Why did CDC change isolation guidelines? Officials explain as some question its safety
The Centers for Disease Control and Prevention recently changed its COVID-19 isolation guidelines as the omicron variant spreads throughout the United States — prompting confusion from some and leaving others questioning the safety of the new recommendations.
The CDC on Monday, Dec. 27, said people who are infected with the coronavirus now need to isolate for five days instead of 10 if they are asymptomatic or if their symptoms are “resolving.” But the isolation period should be followed by five days of wearing a face mask around others. A negative COVID-19 test is not required to end isolation.
The updated guidelines followed a push from some experts to shorten the isolation period as omicron, which seems to transmit and evade vaccine more easily, spreads. More people will likely become infected — leading some experts to say the 10-day isolation period wasn’t sustainable as it could strain the workforce in critical industries.
But now, some experts are questioning whether a five-day isolation, without a testing requirement, is safe.
Why the CDC changed its isolation guidelines
The agency said its decision to shorten the isolation period was “motivated by science” that shows the majority of coronavirus transmission usually occurs early in an infection: one to two days before symptoms start and two to three days after.
“If you map that out, those five days account for somewhere between 85% to 90% of all transmission that occurs,” CDC Director Dr. Rochelle Walensky said on CNN’s “New Day.” “So we really wanted to make sure that during those first five days you were spent in isolation.”
Walensky went on to say that the CDC also took into consideration what length of time people would “tolerate.”
“Some science has demonstrated less than a third of people are isolating when they need to,” Walensky said. “And so we really want to make sure that we had guidance in this moment — when we were going to have a lot of disease — that could be adhered to, that people were willing to adhere to and that spoke specifically to when people were maximally infectious.”
The CDC’s lack of a testing requirement to end isolation has also been a point a criticism.
But Dr. Anthony Fauci, the nation’s top infectious disease expert, said on MSNBC that the antigen tests that are used are good at determining whether or not a person is infected but that they don’t have a “good predictive value as to whether or not you’re transmitting” the virus.
He also said that the risk of transmitting the virus in the second five days following infection is low.
“The original (Food and Drug Administration) approval of the test was not for the purpose of determining, if multiple days following infection, that you are able to transmit,” Fauci said on MSNBC. “And for that reason the CDC said it was not necessary to have a test because the risk is low.”
Fauci said a concern for the disruption to society also factored into the decision to change the guidelines.
“They were trying to strike a balance: how do we do good public health principles at the time we don’t have to get to the point where you’re forced to essentially shut the country down,” he said.
Criticism of the change
In addition to some experts pushing for a shorter isolation period, the CDC also faced pressure from some companies to shorten it, The New York Times reported.
Delta Airlines CEO Ed Bastian sent Walensky a letter on Dec. 21 asking that the CDC reconsider the 10-day isolation period for fully vaccinated people, saying the requirement would “significantly impact” its operations.
JetBlue and Airlines for American, which represents several airlines, made a similar plea, according to the Times. But the Association of Flight Attendants said in a letter to Walensky on Dec. 23 that it wanted the guidance to be based on “science, not staffing,” and that the decision should be “made by public health professionals, not airlines.”
Now, some experts have cast doubt on the safety of the CDC’s new guidelines, saying the science the CDC used to make the decision came before omicron and that emerging evidence shows vaccination status plays a large role in transmissibility of the virus, McClatchy News previously reported.
In Michigan, the state Department of Health and Human Services said it will keep following its current isolation and quarantine guidelines and that it “intends to review the supporting evidence behind this guidance, while awaiting additional information from the CDC.”
Dr. Walid Gellad, a professor of medicine at the University of Pittsburgh, took issue specifically with the fact that the new guidance applies to people who still have symptoms.
“Just like in the summer with CDC mask guidance, this seems created to allow some amount of COVID transmission to happen,” Gellad tweeted. “Fine. “My personal advice is not to take this as your own personal guidance on what might be safe for you or people close to you, like grandma.”
Other experts criticized the lack of a testing requirement.
“On the one hand: I’m all for following the science for the vaccinated & asymptomatic. No reason to keep people home unnecessarily,” Dr. Megan Ranney, the academic dean for the Brown University School of Public Health, tweeted. “On the other hand: the data shows a RANGE of infectiousness. Requiring a rapid test before ending isolation (esp for folks like, say, healthcare workers) would be far, far, far safer.”
But some experts, including Ranney, acknowledged that shortening the isolation period would relieve stress on hospitals and businesses as more workers become infected with omicron.
This story was originally published December 30, 2021 at 11:52 AM with the headline "Why did CDC change isolation guidelines? Officials explain as some question its safety."
