BRECKENRIDGE — The Summit County Public Health Department is investigating an outbreak of six cases of the novel coronavirus at BHH Partners, an architecture firm in Breckenridge.

The outbreak is the third that the county has reported since Sept. 11 along with a spike of 35 cases in one week.

BHH Partners has temporarily closed its firm, according to the release. The department confirmed the first positive case on Sept. 18. Since then five more employees have tested positive, according to the release.

No clients of the firm have tested positive. All positive cases have been placed in isolation and all of their identified close contacts are in quarantine. The firm will reopen once isolation and quarantine requirements for the employees are complete.

While BHH Partners had been following proper public health protocols while clients were in the office, public health found that employees were not wearing masks when clients were not in the office. The firm also didn’t have procedures in place to screen employees for symptoms, according to the release.

On Sept. 10, employees held an after-work gathering at a restaurant while not wearing masks, according to the release.

The investigation of the outbreak is ongoing, as the county’s contact tracing team is still working to determine all the close contacts of the employees, according to the release.

An outbreak is defined by the Colorado Department of Public Health and Environment as two or more confirmed cases of COVID-19 in a facility or non-household group with onset in a 14-day period.