Tegan Taylor: Hello, here is Coronacast, a podcast all about the coronavirus where we answer your questions. I’m a reporter for ABC Health Tegan Taylor.
Norman Swan: And I’m a doctor and journalist, Dr. Norman Swan, presenter of the ABC Health Report on National Radio.
Tegan Taylor: So, Norman, everyone has been really good at staying at home as much as possible, but one of the few things we can do during this time of social distancing is to go out to the supermarket. So it’s not surprising that we get a lot of questions about how to stay safe in stores. So we decided to do an entire episode on this today.
Norman Swan: Yes, because it’s our whole world, the supermarket.
Tegan Taylor: That is true!
Norman Swan: So where do we start, Tegan?
Tegan Taylor: Let’s start with social distancing in stores. How far should we stay away from other buyers when we are in the supermarket?
Norman Swan: The rule for supermarkets is the same as everywhere else. You really have to maintain a difference of about two meters, about six feet from other people and you just have to be tempted not to rush towards them, stay back and think about it well and step back if other people bother you don’t get angry, just walk away. Social distancing is really important.
Tegan Taylor: What about the staff? You sometimes have to stand a little closer than six feet from staff, and should they also wear masks and gloves and that sort of thing?
Norman Swan: We get a lot of questions about the staff. So there are two elements to the staff, one is the people at the checkouts, and more and more in the supermarkets, you see these screens in Perspex, which prevent customers from transmitting their droplets to the staff and the staff from you their droplets, so you would assume that they are quite effective.
And the staff who serve the shelves, there are not many advantages to gloves, we have already talked about this. Gloves can give you a feeling of invulnerability when in fact it is not deserved because if you touch a surface with gloves infected with a coronavirus, the gloves will be infected and you can transmit it to something else. It is therefore almost certainly better not to wear gloves in this situation and to wash your hands regularly before and after touching objects. This means that staff must use a hand sanitizer a lot.
The masks are controversial. The main reason for wearing masks in a supermarket environment is that if you are asymptomatic, you are less likely to pass it on to other people. So it will be the policy of the supermarket or the person involved. It probably won’t make a huge difference, but if you choose to wear a mask, it will help.
Tegan Taylor: You mentioned shelves before, people stacking shelves and stuff, what are the odds for me as a buyer to buy a coronavirus from a product that is on a supermarket shelf?
Norman Swan: You are much more likely to get coronavirus by approaching someone who coughs, sneezes, or exhales the virus from droplets in the air rather than on surfaces. We’ve talked a lot about surfaces and you can get them from surfaces, but the reality is that the situation is less risky than just general contact with someone and sharing the air they breathe. It sounds disgusting, but it’s like that. So the products from the shelves, the risk is low, and simply if you observe hand hygiene, you remove the products from the shelves, you put them in the cart, then you wash your hands or you use a disinfectant to hands, so it’s a pretty safe place to be. And most of the products on the shelves that you’re going to buy are cardboard or paper, and the coronavirus doesn’t last long, up to a day, but it decreases quite quickly. The products on the shelves are pretty safe, they’re not entirely safe, but if you’re just careful with hand hygiene, don’t touch your face when shopping, it’ll keep you pretty well protected.
Tegan Taylor: This actually leads very well to Jim’s next question. He is 80 years old, so he is obviously in this older age group, possibly at higher risk of having poor results if he contracts a coronavirus. He registered on the priority list for home deliveries, they will stay on the porch. He wonders if he shouldn’t try to sterilize items. He has a hand sterilizer and an alcohol spray. Should he water his groceries before bringing them inside?
Norman Swan: I think, again, it’s kind of like the shopping situation where, to be really careful, you might just want to leave the outside packaging outside and take in the products themselves, even if it can be a little more laborious. And once you’ve done that, it wouldn’t do any harm with plastic or steel, these hard surfaces, to spray it with isopropyl alcohol if you have it. It is a way of securing the situation for yourself. If you want to get rid of the packaging itself, it would be safe enough to go outside, put it in the trash, and then wash your hands with soap and water afterwards. And again, after handling the products, soap and water then just on your hands to make sure you protect yourself.
Tegan Taylor: Tricia asks us how to keep surfaces clean, especially at home, what is the best concentration for a bleach solution or if you simply have to lather everything in soaps. What do we know?
