East Dayton Christian School said in a Facebook post that the athletic games scheduled for Friday night will still take place after the campus is cleaned and sanitized during the day.
No attendance figures were available from Centerville City Schools, and health officials have not announced any particular outbreak of flu cases in Centerville.
The district contacted parents and posted its decision to close around 5:15 p.m. on social media and on its website.
Wilmington City Schools made its decision to close late, posting that it was closed around 10:30 p.m. Thursday on its Facebook page.
“We are hopeful that this time will allow both staff and students to rest, get healthy, and be ready for school on Monday,” according to the social media message.
East Dayton Christian School announced the closure on its Facebook page on Wednesday.
Centerville High School parents waiting to pick up their kids Thursday afternoon spoke to News Center 7's Monica Castro about the large number of illnesses, and one parent has a child who has been out of school for about four days.
While it’s not uncommon for the cold or flu to run rampant this time of year, it has hit Centerville City Schools hard.
“Yesterday, half my government class was out. I have five classes, six classes and three of my teachers were sick today,” junior Emily Hardy said.
MORE: Montgomery County has most flu-like cases in state
“Some teachers have to cover other teachers’ rooms. We saw the principal cover an extra classroom. It was weird,” sophomore Sydney Mates said.
Her mother, Darlene Henn, said she’s heard that hundreds of students districtwide have been affected by an illness.
“Yesterday, the gossip was that a thousand students and teachers were out in the district,” Henn said.
One parent shared a voicemail received previously from Centerville High School about a bug going around.
"Good evening, this is John Carroll, the principal of Centerville High School, just calling with this message from our school nurse. Students who are ill with flu-like symptoms should remain home for at least 24 hours after they've been symptom free, free of fever or signs of fever."
The flu season runs from October through May, and activity is considered widespread in Ohio.
Hospitalizations in Montgomery County normally peak the last week of December and the first few weeks of January, according to county data. As of Jan. 19, there had been 405 Montgomery County flu-related hospitalizations.
One child has died in Ohio from the flu this season, while adult flu-related deaths are not tracked.
Henn said she equipped her daughter with some supplies this week to help her stay healthy.
“I sent my daughter to school with four bottles of Lysol and anti-bacterial lotion this week,” she said.
Along with sanitizer, Mates said, “I’ve been taking Vitamin C so I don’t think I’ll get sick. It is a concern, but I think I’ll be OK.”
MORE: Health officials urge residents to get flu shot
Symptoms of influenza can include fever, cough, sore throat, body aches, headache, chills and fatigue.
In addition to getting a flu shot, the Ohio Department of Health recommends washing your hands often with soap and water or use alcohol-based sanitizer when unable to wash, trying not to touch your eyes, nose or mouth because germs are often spread this way, getting plenty of rest, and when you are sick, stay home until you are fever-free for 24 hours without any fever-reducing medications.