FORT LAUDERDALE, Fla. (AP) — Millions of students in Florida, Texas and Arizona are now required to wear masks in class as school boards in mostly Democratic areas have defied their Republican governors and made face coverings mandatory.

The three states are all hot spots in the nation's recent COVID-19 surge, and defiant boards in Miami, Dallas, Houston, Phoenix and other urban areas argue that requiring masks protects students, teachers and staff from contracting and spreading the virus as many pediatric hospitals fill.

The districts often cite the Centers for Disease Control and Prevention, which recommends teachers, staff and students all wear masks regardless of whether they've been vaccinated.

"This thing (the virus) is not playing with us," Marcia Andrews, a member of the Palm Beach County, Florida, school board, said this week as it passed a mask mandate, according to the Palm Beach Post. "I don't want to see a kid die."

The governors argue that wearing masks stifles learning and does little to stop the virus's spread but children rarely get seriously ill from the disease. They say mandates violate parents' rights to determine how best to protect their children.

"Texans, not government, should decide their best health practices, which is why masks will not be mandated by public school districts or government entities," Texas Gov. Greg Abbott said when he banned local mask mandates.

Florida Gov. Ron DeSantis, in a July executive order barring masks, cited a Brown University study that examined schools in New York, Florida and Massachusetts. He said it showed masks at schools made little difference, but it had a caveat he doesn't cite: It analyzed cases associated with schools and not cases spread in schools.

One of the study's authors, Brown economist Emily Oster, said recently that she was not consulted by the governor and the study relied on data from before the emergence of the more contagious delta variant. She supports masks in schools.

Dr. Jessica Snowden, a pediatric infectious disease specialist at Arkansas Children's Hospital, said masks are proven to cut the virus's spread among children if worn consistently. She said the delta variant infects children more often and makes them sicker than last year's variants, adding that masks do not impede learning.

"There is lots of evidence that supports masking and there is no evidence that it causes any harm," she said. "Children are much more adaptable than adults are."

Florida and Texas combined make up 15% of the U.S. population but 28% of its recent COVID-19 cases, according to the CDC, and both states have seen their hospitalization numbers skyrocket over the past two months. Arizona's COVID-19 cases have jumped sixfold since June.

Mask rules in U.S. public schools vary widely. Eleven states require masks, including California, Illinois, Louisiana and Kentucky, while Florida, Texas and five other states ban them: Utah, Tennessee, Oklahoma, Iowa and South Carolina. Arizona's ban takes effect Sept. 29. The other states leave the decision to local officials.

In Arizona, Gov. Doug Ducey this week barred districts that mandate masks from accessing a $163 million virus relief pool and said parents could receive $7,000 per student for private schools if their district mandates masks or goes into quarantine. More than two dozen districts, accounting for a third of the state's 930,000 public school students, require masks.

"Safety recommendations are welcomed and encouraged — mandates that place more stress on students and families aren't," Ducey said in a statement.

Save Our Schools, an Arizona group that successfully repealed a statewide voucher program, said Ducey is trying to use COVID-19 to restore public funding of private schools.

"We are ready to fight the abhorrent policies," the group said in a statement.

In Texas, the state's biggest districts, including Dallas, Houston, San Antonio and Austin, are all defying Abbott and requiring masks. Abbott, who recently tested positive for the virus, is fighting the districts in court, but they aren't budging.

"We're going to continue our mask mandate to keep students safe, to keep parents safe, to keep families safe and most importantly our teachers," Dallas school superintendent Michael Hinojosa said.

In Florida, where the battle is particularly heated, DeSantis and the state Board of Education, which he appoints, have threatened to cut funds from districts that impose mandates that don't provide an easy opt out for parents. The state is also allowing students who feel bullied into wearing a mask to apply for a private school voucher.

"Forcing young kids to wear masks all day, these kindergartners, having the government to force them, that's not defying me; that is defying the State of Florida's laws," DeSantis said this week. "This is not something we are making up."

But four of Florida's five largest school districts — Miami-Dade, Broward, Hillsborough and Palm Beach counties — along with mid-size Alachua, the home of the University of Florida, have adopted mask mandates with exemptions only with a doctor's approval. They represent more than a third of the state's 2.8 million public school students.

Miami-Dade, the nation's fourth-largest district with 341,000 students, adopted its mask mandate Wednesday, hours after Superintendent Albert Carvalho told the state board the district would not back down.

"For the consequences associated with doing the right thing, whatever that right thing is, I will wear proudly as a badge of honor," Carvalho said, according to The Miami Herald.

DeSantis has accused the defiant boards of playing politics.

The five Florida districts that have imposed strong mask mandates are all Democratic strongholds that supported President Joe Biden in November's election even as former President Donald Trump carried the state. Biden recently told districts that the federal government would replace any funds the state cuts because of mandates.