Colorado Counties With The Highest Coronavirus Rates: Map

COLORADO — A new map compares coronavirus positivity rates in counties across the nation. Colorado is among the states with the lowest rates, but one county in our state — Prowers County — ranks among the worst positivity rates in the country, according to the report.

On Sept. 3, the Centers for Medicare & Medicaid Services published a dataset that shows COVID-19 test positivity rates in each U.S. county. A test positivity rate describes the percentage of tests conducted in a particular area that return a positive result. For example, if 1,000 people in a Colorado county are tested for COVID-19 in a particular week and 10 of those people test positive, the county would have a positivity rate of 1 percent. Meanwhile, if 25 people in a Colorado county are tested and 5 test positive, the test positivity rate for that county is 20 percent.

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The positivity rates are typically reported for a short period of time, either one day or one week, and are used to reflect a region’s testing capacity over time. If a region has a higher positivity rate, that likely means either many people there have COVID-19, the region does not have enough testing available to accurately measure its outbreak, or both. If a region has a lower positivity rate, on the other hand, that likely means a large share of the population has access to testing, and the region is diagnosing a more accurate share of its infected residents.

Test positivity rates are often used as an important indicator of how well a particular region is controlling its COVID-19 outbreak. The World Health Organization recommends a test positivity rate of 5 percent or lower — that figure, and a more lenient benchmark of 10 percent, have been adopted by school districts looking to reopen and states looking to restrict out-of-state visitors as a key threshold that must be met.

Stacker created the maps above by using the positivity rates reported by the Centers for Medicare & Medicaid Services. The figures reflect average weekly test positivity for the week of Aug. 27 to Sept. 2. Counties have been categorized according to their positivity rates:

• Green: test positivity under 5 percent in the past week (or with fewer than 10 tests in the past week)
• Yellow: test positivity between 5 percent and 10 percent in the past week
• Red: test positivity greater than 10 percent in the past week

The visualizations also include state-level positivity rates for the same time period, sourced from the COVID Tracking Project at The Atlantic, and county-level case and death counts from the most recent week of data available (Sept. 3 to Sept. 9), sourced from the New York Times COVID-19 data repository.

>> Read the Stacker article here.