In another guide, the CDC tells people who have recovered from Covid-19 that they can leave their homes after five days - and while traveling for the next five days, they should avoid being around more than 80% of the American public.
Dr. William Schaffner, adviser to the CDC for four decades, said it was "unlikely, unreasonable and unrealistic" to think that Americans would follow one of the agency's proposals.
"Making recommendations for public health - they are not a platonic ideal," Schaffner added. "They have to work in the real world."
Such out-of-touch counseling has been a hallmark of many CDC recommendations long before the pandemic began, and the agency needs to do better, said current and former health officials and physicians who have worked with the CDC on health counseling.
"As we say in Tennessee, that dog will not hunt," said Schaffner, an infectious disease expert at Vanderbilt University Medical Center.
Over the past few weeks, the agency has been criticized for issuing guidelines that were confusing or counter-intuitive. In this case, the critique is different; The concern is that CDC employees, even though they are hard-working, smart, and well-meaning, do not always consider whether Americans will - or even can - follow their advice.
CNN asked CDC director Dr. Rochelle Walensky on the two guides. In a statement, Walensky said the agency "prioritizes academics over athletics because of the increased risks involved in some leisure activities. When followed, our school guidance has been incredibly effective. By the fall, 99 percent of schools were able to to remain open during the intense delta wave of COVID. "
Part of the problem, Schaffner and others say, is that CDC researchers are sometimes stuck in a bubble.
"You have nerds - literally science nerds - who write these things," said Dr. Otis Brawley, who worked with the CDC on cancer counseling while serving as chief physician at the American Cancer Society from 2007 to 2018.
"I really feel with the people at the CDC," he said. "They are cursed if they do, and they are cursed if they do not."
CDC School Guide
The CDC cites football and wrestling as examples of high-risk sports and says that "high-risk activities outside of school are those where increased exhalation occurs, such as activities involving singing, shouting, banding or exercise, especially when performed indoors."
Paul Imhoff, president of The School Superintendents Association, told CNN that while schools have made great efforts to curb the spread of Covid-19, he does not know of any schools that have canceled activities such as football or band or choir. Such activities, he said, are "important to students' mental health."
"When schools make decisions about having choirs and bands and wrestling, it's about making sure our kids are healthy in every way. I think everyone does their best to take care of the whole kid," Imhoff says. , a school superintendent in Ohio.
In his statement to CNN, Walensky said that the CDC "developed our school guidance, knowing that school administrators, teachers and parents looked to us at the CDC to get their children back into the enriching environment of the classroom, and it was a priority to get our children back. safe in school, "adding that" vaccines are available for school-age children, adding another layer of protection and improving school guidance. "
Schaffner, however, questioned why the CDC would advise schools to cancel extracurricular activities involving shouting when children shout regularly.
"I could take you by the hand and say, 'let's go through three colleges.' for vaccination practices.
CDC Insulation Guide
The Computational Epidemiology Lab at Boston Children's Hospital estimates that more than 80% of Americans have at least one of the conditions on the CDC's list, according to an analysis the group did for CNN.
Schaffner questioned the practicality of avoiding 80% of the people around you.
"How do you know if people have heart disease or diabetes? How are you going to find out? Can you recognize anyone who is pregnant or has a sickle cell or is a former smoker?" he said, mentioning some of the issues on the CDC's list of who to avoid.
When asked for advice at the briefing, Walensky said the agency asked people to "avoid your family members or others who may be immunocompromised, avoid visiting grandma or a nursing home."
'Round, red tomatoes'
When considering the CDC's school and isolation guide, Glen Nowak thinks back to a foodborne illness that occurred in 2008 while he was the CDC's head of media relations.
It was unclear exactly what had made people sick, but one of the possible culprits was tomatoes, so Nowak says the agency's scientists wanted to tell the Americans that they should stop eating tomatoes.
Nowak says he told the researchers that this was quite broad, given that tomatoes are a very common food. He says he asked his colleagues to be more specific - was there a particular type or source of tomatoes that Americans should avoid?
Nowak said that while working at the CDC from 1999 to 2012, researchers repeatedly developed guidance without thinking through the next step: Is it possible to follow the advice we have written? If so, what exactly should someone do?
"It was a constant challenge. It came up in many circumstances," said Nowak, co-director of the Center for Health & Risk Communication at the University of Georgia.
"Scientists and experts have a really hard time seeing the world through the lens of ordinary people," he added.
Changes the lens
One way to move that lens is to seek input from external groups, but it has been more difficult during the pandemic, where the agency has had to move faster. Spokesmen for the Superintendent Association and the National Association of Secondary School Principals said the CDC did not reach out to them for a conference on guidance on school sports and recreational activities.
A federal health official familiar with how the CDC is developing its guidelines said the agency should also make better use of its own communications specialists.
"There is simply no place at the table for communicators when it comes to actually developing guidance," the official said, adding that CDC communications specialists would "consider whether the guidance being developed is really practical."
The official asked to speak anonymously because they were not authorized to speak on this issue.
Brawley noted that the pandemic has posed unusual challenges in issuing guidance.
He said under normal circumstances that experts would first gather all relevant studies on a particular topic and then discuss - sometimes for months - what the best advice to the public would be, and also consult outsiders to get their input.
"When I was in the American Cancer Society, when we sat down to write guidelines for lung cancer, it took a group of 14 people almost a year to come up with the wording. And then we tested the wording on focus groups, in collaboration with doctors. And nurses and lay people to try to find out if we communicated effectively, "he said. "The CDC does not have time to do that."
Brawley, now a professor at Johns Hopkins University, said there is an alternative to the way the CDC issued their guidance. For example, if schools are not ready to cancel football or choirs, then the CDC could just explain that these are high-risk activities, without directly discouraging them.
He said it would be important to explain the research showing that these are high-risk activities, something the CDC is not doing on their site right now.
"I would put the surveys in because I have a feeling that a large portion of the American lay population does not appreciate how we come up with these rules. It's not just a few people in Atlanta who come up with these in their offices at the CDC. The rules are based on real observations in real populations, "he said.
But he added that the CDC would still likely come under fire for its guidance, at least from some people.
"There is no way the CDC can win," he said.
CNN's Danielle Herman and Jamie Gumbrecht contributed to this report..