RUSSELL — Citing "extreme illness," Russell USD 407 will be closed Wednesday. The schools are seeing positive cases of both influenza A and B, as well as strep throat, said Superintendent Angela Lawrence.

The district already has sent parents a public service announcement asking them to keep sick children home and avoid crowds as much as possible in efforts to slow the spread of illness.

"Please keep your children home if they are running a fever and not feeling well," Lawrence said.

At the district's kindergarten and first-grade building, a total of 25 percent of students were out sick Tuesday. That number was 15 percent at the second through fifth-grade building.

The entire district had been running with 5 to 7 percent of the student body out for illness. On Monday, that number jumped to 11 percent, then 15 percent Tuesday, said Paula Bitter, the county health administrator.

"It has been a rough winter, and flu season can go through the end of May," Bitter said. "As rough as this one's been, it's like let's just stop everything now and try to get a handle on it before it gets worse."

The day off school likely won't be a complete fix, but hopefully could help slow the spread of illness, she said.

Russell's school calendar calls for the first Wednesday of the month to be a half-day for teacher inservice, so the decision was made to use the extra half-day sanitizing classrooms as a precaution, she said.

All athletic and extracurricular activities also will be canceled, and the town's public library will be closed Wednesday. The Dream Theatre and local churches also canceled activities this evening that revolve around students.

Bitter said officials still are encouraging all residents who are able to get a flu shot. Though not completely effective against current virus strains, it can help reduce the severity of symptoms, she said.

"Wash your hands frequently; use hand sanitizer if you can," Bitter said. "Stay home if you're sick. If your children are sick, keep your children home. The typical rule is you need to be fever-free for at least 24 hours without any aid from medication before coming back to school or work."