Oak Mountain Middle School became the first school in Shelby County to reach a high absentee rate this school year, with 25 percent of its students missing from classrooms Wednesday.

Assistant Superintendent Tom Ferguson said the number has some parents concerned about the spread of the so-called “Swine Flu,” but he said the absentee rate doesn’t completely relate to the H1N1 virus.

“They’ve got a bunch of stuff going on over there,” Ferguson said. “I talked with the principal this morning and he said they’ve got it all.”

Almost 300 of the school’s 1,224 students were missing.

School system spokeswoman Cindy Warner said parents are reminded to watch their children closely. The system asks that students not return to school until 24 hours after symptoms subside.

“A lot of parents have said they’ve tried to call their doctors and make appointments, but doctors are asking them to stay home and are calling prescriptions in based on the symptoms,” Warner said.

Student Services Coordinator Donna Dickson said Shelby County School’s code of conduct does not require a doctor’s note for absences.

Ferguson, meanwhile, said the system is working on protocol for the possibility of school closures. He said it would be more likely to happen if staff began coming down with the virus, which hasn’t happened yet.

“To close school and feel like we have some sort of chance of getting everyone well, it would take a minimum of 12 days,” he said. “The CDC and the state health department say closing schools is no longer considered the best way to deal with the virus.”