days in hot water, and dry for at least 45 minutes because they tend to accumulate organisms because they stay wet and moist. So, even bacteria will grow in towels because of the moisture in that.

Spark: Do you recommend people use paper towels instead?

Chuck Gerba: Yeah, if you can, I would use a paper towel, and then you throw it away. The same thing if you’re cleaning your house, try to use disinfecting wipes because then you throw it away. If you use a spray and wipe, make sure you read the instructions on the disinfectant. Usually for most common ones used in a household, you have to wait two to 10 minutes, so spray the surface, wait the amount of time it says on the bottle on the disinfectant, and then wipe it up. Most people just spray, and wipe it up right away, and that that’s not as effective. … Now if you have bleach, usually 30 seconds is all you need with bleach. It’s a very rapid-acting disinfectant. Unfortunately, it’s more damaging to surfaces.

Spark: I was going to ask you though, obviously there’s a shortage of disinfectant wipes out there. A lot of people are buying them up, so what would be an alternative that people can use that they might already have in their household?

Chuck Gerba: Well, bleach would be your first alternative. Any bleach that you might have in your household you might use for laundry purposes, for example, that can be diluted to use in the home. So, that’s one of your first substitutes that you could use. Spray, and wipe disinfectants will work, oftentimes, read the label if it usually has bleach in it. A lot of spray products might have bleach, or even some bleach substitutes like used in laundry can be used, potentially, they contain a nonbleach disinfectant, actually, that can be used. They’re not usually advertised for that purpose or registered for that purpose, but in our studies, things that contain oxidizing chemicals like potassium perborate, like Clorox 2.

Spark: And for the people who are still going into work, and obviously not every workplace is closed, what can companies do to help prevent the spread of viruses?

Chuck Gerba: Well, we’ve done studies in office buildings on how viruses spread. We’ve put virus tracers on push plates and doorknobs to office buildings of about 80 people, and within four hours, about half the people had the virus on their hand in that building. … We’ve found that risk of that spread can be reduced by 80%, or more, if you provide your employees with hand sanitizers, and disinfecting wipes at work quite well. In the coffee break room, I’d recommend a hand sanitizer dispenser. That worked very well in our studies. Usually janitorial crews, or custodial crews will have a lot of these disinfectants. I think one thing to emphasize, too, is what we’ve learned is the coffee break rooms and conference rooms, the tabletops should really be disinfected if nothing else by the custodial crews, might be a couple of times per day, because that seemed to do a lot in reducing the spread of the viruses in an office building.

Spark: Can you tell me a little bit about virus tracers? How does that work?

Chuck Gerba: What we’ve done is used bacterial viruses, which don’t affect the human beings or animals, and they don’t cause illness unlike a push plate to a building. And then we’ll come back four hours later, and test the surfaces like tabletops, desktops, phones in people’s hands, and see how that virus spread. So, usually both in the home, at home was more effective—because I think it’s smaller area if you have children who are very active—within four hours, over half the surfaces are usually contaminated. Now, we’ve gone in and repeated those experiments, but giving people hand sanitizers, and disinfecting wipes, and we’ve found, at least in an office building, you have reduced your probability of getting influenza by 80% if you actually use those types of products.

Spark: What are your thoughts on the efforts so far to flatten the curve? Do you feel like we’re in the right direction with the steps that have already been taken?

Chuck Gerba: Yeah, I think the steps that have been taken, staying home, social separation of individuals, that will go a long way. It seemed to work in China, so it’s hopefully that the same strategy will work here in the United States and in other countries.

Spark: Is there any other information that you think would be helpful for people to know about dealing with this situation now?

Chuck Gerba: I think one of the things that may be most useful is trying to concentrate on hands, and disinfecting key surfaces without really overdoing it. In our studies with hand sanitizers, one to three times a day seems to be adequate, and only be strategic about it. If you’re going out somewhere and coming back, wash your hands, or use a hand sanitizer, and try to keep your social distances like I said. I mean, those are really the things that we know work.

James Tehrani

James Tehrani is an award-winning writer and editor based in Chicago. He is the editor-in-chief of Spark.

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