AURORA | There have been four more confirmed COVID-19 cases in the Cherry Creek School District since Monday, leading to 156 students and staff members at two high schools needing to quarantine.

All of the new cases are from Thursday, district spokesperson Abbe Smith said. At Cherry Creek High School, one student and one staff member tested positive for COVID-19. No quarantines were imposed stemming from the student’s case, but one staff member and 64 students who had been in contact with the staff member needed to quarantine.

At Grandview High School, two students tested positive for the virus, leading to the quarantine of nine staff members, one student athlete and 81 students. Smith could not immediately confirm whether the two cases were connected.

This is the second instance of COVID-19 at Cherry Creek High School, and the first at Grandview.

Since the beginning of the school year as Cherry Creek students returned to schools all or part time, a total of 21 COVID-19 cases have been identified among staff and students, resulting about 350 staff and students being quarantined or moved into online learning.

Information from the district shows that say 21 schools and programs in the Cherry Creek School District have now been impacted by COVID-19 cases, causing a range of quarantines and transfers.

“This is out of 55,000 students and 9,000 staff, which I think is important context for this,” Smith said in an email earlier in the week.

The rate of infection in Arapahoe County has steadily declined since the end of July. It now hovers at about 5% based on rolling averages provided by Tri-County Health Department. That reflects a 13% decrease in cases over the last 30 days.