Several Alabama schools were closed Monday due to a flu outbreak, officials said.

Albertville City schools will resume classes on Tuesday, and Marshall County schools, Boaz City schools and Guntersville City schools are expected to resume classes on Wednesday, WAFF reported.

School officials decided to close schools after 13 percent of students — up from the usual 10 percent — called out sick.

The schools said the closures would allow them to sanitize the classrooms as well as give students time to recuperate so they are not contagious to others.

“Stay at home. Do not go to your friend’s house. Don’t gather in groups because this is where people usually end up catching a virus is when you’re in a group and everybody is coughing on each other, so I would say just stay at home,” Albertville health science teacher Leanne Killion told WAFF.

Cindy Saye Wigley, superintendent of Marshall County schools, apologized to parents for inconveniences as a result of the closures.

“We understand dismissing school creates a hardship on many of our parents; however, the health and safety of our students must continue to be our number one priority. At this time, the epidemic is not only having an impact on our students but also our staff, preventing us from effectively serving our students,” she told AL.com.

Widespread flu outbreaks have been reported in 36 states, according to the CDC.