About 20 fifth graders were affected by nausea on Thursday at Sugar Creek Elementary School in Limestone County, according to Superintendent Randy Shearouse.

And while school officials are working to determine what happened, Shearouse said the children did not ingest raw chicken tenders.

“The box says ‘fully cooked,’” he said. “They come to us fully cooked.”

One student was hospitalized following lunch at the school in Lester on Thursday. Shearouse said many of the students who complained of nausea after lunch were at school today.

All of the students affected were fifth graders, he said. Sugar Creek Elementary has an enrollment of 576 students, from kindergarten through fifth grade.

“We are going to test the food to see if we can determine if this was as anything related to what we serve,” he said. “They do have to save food samples of what we serve so it can be tested.”

Shearouse said certain aspects of the incident do not initially sound like food poisoning.

“The health department shared with us that normally food poisoning takes four to six hours,” he said. “This was a lot quicker than that. That kind of causes us to pause. We don’t know if this was a virus going around, something related to food. We’re just not sure at this point.”

According to the Centers for Disease Control, some germs can make a person sick within a few hours after ingesting them, while others may take a few days. Staph food poisoning, though, can appear as quickly as 30 minutes after eating.

“As a school system, we have very strict standards in terms of serving food,” he said. “Very seldom does it happen, but we have procedures in place to identify anything on our end. School lunchrooms are very clean and safe, and usually get very high inspection scores.”