Stopping short of requiring masks in schools and other indoor places, the local public health agency for Adams, Arapahoe and Douglas counties released a recommendation for wearing masks in those settings as the Delta variant continues “surging across the metro Denver area,” the agency said in a news release.

The Tri-County Health Department now recommends that “all persons wear masks in school settings regardless of vaccination status and, as long as we have rising rates of community transmission, that everyone including fully vaccinated persons wear a mask in public indoor settings,” the agency said in the July 30 release.

The decision to recommend — but not require — masks in schools leaves the question of whether to require masks up to individual school districts in Tri-County's area.

The Delta coronavirus variant spreads about twice as easily from one person to another as previous strains of the virus, according to Tri-County.

The recent recommendation from the federal Centers for Disease Control and Prevention for universal mask-wearing in school settings “is consistent with recent recommendations by the American Academy of Pediatrics and is based on the goal of keeping schools as safe as possible while maximizing in-person learning,” Tri-County's news release said.

Tri-County continued: “Wearing masks in indoor settings is an evidence-based, safe and effective way to prevent the spread of COVID-19, and mask-wearing in schools is particularly important because there are so many interactions in schools between vaccinated and unvaccinated people, and because children under 12 are not yet eligible to receive COVID-19 vaccines.”

In light of new data on the Delta coronavirus variant, the CDC in late July updated its guidance for fully vaccinated people. The CDC now recommends "universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status," according to its website.

The new CDC guidance applies to schools everywhere — and to other indoor settings in counties with “substantial transmission” of the virus, according to John Douglas, executive director of Tri-County Health.

Local cases on the rise

The CDC's change in guidance was based on surges in infection due to the Delta variant in many parts of the United States, as well as evolving understanding of vaccinated persons' ability to transmit Delta infection and slowing rates of vaccination, according to the Tri-County news release.

As of late July, similar to the rest of the metro area, all three Tri-County Health counties are in the CDC's “substantial” zone of transmission, with seven-day incidence rates — rates of new COVID-19 cases — above 50 cases per 100,000 people, according to Tri-County.

That means the new CDC guidance recommending that all people, vaccinated or not, wear masks in indoor settings applies in Tri-County's area.

Adams, Arapahoe and Douglas have seen the signs of an upswing in COVID-19 case rates, according to Tri-County's news release.

As of July 29, for Adams County, the seven-day incidence rate per 100,000 people for COVID-19 cases was 76 per 100,000. That represents an increase of 172% since June 26, according to the news release. Arapahoe has seen an incidence rate of 70 per 100,000, an increase of 142%, and Douglas had an incidence rate of 71 per 100,000, which is an increase of 163%, respectively, over the same period.

School districts must choose

Schools could return with little to no social distancing or mask requirements in August. The Colorado Department of Public Health and Environment released new K-12 school COVID-19 guidelines on July 20, but the new guidance “does not constitute statewide requirements,” a state news release said. Instead, the guidance outlines “best practices” for local governments and school districts.

Local health agencies, such as Tri-County, can decide for themselves whether to be stricter than the state and require precautions. But with Tri-County declining to require masks, the choice of whether to mandate masks falls to school districts.

Tri-County Health “has been working with our school districts to achieve optimal in-person learning and prevent transmission of COVID-19 and will continue to do so to help them understand how best to apply … new guidance,” the agency said in the news release. “Like much of the guidance released by the CDC, CDPHE and TCHD, for the 2021-22 school year, at this point, universal masking should be understood not as a requirement but as a strong science-based recommendation.”

How mask requirements had loosened in recent months

During a May 14 news conference, Gov. Jared Polis announced a relaxing of the statewide mask order, which after that point required masks unless people can prove they are vaccinated in settings such as prisons and jails, health care facilities, and schools.

The governor's mask executive order expired June 1, according to the governor's office, but its requirements generally lived on through an updated statewide public health order.

Colorado later released another updated public health order that removed state mask requirements for schools and repealed the mandate for school protocols regarding outbreaks and other instances of COVID-19 cases.

That updated order took effect July 1 and was set to expire on Aug. 1 unless extended.