The largest teachers union in the United States influenced federal health officials to include rules for universal masking in school buildings, according to newly published emails obtained by a government watchdog group.

The number of school closures due to COVID-19 is increasing alongside pediatric infections as the country's public school system fully reopens – in many places with low vaccination rates and mask-optional policies.

More than 1,400 schools across 278 districts in 35 states that began the academic year in person have closed, according to Burbio, an organization that's tracking how schools respond to the ongoing pandemic. The figures are up from 698 schools across 158 districts in 25 states.

Just as doctors feared, more children are getting hit hard by Covid-19 as the Delta variant tramples across the country.

And the school year just started.

"What we're seeing now is extremely concerning," said Dr. Edith Bracho-Sanchez, associate professor of pediatrics at Columbia University Irving Medical Center.

"This virus is really going for the people who are not vaccinated. And among those people are children who don't qualify for the vaccine and children and teens who qualify but are choosing not to get it."

Among the latest sobering statistics:

After more than a year of distance learning, many school-age children in the U.S. have gone back to the classroom. And while the highly transmissible delta variant of the coronavirus certainly triggers mixed feelings about kids’ returning to school, parents have maintained for the most part that they prefer in-person learning, at least some of the time, to the entirely remote, virtual learning that took place largely online during the past school year.

Florida’s ban on school districts imposing mask mandates is now no longer legally enforceable as a ruling striking down the state policy took effect Thursday—but the Florida Department of Education still intends to move forward with its plans to withhold funding from schools that have mask mandates by immediately appealing the ruling.

There’s just over a week left before the National Football League’s new season begins, and its already bickering with the players’ union over Covid guidelines.

The NFL Players Association agreed to renew Covid policies for the 2021 season, mainly emulating policies from 2020, including daily testing and mask mandates. However, with the delta variant causing a surge in Covid cases, there are ongoing discussions about mandating vaccines for players.

A Florida judge has struck down a state order that bans school districts from mandate mask-wearing.

Circuit Judge John C. Cooper sided with parents who said that the state’s Constitution requires that schools keep students safe. They argued that mask mandates would keep students safe amid the pandemic.

Wading into the bitter debate about face mask mandates in schools, President Joe Biden is threatening civil rights lawsuits against states that ban such requirements. "Some politicians are trying to turn public safety measures…into political disputes for their own political gain," Biden complained last week, saying his administration won't "sit by as governors try to block and intimidate educators protecting our children."

In Melbourne, mounted officers used pepper spray when elements of a 4,000-strong rally broke through police lines.

Police arrested 218 people, and at least seven officers were injured.

In Sydney, where lockdown measures have been extended for another month, more than 1,000 officers dispersed protests.

It came as the state of New South Wales (NSW), of which Sydney is the capital, recorded 825 new locally-acquired cases, the highest number for any Australian territory in a 24-hour period.