A Twin Cities metro area school shifted to e-learning after a flu outbreak impacted nearly a quarter of its students.

A message posted on the Math and Science Academy Facebook page on Tuesday confirmed that more than 20% of students were out with the flu. Classes were canceled for the rest of the week at the Woodbury charter school. Students will instead learn virtually.

According to the school's executive director, Kim Hinton, 145 students were absent on Tuesday. The academy, which enrolls students in grades 6 through 12, has about 800 students total.

"With the holidays coming and all of that, we just really did not want to have a complete meltdown of everybody being sick," Hinton said.

Melissa McMahon, senior epidemiologist with the Minnesota Department of Health, said flu season is "definitely picking up" in recent weeks.

"We're seeing an increase in hospitalizations … school outbreaks, long-term care outbreaks and outpatient visits," she said.

The state health department says, so far this year, there have been 113 hospitalizations. That's more than double what hospitalizations were this time last year.

"As we kind of go into the winter holidays, we'll probably see more increases until about mid-January," McMahon said.

McMahon says parents should be on the lookout for fevers, coughing or a persistent runny nose. She says children with those symptoms should stay home, and reminded that it's still not too late to get your flu shot.

In the meantime, the Math and Science Academy's cleaning team is using electrostatic sprayers to disinfect classrooms.

Hinton is hoping this outbreak is short-lived.

"Hopefully, between this pause and then the winter break happening ... by the time we come back in January, everyone will be healthy again," Hinton said.

The Centers for Disease Control and Prevention says flu shots reduce the risk of having to go to the doctor by anywhere from 40% to 60%. However, McMahon says we likely won't know how effectively it works this year until February.