Eighty K-12 schools in Colorado had active COVID-19 outbreaks as of Wednesday — nearly double the 42 outbreaks reported last week.

And last week's total number of school outbreaks was more than double the preceding week.

The Colorado Department of Public Health and Environment reported 291 active outbreaks on Wednesday, up from 242 a week earlier.

Schools accounted for the majority of that increase, with most other settings holding steady and single-digit rises in the number of nursing homes and correctional facilities reporting clusters. Any increase in nursing home outbreaks is potentially worrisome, though, because residents accounted for a disproportionate share of deaths in previous waves.

About two-thirds of the school-based outbreaks involved fewer than 10 cases, though almost a dozen affected 20 or more people.

The Colorado schools with the largest outbreaks are:

  • Douglas County High School, Douglas County School District: 27 students and seven staff cases
  • Power Technical Early College, District 49: 28 students, six staff
  • Mesa Middle School, DCSD: 28 students, five staff
  • Elbert School, Elbert School District 200: 21 students, 11 staff
  • Horizon Middle School, District 49: 28 students, four staff
  • STEM School Highlands Ranch, DCSD: 30 students
  • Naturita Elementary School, West End Public Schools: 24 students, two staff
  • Legacy Academy, Elizabeth School District: 20 students, five staff
  • Cimarron Middle School, DCSD: 21 student, one staff
  • Remington Elementary School, District 49: 21 students, one staff
  • Sagewood Middle School, DCSD: 18 students, two staff

The 80 school outbreaks have affected a combined 760 students and 126 staff members. So far, no deaths have been linked to the current clusters.

At the worst point, in early December, 211 schools had outbreaks. At that time, the state still defined a school outbreak as two or more linked cases, but now only clusters of five or more cases are reported, so it's not clear how the current situation would compare if schools used the lower cut-off.

Last fall, outbreaks popped up more slowly. It took until early November to reach the current number of outbreaks, even with the lower threshold to declare one. Of course, nearly all schools required masks then, and more students were learning from home.

The data isn't comprehensive, because a school is only considered to have an outbreak if five or more cases are linked by a common class, activity or bus route. The state considers outbreaks active until four weeks have passed with no new cases.

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