With nearly one in five students out amid a flu outbreak, Uintah High School in Vernal has canceled its varsity football game for Friday as well as all other activities and practices through the weekend.

On Tuesday, 144 of the school's 1,150 students were absent. On Wednesday the number climbed to 192 students. And on Thursday, 245 students -- about 21 percent of the school's students -- were absent.

Principal Julie Wilde said she decided to cancel Friday's game against Spanish Fork High School and other activities after Uintah players started falling ill and the number of student absences at the school increased. A junior varsity football game was canceled Thursday.

"It's difficult because kids work hard, and coaches work hard and parents work hard to see their kids participate, but when I saw these numbers increase the way they have been, it just seemed very apparent to me we needed to err on the side of caution," Wilde said.

She said so far there's been no talk of cancelling classes because of the absences. The Centers for Disease Control and Prevention have recommended schools generally stay open as students report flu symptoms.

Wilde said of the 245 students who were absent Thursday, at least 97 said they stayed home because of flu-like symptoms, and those were just among the people who volunteered that reason. She said she is not yet aware of any confirmed cases of the H1N1 swine flu virus in the school. But doctors are not typically testing people for the virus unless they're seriously ill or need hospitalization.

Wilde said the school is recommending students stay home if they have a fever and a cough and stay home until they've been fever-free for 24 hours without medication.

She said the school has also canceled the volleyball team's trip to a tournament in Wyoming, a school business club's trip to an awards ceremony in Salt Lake City and practices for all activities and sports for today and Saturday.

This is the second football game in recent weeks that's been canceled because of illness. Recently, a Layton Christian Academy game against Gunnison Valley High School was canceled after many students called in sick, said Bart Thompson, assistant director of the Utah High School Activities Association.

"Obviously, we don't want any games canceled, but there are things more important than playing games," Thompson said. "The health and well-being of the students is of primary importance."

Uintah School District superintendent Mark Dockins said absenteeism is up across the district. He said he suspects parents are being extra cautious, keeping their children home if they're showing any symptoms of illness.

"Normally, people would encourage their kids to go [to school] if they have a sniffle, and right now they're taking this seriously," Dockins said. "They want to make sure their kids are safe, and they're not going to send them to school if their immune system is compromised by a cold. I'm certainly not going to fault any parents for doing that."

Wilde said absenteeism decreased Friday -- to 225 kids absent -- and she's hoping the weekend will further slow the spread of illness.

"Our numbers are getting better, so hopefully we'll be back on the mend on Monday," Wilde said.

The canceled football games have not yet been rescheduled.

What to do if you get sick

For a Centers for Disease Control and Prevention guide to seasonal and H1N1 swine flu symptoms and how to respond, visit http://www.cdc.gov/h1n1flu/sick.htm.