This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

DENVER (KDVR) — The U.S. Centers for Disease Control and Prevention’s list of Colorado counties with high or substantial rates of community transmission is growing quickly.

Last week the CDC released updated guidance about mask-wearing recommendations. In the new guidance, a county with a high or substantial rate of community transmission ought to have all its citizens in masks in public indoor spaces – vaccinated or not.

The CDC categorizes “high” community transmission as any location with a 7-day cumulative incidence rate of more than 100 cases per 100,000 as well as a test positivity percentage of 10%.

“Substantial” areas of community transmission applies to areas with between 50 and 99.99 cases per 100,000 and test positivity percentage of 8-9.99%.

At the time, about two-thirds of the state fell into either of these brackets. As of the morning of Aug. 4, more than four-fifths of the state’s counties qualify.

Only Bent, Crowley, Kiowa, Logan, Montezuma, Morgan, Otero, San Juan, Sedgwick, Washington and Yuma counties don’t make the cut.

The CDC’s guidelines, if implemented, would require masks for 98% of the state’s population.

State officials have not put new mask mandates in place, instead recommending them as wise for indoor gatherings. Locally, school districts including Denver Public Schools have begun putting their own mask requirements for teachers and students.