A member of the Conifer High School system has tested presumptive positive for COVID-19, the disease caused by the new coronavirus, Jeffco Public Schools told families and staff Monday night.

“This means your child may have been exposed,” says a letter to families. “As a result, your child has been identified by Jefferson County Public Health as a person with a potential risk of contracting COVID-19, which warrants self-monitoring of symptoms.”

It’s unclear if the person who tested positive at Conifer High is a student or a staff member.

Conifer High is currently closed, as are the rest of Jeffco schools. Like most districts in the state, Jeffco closed its schools for several weeks, starting Monday, in response to coronavirus.

This is at least the second publicly reported case among a member of a school community in the Denver metro area. Previously, a staff member in the Brighton-based 27J Schools district north of Denver tested positive. Before widespread school closures were announced Thursday, Denver Public Schools had temporarily closed three schools after parents of students tested positive.

As of Monday, there are at least 160 presumed positive cases of COVID-19 in Colorado, but public health authorities believe the true number is much higher.

The Jefferson County public health department will contact Conifer High students determined to have had close contact with the person with COVID-19, the letter says. “If they determine your child has not been in direct contact with this person, you will not hear from them,” it says.

In addition, Conifer High will no longer serve as a meal distribution site. It had been among the eight schools where Jeffco Public Schools was distributing “grab and go” breakfast and lunch. That service started Monday and is set to continue at the other seven sites through March 27.