Norman Swan: I think there is no doubt that the safest and easiest thing to use for surfaces is detergent. The detergent gets rid of this virus because it removes the fat around the virus and exposes it and the virus dies. So it’s the most effective thing. You can go to bleach and peroxide, but the problem with bleach is that you then need to reach the right concentration of sodium hypochlorite which is the active chemical in bleach, and the concentration is 0.1%. Not 1% but 0.1%. And you’d better googgle a calculator for diluting bleach, because inevitably, if I tell you how to dilute it, it will be bad and you will make a mistake. But the key message here with bleach is that if you dilute it yourself to 0.1%, you have to be very careful and not add any other chemicals other than bleach. But the detergent works well, so why worry about bleach is really what I think.
Tegan Taylor: What about washing other things, fruits and vegetables, should we use detergent for this? Can you use hot water, should you use cold water? Help us!
Norman Swan: If only we really knew the answer to this question.
Tegan Taylor: Exactly.
Norman Swan: I think most people say that the risk of fruits and vegetables is low and that you should wash it as you normally would, which is in cold water, thoroughly, and dry it as you normally would. It will be fine. And the reality is that by the time you get home, these organic surfaces, the virus may not survive as long on them. And so the key here is to wash as you normally would, the risk is extremely low, and you’re much better off having fresh fruits and vegetables than the small risk of catching the coronavirus from them.
Tegan Taylor: The questions get thick and fast. I have hot and cold questions for you. So, first of all …
Norman Swan: Let’s go hot.
Tegan Taylor: Let’s go hot first. Does boiling water kill the virus? If you pour boiling water on your car keys or something like that, would it kill him?
Norman Swan: Well, it would definitely kill your car keys. As we just said, you only need detergent. There is no doubt that cooking and high temperatures kill this virus, but that doesn’t mean you want to sprinkle it all in boiling water. It’s dangerous, you can scald yourself, you can scald the kids around, and you don’t have to. And it’s not going to convincingly catch the whole virus. Because, come to think of it, let’s imagine you pour boiling water on the package or something like that. By the time you impact the piece of cardboard or whatever, yes, there may not be a lot of coronavirus left, but there may be a coronavirus down there that you haven’t actually treated. So you’d better manage that with what we know, which is a detergent, if you’re talking about surfaces, if you’re talking about cleaning products or alcohol, spray 70% alcohol on it, what will be much more efficient and you can always start the car in the morning.
Tegan Taylor: Okay, so now for my cold question. Andrew asked us to buy milk that goes in the fridge or things that go in the freezer, frozen meats wrapped in plastic. Do we know how well the virus survives at low temperatures?
Norman Swan: I think we can safely say that the virus will survive in the refrigerator and that it will probably also survive in the freezer. This is not absolutely convincing evidence on this, but the safe assumption to be made is that it could survive in both the refrigerator and the freezer. So that means if you want to be really safe and you have a carton of milk, you just need to take detergent and wipe the carton of milk before putting it in the fridge, same with a bottle of milk, etc. And then it is unlikely that there is a virus on it. You probably just want … I think general hygiene, you probably just want to clean the fridge frequently with detergent, so you don’t leave things lying around. And frozen meats, again, if they are in a package, if you wipe the package with detergent before putting it on, then rinse that detergent so that there is no soap in your freezer, then when you take it out, it’s not going to be a virus on it. But if you put it on without washing it and there is a virus, it will probably still be on it. So I think you just need to use common sense and treat each contact as a potentially risky contact and wash your hands before and after.
Tegan Taylor: So we know that washing your hands is a very important part of preventing this virus from entering our faces, that’s how we get sick. Tony asks; Should he coat his hands with antibacterial liquid to wash his hands before going to the stores? Is there a value for this or does it need water to activate the flavor?
Norman Swan: You really have to create a soapy effect to activate the surfactant, which breaks down fat. So simply putting the soap itself will give you a surfactant effect, but in fact diluting it with water and lathering is really what you want to see to kill the virus.
Tegan Taylor: So there is the detergent itself, then the friction that works together.
Norman Swan: Friction and foaming are really important elements.
Tegan Taylor: Well, that’s it for Coronacast today. We are planning a mental health episode for next week, with special guest Ian Hickie, so if you have mental health issues, go to abc.net.au/coronavirus, and just be sure to add the word Coronacast in your question so that we can find it easily.
Norman Swan: And we will see you tomorrow. And tomorrow we will post our episode of social media myths, so subscribe and keep an eye on that. See you later.
Tegan Taylor: See you later.