(CNN) The polarization surrounding mask mandates is deepening as some state and local officials spar on how to approach face coverings protocols in schools, a debate unfolding as more children contract Covid-19.
In Florida, which has the second-highest rate of new cases per capita after Louisiana, children's hospitals and staff are "overwhelmed," said Dr. Aileen Marty, an infectious disease expert at Florida International University.
"The numbers of cases in our hospitals in children and our children's hospitals are completely overwhelmed," Marty told CNN's Jim Sciutto on Friday evening.
"Our pediatricians, the nursing, the staff are exhausted, and the children are suffering. And it is absolutely devastating ... our children are very much affected. We've never seen numbers like this before," she said.
A surge in Covid-19 cases and hospitalizations, fueled by the rapid spread of the Delta coronavirus variant, is happening in the US as millions of children are returning to schools. It is reigniting conversations on measures to lower transmission so students can safely be in the classroom.
But officials on the state and local levels have not streamlined their back-to-school mask wearing strategy, prompting local districts to create their own rules.
In Texas, the Houston Independent School District's superintendent said he would move to mandate masks upon students' return on August 23, despite GOP Gov. Greg Abbott's executive order prohibiting school districts and other local officials from requiring mask wearing.
"We have not seen kids pile into pediatric ICUs across the South like we're seeing right now," Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine, told CNN on Friday.
And as Covid-19 cases climb in Florida, Republican Gov. Ron DeSantis issued an executive order last week, telling the state's health and education departments to create rules preventing local school mask mandates. Two different lawsuits have since been filed against DeSantis over the executive order.
On Friday, Florida's Orange County Public Schools said it would require students to wear masks -- except pupils whose parents opt them out with a signed note. Employees, visitors, volunteers and parents also will be required to wear masks, the district said.
Hillsborough County Public Schools will "require face coverings" for the start of the school year but parents will be able to opt their children out of the requirement, according to a Saturday statement from Superintendent Addison Davis.
"While the outcome may be the same whether we make face coverings optional or required with an opt-out, we believe this decision continues to illustrate that Hillsborough County Public Schools takes public safety seriously," Davis said.
Masks are optional for employees, Davis said.
Returning to schools safely is possible if mitigation efforts, including wearing masks, are implemented, said Dr. Rochelle Walensky, who heads the US Centers for Disease Control and Prevention.
"The places where you see kids in the hospital, the places where you see footage of kids in the hospital, are all places that are not taking mitigation strategies to keep our children safe," Walensky said Friday.
The CDC recommends that everyone -- students, teachers, staff and visitors -- wear masks in schools.
And while the CDC says 50% of the total population is fully vaccinated, children under 12 are still not cleared to be inoculated.
With the highly contagious Delta variant having increased its grip in the US, the daily coronavirus case rate is at its highest level in months.
The US averaged more than 107,140 new daily cases over a week as of Friday -- the first time that average was higher than 100,000 since February, according to Johns Hopkins University data.
The figure has generally risen since the country hit a 2021 low average of 11,299 daily on June 22, according to Johns Hopkins.
Hospitalizations and deaths have been rising, too.
More than 63,250 Covid-19 patients were in US hospitals on Friday -- a number that has generally risen since a 2021 low of 16,152 on June 29, according to the Department of Health and Human Services.
About 497 Covid-19 deaths per day have been in the US in the past week -- well below the country's pandemic peak of more than 3,400 daily in mid-January, but still a 40% increase over the average a week ago, according to Johns Hopkins.
People with compromised immune systems could soon hear about a plan to give them a booster shot.
A decision from the US Food and Drug Administration could come before early September, a Biden administration official told CNN.
The Washington Post reported Friday that in the next week or two, FDA officials are expected to review data on additional vaccine doses for immunocompromised people from the CDC. If the data checks out, the FDA will amend the emergency use authorizations of at least two Covid-19 vaccines to allow the additional doses, The New York Times reported.
The move could affect millions of people who may not have had an adequate response to the vaccine.
That includes people taking drugs that suppress immune systems; some organ transplant patients; and those with certain medical conditions. Research published in JAMA Network Open estimates that 6 million people in the US are taking immunosuppressants that could interfere with the vaccine -- a number the researchers say is likely an underestimate.
As cases rise, hospitals and staff are facing dire situations.
In Louisiana, more than 2,300 people were in hospitals with Covid-19 on Friday -- the highest number since the US Department of Health of Human Services began collecting the data in July 2020.
"And I can tell you the indications are, we will go up by more than 100 more for tomorrow's report," Gov. John Bel Edwards said Friday.
More than more than 6,000 children have tested positive over the last week, Edwards said.
"So in light of that, and the CDC recommendations, the recommendations of the American Academy of Pediatrics, the information that we've received here from the Office of Public Health and leading Louisiana pediatricians, and quite frankly, as a parent myself, I have to ask -- why wouldn't we send our kids to school with a mask on?" Edwards said.
Edwards earlier this week issued an order generally requiring everyone 5 and older in Louisiana -- both vaccinated and unvaccinated -- to wear masks indoors, including in schools but excepting private residences.
Edwards said he has hope, because 300% more people are receiving their first shot in the last month.
And in Tennessee, Republican Gov. Bill Lee issued an executive order that allows hospitals to hire out-of-state health care providers, and to permit retired medical professionals easily back to work. His order also increased bed capacity for Covid-19 patients.
Correction: An earlier version of this story incorrectly described the capacity at Nicklaus Children's Hospital in Miami. The hospital, a 309-bed pediatric specialty hospital, had a total of 214 admissions on Saturday. Of those, 18 were Covid-19 positive and five were in intensive care units.