As we approach the one-year anniversary of COVID-19 in the commonwealth, VPM News is providing an update on the science of staying safe from the virus that's killed over 500,000 Americans. Host Benjamin Dolle recently spoke with Virginia Tech professor Linsey Marr about her research. A transcript of that conversation follows.
Benjamin Dolle: You're listening to VPM News. I'm Benjamin Dolle. Over the course of the pandemic, our understanding of COVID-19 has evolved as researchers have studied it more and learned how it transmits. Dr. Linsey Marr, the Charles P. Lunsford, Professor of Civil and Environmental Engineering at Virginia Tech has been studying the virus. Dr. Marr, thank you for joining me today.
Linsey Marr: Thanks so much for having me.
Dolle: Early on in the pandemic, some experts started talking about a risk budget or how much risk people can take based on their susceptibility. How would you describe that?
Marr: I would think of it as you can have a certain amount of exposure to the virus, and once you've used that up, then you should not continue to do further activities. So maybe you can choose, okay, I'm going to the grocery store, but I'm not going to get together with my friend outside. Or maybe you can do both if you have a higher risk budget.
Dolle: As an example, what would a daily risk budget look like for somebody who had been vaccinated versus somebody who had not yet gotten vaccinated?
Marr: Well, in the first case, you know, you're young, you're healthy, you're vaccinated, that's the, that person is very unlikely to have a severe case of COVID where they have to be hospitalized and experienced severe symptoms. So that person's budget would be higher than compared to the other person who's unvaccinated, older, and so we're talking about different activities. Now, at the same time, we don't know for sure whether that vaccinated person can still spread the virus. It's probably less likely, but that person still needs to be careful that even though they themselves are not getting sick that they're not spreading it to other people.
Dolle: Right now, what types of activities do scientists consider high risk and which ones are considered a lower risk?
Marr: High risk involves any type of activity where you're gathering indoors with a lot of people and without masks. Things like going to a restaurant and eating indoors or having a gathering at your house. Those would be high risk activities. There's certain workplaces also that are high risk places like meatpacking plants and prisons we know where there's people working together closely indoors.
Dolle: And what are some things people should take into consideration, either on their own or with their family and friends, when determining whether or not an activity is worth taking that risk?
Marr: Well, we know for certain that there’s several things that we can do to reduce the risk, and that includes wearing a mask, especially if it's a good mask, avoiding crowds. If you are indoors with other people, crack a window or door to keep the air moving through there and prevent any virus from building up.
Dolle: You and many other scientists at the CDC have begun suggesting that people wear two masks when they go out. What makes double masking better and how does double masking compared to something like, say, an N95?
Marr: Well, if you have access to an N95, that's going to give you the best protection. If you don't, then other strategies such as double masking, where you wear a surgical-type mask first and then you put a tight-fitting cloth mask on top of that, can get you up near to N95-type of protection. But the main thing is that you want a mask that fits well, without gaps around the nose or the cheeks, that has some kind of fabric or filter material that can block small aerosols that contain the virus and something that's easily breathable. So there reaches a point of diminishing returns where if you have too many layers in your mask and it's hard to breathe through, one you won't want to wear it and secondly, it'd be easier for air to leak in around the sides. If you're going into a higher risk situation, indoors with lots of people, you're going grocery shopping or if you're on public transit, that would be the time to double mask are wear your best mask. Now if you're outdoors with other people or you're in an uncrowded indoor environment, then you can think about wearing something that maybe is more comfortable that you can wear for longer periods of time.
Dolle: All right. Well, thank you for speaking with me today.
Marr: Thanks so much for having me.
Dolle: Once again, we were speaking with Dr. Linsey Marr from Virginia Tech. You're listening to VPM News.
