STACEY VANEK SMITH, HOST:
By December 1, the U.S. death toll from coronavirus could reach 300,000. That is the grim new projection from a prominent team of forecasters at the University of Washington. But the researchers also find that if most Americans start wearing masks, tens of thousands of lives could be saved. We're joined now by NPR's global health correspondent Nurith Aizenman.
NURITH AIZENMAN, BYLINE: Hi, Stacey.
VANEK SMITH: So let's start with that terrible number. Three-hundred thousand Americans could potentially die by December. Could you give us some context there?
AIZENMAN: So as you noted, this comes to us from researchers at the University of Washington, specifically its Institute for Health Metrics and Evaluation. And they are projecting that between now and December 1, about 137,000 more people will die of coronavirus. Add those deaths to the roughly 160,000 who have already died, and you get to that total of nearly 300,000 dead. And that's about five times the number of people who die of flu each year. In fact, if this projection pans out, coronavirus will likely be the third-leading cause of death in the U.S. for 2020, only behind heart disease and cancer.
VANEK SMITH: What's driving this prediction?
AIZENMAN: The quick answer - a bad current situation hitting up against even worse conditions come autumn. Right now, we're already seeing high rates of transmission across many states. The good news is in some of the hardest-hit ones - Arizona, Texas, Florida - people have modified their behavior enough to start bending the curve. Unfortunately, researchers also expect to see the flip side, which is this pattern where as soon as things start to get better off, both officials and regular people tend to ease up too quickly. And then, come November, the country will likely be hit by what the scientists say is a really severe effect from cold weather. Here's the lead researcher Chris Murray.
CHRIS MURRAY: November is a month when we expect the increase of transmission due to seasonality will start to be stronger. We would see approximately a 50% increase in transmission, everything else being the same.
AIZENMAN: And that's the impact for the northernmost states, the colder regions where people will have to spend more time indoors, the virus may thrive in colder air.
VANEK SMITH: Is there anything that could change this scenario?
AIZENMAN: Well, this forecast is already factoring in states moving to stay-at-home orders and shutdowns once cases skyrocket. They're also assuming 50% of schools will be doing online-only instruction. But the model does not assume widespread mask use, and that is what could change things.
VANEK SMITH: Yeah. We have heard, obviously, a lot about masks recently. What kind of difference are we talking about with masks?
AIZENMAN: OK. So right now, the researchers say, nationwide in the U.S., about 50% of people are wearing masks when they're out and about. So the researchers ran a simulation to see what happens if, starting today, that was upped to 95% of people wearing masks. And they find that about half of the deaths between now and December 1 would be prevented.
VANEK SMITH: Is it realistic that that many Americans would start wearing masks?
AIZENMAN: Yeah, that's the key. The researcher said it's an interesting analysis they've done that suggests that when officials mandate masks, use goes up by 8 percentage points. And if those mandates include penalties, it's a 15-point bump.
VANEK SMITH: And quickly - I mean, obviously, this is a forecast from just one team. How does this fit in with other projections?
AIZENMAN: Well, I spoke with Nicholas Reich at University of Massachusetts Amherst who set up a system for harmonizing many different forecasts. He says that long-term projections like this one can be really useful in terms of helping us determine, you know, if you take this precautionary step, how much does it help? But Reich also says that when it comes to hard numbers for predicted deaths, even four weeks out, these forecasts do vary pretty widely.
VANEK SMITH: Nurith Aizenman, thank you.
AIZENMAN: You're welcome. Transcript provided by NPR, Copyright NPR.