ARI SHAPIRO, HOST:
NPR health correspondent Allison Aubrey has been listening in on that conversation and is with us now.
Allison, what stood out to you most from what we just heard Dr. Walensky say?
ALLISON AUBREY, BYLINE: Hi, Ari. I think what stands out most is her explanation on why a shorter isolation period after testing positive down to just five days makes sense. There were some new evidence of a shorter incubation period with Omicron just three days ago, at three days or so. And as she said, prior studies show most people with coronavirus are most infectious in the first few days after an infection, of the infection. But there's a bit of guesswork here, Ari. Vaccinated people are less likely to be infectious, and unvaccinated people may not know when exactly they were infected. So a lot of infectious disease experts I talked to you tell me the policy could be stronger.
SHAPIRO: Where do they see weaknesses? What did those experts tell you?
AUBREY: You know, in the days coming out of isolation, say between day five and day 10, more specific masking requirements would be useful. The CDC does recommend masking, but recommendations only work if people follow them, as Dr. Walensky just said. I spoke to Emily Landon - she's an infectious disease doctor at the University of Chicago - about this.
EMILY LANDON: The CDC's right. Their guidance, as written, follows the science. Five days is when the majority of transmissions happened, but that masking piece of the second half is absolutely essential. And my issue with that is that the last time they made a recommendation that relied on people to use the honor system to wear masks, people didn't wear masks. So I think we should have learned a lesson from that.
AUBREY: You know, I think she says the CDC is in some ways kind of stuck between a rock and a hard place. There's pressure to get people back to work, back out again but also sort of an inability to get people to comply with the very things that can help protect against the spread, including masking and the use of rapid tests, which are hard to come by right now.
SHAPIRO: NPR health correspondent Allison Aubrey, thank you.
AUBREY: Thank you.
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