In just 24 hours, four teachers in Broward County, Fla., died from COVID-19.

At least three of the teachers were unvaccinated, CBS News reported.

"Within a 24-hour span, we had an assistant teacher pass away, a teacher at her school pass away, an elementary teacher pass away and another teacher at a high school," Broward Teachers Union president Anna Fusco told CBS News.

The deaths were announced a few days after Broward County's school board pushed back against Governor Ron DeSantis' ban on mask mandates in schools that was signed into effect on July 30.

The board voted 8-to-1 to require students to wear masks in school, saying it would help keep students and teachers safe. Those with legitimate concerns or health issues can opt out, CBS News reported.

Fusco said news of the teachers' deaths was "extremely frightening," but too common. "I hear this every day. Whether in Broward or elsewhere," she said.

As schools around the country prepare for students to fill the halls again, Fusco said she's grateful for the Broward County School Board's decision.

"We got a little bit of relief, keeping mask protocols, hand sanitizer, extra sanitizing," she said.

With the Delta variant surging throughout the country, Florida has been breaking records for new COVID-19 cases and hospitalizations, CBS News reported.

K-12 students and staff returning for in-classroom learning should wear masks, the American Academy of Pediatrics and the U.S. Centers for Disease Control and Prevention recommend.