WILTON — A member of the Cider Mill School community has tested positive for COVID-19, Superintendent of Schools Kevin Smith said Friday.

The announcement, in a letter to parents and other members of the school community, came one day after telling the Wilton Board of Education the district was fortunate to have had only two cases since school reopened. The first was on Sept. 11 and the second about two weeks ago. Both involved Wilton High School.

In this instance, Smith announced contact tracing has taken place and “the specific people impacted will be on remote learning or self-monitoring for 14 days.” School administrators are reaching out to those who had “close contact” with the individual and they are being directed to quarantine for 14 days, he said.

Those who were not in close contact, but were in classrooms or other spaces with the individual are being contacted and told to self-monitor for any symptoms, he said.

Citing privacy, Smith declined to give any further information, including how many individuals were affected.

The district’s four schools — Miller-Driscoll, Cider Mill, Middlebrook and Wilton High School — will operate as planned. Students have returned to full, in-person learning four days a week at Miller-Driscoll and Cider Mill, which together serve kindergarten through fifth grade. Middlebrook and the high school continue to operate on a hybrid model.

A significant uptick in the number of positive COVID cases in Wilton over the past two weeks caused Smith to delay plans to return the entire student body to Middlebrook School for in-person learning four days a week. The Board of Education had expected to vote on the students’ return at its meeting on Thursday.

There have been 14 new cases of the coronavirus in Wilton reported by the state Department of Public Health since Oct. 11, and the town is now one of three Fairfield County municipalities that are considered by the state as “yellow alert” communities with 5 or more cases per 100,000 residents. Stamford has 8.9 cases per 100,000, Easton is at 5.7, and Wilton is at 5.4 cases.