WILTON — After five positive cases of COVID-19 at Cider Mill School were discovered — three on Nov. 4, one on Nov. 8, and one on Nov. 9 — 92 students across the district have been quarantined, according to a letter from Superintendent of Schools Kevin Smith on Monday.

In addition, 18 staff members have also been quarantined, he said. All were found to be in direct contact with someone who had tested positive for the illness.

As of Monday, Smith said two staff members at Cider Mill, one at Miller-Driscoll, and one district-level staffer have tested positive and are isolating. The district-level staffer’s diagnosis was also discovered Monday.

There are also four Cider-Mill students who tested positive and are isolating.

“We are concerned about the significant increase in cases in our schools and in our larger, Wilton community,” Smith said. “We’ve shared this information with our local health professionals and plan, for the time being, to remain in the learning models we are currently utilizing. Given updated recommendations or additional quarantines, we may find ourselves needing to shift models.”

According to the district, here are the number of staff members quarantined:

 Wilton High School — 2

 Cider Mill — 10

 Miller-Driscoll — 4

 District — 2

No Middlebrook staff members are affected.

Students affected are:

 Wilton High School — 4

 Middlebrook — 3

 Cider Mill — 60

 Miller-Driscoll — 25

Smith said the district believes the positive cases were not a result of in-school transmission, although several cases are known to be the result of youth sporting events and family transmission.

The school has conducted contact tracing and after consulting with town Health Director Barry Bogle, determined people who were directly affected will be quarantined, remote learning and self-monitoring for 14 days.

“Due to the nature of this case, we have now also advised all Cider Mill students and staff to self-monitor for symptoms in the event that they came in contact with a person who came in contact with the COVID-positive individual,” Smith said in an earlier letter on Sunday.

Self-monitoring means taking one’s temperature every morning, something everyone should be doing during this pandemic, he said.

Smith reviewed the district’s protocols for dealing with positive cases of COVID-19.

Those who test positive should isolate at home for a minimum of 10 days from the date of a positive test. Once those 10 days are up, the affected person may resume normal activities when 24 hours have passed with no fever without the use of fever-reducing medications and other symptoms of COVID-19 are improving, his letter said.

He also referred people to the CDC website for more information about the isolation period for COVID-positive individuals.

Those who have come in contact with a COVID-positive person while they were sick or within 48 hours before a positive test or the onset of symptoms, should quarantine for 14 days. Members of their household should monitor for symptoms, but they may continue normal activities including going to school.