As Cherry Creek School District announced plans to bring back full-time in-person classes in middle and high schools, the district also said it told a high number of students and staff to quarantine during this semester.

Since the spring semester's start in January, the district alerted 4,066 students and staff to quarantine, according to a March 10 letter to the community from Superintendent Scott Siegfried. That number comes despite the fact that daily new COVID-19 cases in Arapahoe County have been declining for months.

The spring-semester quarantine number nears the district's total for essentially the entire first semester. From Aug. 14 through the fall semester, more than 3,900 students were told to quarantine, according to a report for a Dec. 14 Cherry Creek school board meeting. That represented about 7% of the district's roughly 55,000 students. In that same time, 553 staff members — about 6% — were told to quarantine.

Amid a steep climb in virus cases in Arapahoe County, the school district moved all students who attended in-person classes to online schooling in mid-November.

In the school year's first quarter specifically — through early October — the district told roughly 1,200 students and 150 staff members to quarantine.

The district sent letters alerting families about COVID-19 cases or observations of symptoms regarding dozens of schools and a couple of programs during the fall semester, according to the district's website. Each quarantine or other student dismissal triggers one letter sent by the district to families of students at the affected school. In that time, 236 letters were sent.

So far this semester — as of March 10 — the district has already sent 214 letters, according to its website. The district's third quarter ended on March 12.

In the fall semester, not all the letters announced quarantines — some cases were expected to have no impact on other students or staff. Eventually, the district changed its policy on letters to “only communicate regarding cases that have an impact on the school,” such as causing a quarantine.

The quarantine numbers for the current semester reached such high levels despite relaxed state guidance going into effect. Under an update to state guidance in November, as long as districts adhere to strict protocols, broad quarantines of classes or cohorts are no longer necessary regardless of the level of virus spread in a county.

School districts can now generally use “targeted contact identification,” which means quarantining those within 6 feet of a person with COVID-19 or symptoms of the disease for 15 minutes or more when both parties are masked. It also requires quarantines when someone was within 12 feet of the individual for 15 minutes or greater when either party was unmasked and indoors.

Cherry Creek district started using the targeted quarantines when students returned in January, said Abbe Smith, district spokeswoman.

The implementation of targeted quarantines has generally resulted in smaller groups of students being quarantined, per each quarantine, compared to before, according to Smith.

Explaining the numbers

Several factors may have contributed to the high number of students and staff quarantined this semester in comparison to the fall, Smith said.

"We were full remote for much of the second quarter due to the spike in COVID cases in Colorado and Arapahoe County at that time, so we would not have had any quarantines during that time," Smith said. "There were also fewer cases and quarantines at the start of the school year, building up to when we decided to switch to full remote in November and December."

John Douglas, head of Tri-County Health Department, speculated that Cherry Creek's third-quarter quarantine numbers have been high because of rates of virus transmission in the surrounding community remaining relatively high "though fortunately declining."

After the district started school in August, for the first several weeks, rates of virus cases were generally lower than they have been any time since, said Douglas, whose health agency covers Adams, Arapahoe and Douglas counties. Health officials think most quarantines result from virus spread in schools' communities, Douglas said.

Another difference this semester is the increased availability of COVID-19 testing, which could identify more cases and lead to more quarantines.

Starting in January, both Cherry Creek students and staff have had access to no-cost COVID tests through the district's partnership with an initiative called COVIDCheck Colorado. Students and staff at elementary school sites have had access to regular no-cost COVID testing to allow for early identification of COVID-positive children and adults who could also be asymptomatic.

Middle and high school students have been able to access no-cost COVID testing at either of the district's drive-up locations. Tests can be scheduled through school nurses.

But the breadth of testing accessed is unclear. The district generally does not track numbers or percentages of all students or staff who are tested, Smith said.

The district also offered free COVID-19 testing for all staff in the fall, but its number of staff members tested may have been less than 40% in September and early October, according to district data.

Approximately 50% of all the district's quarantined students have gotten tested for COVID-19 this semester, Douglas said.

It appears that testing of quarantined students specifically, though, may not account for many of the cases that trigger quarantines. Since the semester's start in January, of the 4,066 students and staff quarantined, only 17 individuals became knowingly COVID-positive during quarantine, Siegfried's March 10 letter to the community said.

Science still says schools relatively safe

With more metro Denver school districts returning to full-time in-person schooling — or close to it — Douglas thinks it's unlikely that the return will affect virus spread in the surrounding communities, especially because many teachers have been vaccinated.

“There haven't been too many reports where schools drive community transmission — it seems to be virtually the opposite,” Douglas said.

Douglas pointed to a recent report by the federal Centers for Disease Control and Prevention that reiterated that schools have low rates of COVID-19 transmission.

The information “has continued to reinforce that notion” that schools are safe, under the circumstances, if they adhere to safety precautions, Douglas said.