Fulton County Schools took the initiative last week when it became the first Georgia school district to shut down temporarily in reaction to the spreading coronavirus, but a new confirmed case in a high school illustrates the risk of relaxing too soon.

The state’s fourth largest school district announced Sunday afternoon that an employee at Banneker High has been confirmed to be infected with the virus, which causes the disease COVID-19. The disease, now a global pandemic, has so far been less harmful for youths than for older adults.

The district, which closed Tuesday and Wednesday, reopened Thursday. That is when the employee who was subsequently diagnosed came into contact with students and staff, district spokesman Brian Noyes said. The employee disclosed feeling ill on Friday while at Banneker for a teacher work day when the school was closed to students, Noyes said. The district has talked with the employee about whom he or she may have been in contact with and has shared the information with Fulton County public health officials, he said.

All at the school have been notified, and the high-risk individuals will be contacted by health workers, Noyes said. “We basically notified them to let them know that public health will be reaching out to provide guidance.”

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The district was the focus of attention in Georgia on Monday when it called a hasty news conference to announce it was temporarily closing all schools, affecting about 94,000 students. The decision was made after a teacher who worked at two middle schools on the county’s south side — Bear Creek and Woodland — was diagnosed with the disease. (The two middle schools are within 10 miles of Banneker but are not within its attendance zone.) All schools needed to be cleaned and disinfected, the district said.

Then, on Wednesday, the district announced that a second employee, this time at Woodland Middle School, had been diagnosed.

Noyes said that as far as he knows all three employees are fairing well. He said privacy laws prohibit disclosure of details about the latest case, such as the employee’s gender and whether he or she is a teacher.

Banneker High, southwest of Hartsfield-Jackson Atlanta International Airport just outside Union City, is among six sites the school district identified as food distribution centers for students in the U.S. Department of Agriculture's federally-subsidized school meal program.

It will remain a distribution site despite this latest case, after it is cleaned and disinfected Sunday.

Like most school districts in Georgia, Fulton has now closed its schools for an extended period, in this case until further notice. As of Sunday afternoon, the Georgia Department of Education was counting Fulton among more than 130 of the state's 180 school districts that had taken such action, affecting more than 1.4 million students. The closures were most common in the northern and southwestern parts of the state, with many central Georgia and coastal school districts choosing to remain open, for now.

School districts and public colleges started closing in quick succession after Gov. Brian Kemp on Thursday suggested it, issuing a "call for action" for local officials to shut down for two weeks if they felt it to be "prudent."

The USDA then issued waivers allowing Georgia schools to continue feeding students on subsidized school meal plans during the closures, and Fulton and other districts began publicizing their meal distribution plans and locations.