The CDC issues a dire warning for the fall if coronavirus measures are not followed

(CNN) A top federal health official is issuing a dire warning: Follow recommended coronavirus measures or risk having the worst fall in US public health history.

"For your country right now and for the war that we're in against Covid, I'm asking you to do four simple things: wear a mask, social distance, wash your hands and be smart about crowds," said Dr. Robert Redfield, director of the US Centers for Disease Control and Prevention.

"I'm not asking some of America to do it," he told WebMD. "We all gotta do it."

Without following the recommendations, this could be "the worst fall, from a public health perspective, we've ever had," he said.

"You can't run away from the numbers," Dr. Anthony Fauci, director of the National Institute of Allergies and Diseases, said during a National Geographic panel Thursday. "You can't run away from the numbers of people who've died, the number of people getting hospitalized, the surges we're seeing."

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Coronavirus continues to spread at high rates across the South, Midwest and West -- even as the total number of new cases has declined following a summer surge.

The country is averaging 53,318 new cases over the last seven days -- down 6% from the week prior. As of Thursday morning, 7 states, Washington DC, the US Virgin Islands and Puerto Rico were trending upwards in new cases of Covid-19.

Adjusting for population, states in the Southeast are seeing the most new cases. Georgia and Florida -- states led by Republican governors who have not issued face mask requirements -- have the highest per capita new cases over the past seven days, followed by Alabama and Mississippi.

Deaths from the virus have remained high.

The seven-day average of daily coronavirus deaths was over 1,000 on Wednesday, the 17th consecutive day the US averaged over 1,000 deaths per day.

"How long we're going to have to be doing this depends totally on us," Fauci said Thursday. "If we keep running away from the reality of the need to do it, it could linger on and linger on."

On coronavirus vaccines, Redfield is cautiously optimistic that one or more vaccines will be ready by the start of 2021. There are 270 active trials for coronavirus treatments, experts say.

But anti-vaxxers have taken to social media to spread lies about the future coronavirus vaccine. Some include claims it contains monkey brains or that it's a CIA plot to take over the world. Others allege the vaccine will include an invisible trackable tattoo or it will disfigure those who take it.

As the lies spread, the government's multi-billion-dollar vaccine effort has yet to come up with a public education campaign to counteract the propaganda.

"We are behind here," said Dr. Francis Collins, director of the National Institutes of Health. "We haven't done a good job of getting (coronavirus vaccine) information out there."

The stakes are high. A third of Americans said they'd not get vaccinated against coronavirus, even if the vaccine is widely available and low cost, according to a CNN poll in May.

"Speaking for myself, I think I underestimated the level of public resistance," Collins said. "I didn't expect it to be that widespread."

Dr. Tina Hartert of the Vanderbilt University Medical Center said lack of faith in the vaccine can lead to major outbreaks. She described the government's communication on the vaccine as crucial.

"We should have started on this months ago but it's never too late to start this important messaging. Because otherwise the messaging people will listen to is the story of one child from another parent," Hartert told CNN's Anderson Cooper.

Over 2,000 people quarantined as schools reopen

Nationally, over the past seven days, the United States is averaging about 53,000 new cases per day, down 11% from the week prior. As educators and parents clash over starting in-person classes, some schools that have reopened have seen new cases.

More than 2,000 students, teachers and staff have been placed under quarantine in the few reopened districts in several states, a CNN tally of reported cases shows. Of those, at least 230 positive coronavirus cases have been reported among the school districts reopened for in-person learning.

Supporters of the Cherokee County School District's decision to reopen schools cheer on faculty arriving to the district's headquarters in Canton, Georgia.

In Georgia, more than 1,100 students, teachers and staff in the Cherokee County School District. about 40 miles north of Atlanta, are under quarantine due to dozens of Covid-19 positive cases or exposure. Schools reopened 10 days ago.

In Florida, a day after the Martin County School District reopened for in-person teaching, an entire elementary class and one bus route were placed under quarantine after a student showed coronavirus symptoms, spokeswoman Jennifer DeShazo said Wednesday.

Several other states including Mississippi, Alabama, Oklahoma and Indiana reported cases of teachers, students and athletes testing positive for coronavirus. At Oklahoma's Broken Arrow Public Schools District, 33 employees tested positive last week, Superintendent Janet Vinson said.

The White House has released new recommendations for schools. They are primarily basic hygiene tips and don't outline what schools should do if they find coronavirus cases in their halls. The recommendations also encourage the use of masks, but do not require students, teachers or staff to wear them.

In new guidance released Thursday, the American Academy of Pediatrics (AAP) advised that face coverings can be worn safely by children over the age of 2, except for rare exceptions.

"Just like children understand that they must wear bicycle helmets and buckle into their car seats, they will come to learn to wear masks routinely when necessary," AAP President Dr. Sally Goza said in a news release . She added, "As parents prepare to send their children to school and into childcare settings, cloth face coverings should be part of their new normal."

Experts weigh the return of college sports

The debate continues to rage over collegiate sports and whether student-athletes can safely compete during a pandemic.

"We're moving into very troubled waters right now," Dr. Brian Hainline, chief medical officer of the National Collegiate Athletic Association (NCAA), warned in a webinar Thursday with the Infectious Diseases Society of America.

When officials began discussing a return to sports in the spring, Hainline said, they anticipated a "continue downward trajectory" of cases and deaths and a national surveillance system, with testing and contact tracing.

"And that hasn't happened," he said.

Dr. Colleen Kraft, an associate professor of medicine in the Division of Infectious Diseases at Emory University's School of Medicine, said collegiate sports are prevented from safely returning because the wider community has yet to uniformly use masks and social distance, among other mitigation efforts.

"I want to take a moment and remind everyone that we have within our ability to protect ourselves at all times from this virus," Kraft said during Thursday's webinar.

Hainline said pushing some sports back to the spring could work, but much depends on how the US as a whole controls the virus.

"It's going to be where are we as a country and where are we as humanity, and making decisions for one another so that we get through this pandemic together," he said. "It's not just about football in the spring. It's more importantly, where are we as human beings taking care of one another."