CDC Expands Definition Of Being At Increased Risk Of Having Caught The Coronavirus

ARI SHAPIRO, HOST:

The Centers for Disease Control and Prevention is expanding its definition of what it means to be a close contact of someone infected with the coronavirus. NPR health correspondent Rob Stein has the details and joins us now.

Hi, Rob.

ROB STEIN, BYLINE: Hey, Ari.

SHAPIRO: There's a bit of a delay on your line, but tell us about what this changes that the CDC is making.

STEIN: Sure. The CDC is changing the definition of what should be considered a close contact of someone who's infected with the virus. You know, for months now, the CDC said anyone who had spent at least 15 minutes within six feet of someone who was infected should be considered a close contact. That means that, you know, they're at risk for having caught the virus.

The CDC is now changing that definition to say that those 15 minutes - they don't have to happen all at once. They can happen in little bits over the course of a 24-hour period - you know, brief encounters of a few minutes here or a few minutes there like, you know, a three-, five-minute chat. But if they add up to 15 minutes over the course of 24 hours, that person becomes a close contact.

SHAPIRO: What are the implications of that change?

STEIN: So, you know, the CDC recommends that anyone who is a close contact should quarantine for 14 days and get tested for the virus, you know, to try to prevent the virus from spreading and prevent new outbreaks from occurring. So this could expand the number of people who would be considered to be close contacts. So a lot more people could be told they should quarantine.

And you can imagine, you know, the impact this could have on workplaces and schools, you know? People who may not work in, say, the same office as the person who got infected could end up being considered a close contact because, you know, they spent a few minutes here or a few minutes there in the hallway, at lunch, in the elevator with an infected person. And that all added up to 15 minutes over the course of a day.

SHAPIRO: Did the CDC explain why it decided to make this change?

STEIN: Yeah. So it's really interesting. The decision was triggered by the case of someone who appears to have caught the virus that way. It was a 20-year-old guard at a prison in Vermont. At first, no one could figure out how this guard got infected. He wore a cloth mask, gown, eye protection whenever he was around infected inmates. The inmates wore masks most of the time.

And here's the puzzling thing. The guard hadn't been within six feet of any of the infected inmates for 15 minutes or more at any one time. So state and federal health officials lost this - launched this intensive investigation that included scouring the surveillance video inside the prison. And when they pieced it all together, it turns out that the guard had 22 brief encounters with the infected inmates of, like, only a minute at a time, but they added up to 17 minutes over the course of an eight-hour shift. The guard had no other close contact with anyone infected outside of work and hadn't traveled. So, you know, the investigators conclude that's how he got infected.

SHAPIRO: So many decisions that the CDC has made during this pandemic have been second-guessed by other health professionals. So what do the public health experts you're talking to today make of this new revision?

STEIN: So, you know, most of the public health experts I've been in touch with say it probably makes sense. But, you know, some do worry what this means on a practical basis. You know, health officials already can't keep up with the number of people they're supposed to be tracking down to notify that they're at risk, you know, to try to get them to quarantine, though nowhere near enough health workers to keep up. And so, you know, not enough is being done to try to help people to make sure they quarantine safely.

So there's a lot of concern that, you know - what kind of headaches this could cause for, like, employers and schools who've been trying to do things like move people around so they don't spend more than 15 minutes at a time with other people. So, you know, you can see how this might ripple through the economy and schools and any plans to try to, you know, reopen safely.

SHAPIRO: Yeah. That's NPR health correspondent Rob Stein.

Thank you, Rob, for the update.

STEIN: You bet, Ari.

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