CDC director Dr. Rochelle Walensky explains why agency changed COVID-19 guidelines

Confusion and criticism have followed the revamped COVID-19 guidelines issued by the Centers for Disease Control and Prevention, so the agency’s director, Dr. Rochelle Walensky, has been trying to clear up the confusion and give more background on why the rules have changed.

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Walensky appeared on “CBS Mornings” to say that the change isn’t because tests are in short supply.

“This really had nothing to do with supply. It had everything to do with knowing what we would do with the information when we got it,” Walensky said, according to CBS News.

People who have tested positive for COVID-19 but show no symptoms can now leave isolation after five days without being retested. But the CDC said they should still be masked for five days after.

The change is due to how the CDC believes COVID-19 is transmitted.

“What we do know is about 85% to 90% of viral transmission happens in those first five days, which is why we really want people to stay home during that period of time,” Walensky told “CBS Mornings.” “And then mask for the rest of the time to capture that last 10% to 15%.”

Walensky added that a negative test is not required because it can show remnants of the coronavirus up to 12 weeks, even after a person is not contagious.

Doctors also don’t know if antigen tests can determine if a person can be contagious at the end of the infection.

Walensky stands by antigen test usage five days after someone has been exposed to COVID-19 or if they get any symptoms.

But not all agree on the move.

Dr. Celine Gounder, an NYU and Bellevue Hospital infectious disease specialist, has harsh words for the Food and Drug Administration when it comes to antigen tests.

“Frankly, the FDA has had two years to do these assessments that Dr. Walensky is referring to: whether they’re as good to make that initial diagnosis to say you’re contagious as they are for saying you are no longer contagious,” Gounder said on “CBS Mornings.” “They’ve had two years and have been dragging their feet for two years.”

She also says that the lack of available tests is what is actually behind the change to require testing to stop the quarantine or isolation periods.

Walensky also said the change was made due to what the CDC believes “people would be able to tolerate,” she told CNN.

Walensky said on CNN that the CDC found that less than a third of people have been isolating when they need to and that the agency looked at people’s behaviors, along with the science of how COVID-19 spreads, in arriving at the five-day window.

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