CALEDONIA TOWNSHIP, Mich. (WOOD) — On Friday, the parking lot at Caledonia High School was pretty much empty. Four students and one staff member were in quarantine, as classes switched from in-person to virtual.

The students had tested positive for COVID-19 and the staff member showed symptoms of the virus.

“Once we heard of the very first potential case, we followed our protocol and immediately contacted the Kent County Health Department,” said Caledonia Superintendent Dr. Dedrick Martin.

Martin says it appears the four students were infected before classes started earlier in the week, while at a social gathering where social distancing wasn’t practiced.

One didn’t attend the first day of school on Tuesday. Three others did.

The staff member is related to one of those students.

The health department has initiated contact-tracing efforts to figure out whether other students or faculty members were exposed.

The Caledonia Community Schools district isn’t the only Kent County district putting it’s coronavirus response to the test early on. In Grandville, parents of students under a staff member’s supervision at Grand View Elementary were contacted after an employee tested positive for COVID-19.

But Caledonia is the first to switch to at-home learning.

“It’s important that we pay attention to the recommendations from the Kent County Health Department and the CDC,” said Martin. “It’s important that we follow those recommendations.”

And in this case, the recommendation to go virtual may be temporary, depending on the results of contact tracing, to determine how widespread the exposure was.

It’s part of the game plan that Kent County school districts and the Kent County Health Department put together this summer, as they planned their pandemic return to class.

“That includes cohorting students. Keeping class sizes as low as possible for in person (learning). Communicating plans for student and parents to screen themselves at home, before they come to school if there are symptoms,” said Godfrey-Lee Public Schools Superintendent Kevin Polston.

Polston is also a member of Governor Whitmer’s Return to Learn Advisory Council. He says contact tracing is key to deciding whether in-person teaching should continue.

In the general population, a positivity rate of more than 3% on a seven-day average is cause for a larger concern.

“What we don’t have is that information by a school percentage, because we don’t test by school. We test across the county,” Polston said.

Officials take schools on a case-by-case basis. Tracing is narrowed to those who’ve been in close contact with someone who’s tested positive.

If you have been within 6 feet of a COVID-19-positive person for 15 minutes or more, you qualify as a close contact.

That information helps school and public health officials determine next steps.

“If it’s limited to a classroom, then is doesn’t make sense for an adjacent school to shut down, if we can contain it to a classroom,” Polston said. “It may not make sense for the school to close down if we can narrow it down to a classroom.”

Caledonia Community Schools said Friday the high school will be closed until Sept. 11. All learning will be done online.