COVID Levels in Colorado
In the week ending 10 October 2026, wastewater virus levels in Colorado were High or Very High for COVID-19 at 2 of 23 sites, Flu A at 1 of 22 sites, RSV at 0 of 23 sites. COVID-19 was High or Very High at 9% of the state's sampling sites. Source: CDC wastewater surveillance.
Very High High Moderate Low Very Low
Sampling sites in Colorado 23
| Counties served | People served | COVID-19 | Flu A | RSV |
|---|---|---|---|---|
| Denver | 709,904 | Low | Very Low | Very Low |
| El Paso | 406,059 | Low | Very Low | Very Low |
| Jefferson | 345,454 | Low | Very Low | Very Low |
| Adams, Arapahoe | 268,004 | Low | Very Low | Very Low |
| Arapahoe | 247,443 | Low | Very Low | Very Low |
| Pueblo | 96,515 | Very Low | Very Low | Very Low |
| Larimer | 92,127 | Moderate | Very Low | Very Low |
| Boulder | 89,383 | Low | Very Low | Very Low |
| Mesa | 89,286 | High | Very High | Very Low |
| Weld | 83,319 | Moderate | Very Low | Very Low |
| Routt | 43,741 | Low | Very Low | Very Low |
| Adams | 40,071 | Moderate | Very Low | Very Low |
| Summit | 35,643 | High | Very Low | Very Low |
| Douglas | 35,000 | Low | Very Low | Very Low |
| Montrose | 30,857 | Moderate | — | Very Low |
| Otero | 29,643 | Low | Very Low | Very Low |
| Summit | 28,571 | Low | Very Low | Very Low |
| Douglas | 25,000 | Moderate | Low | Very Low |
| La Plata | 23,429 | Low | Very Low | Very Low |
| Alamosa | 18,364 | Low | Very Low | Very Low |
| Garfield | 16,714 | Very Low | Very Low | Very Low |
| San Miguel | 15,000 | Moderate | Very Low | Very Low |
| Pitkin | 5,500 | Moderate | Very Low | Very Low |
When levels are high where you live
- Stay current on vaccines for COVID-19 and flu, and RSV if you are 75+, 50–74 with risk factors, pregnant, or have an infant.
- Test if you have symptoms; antivirals for COVID-19 and flu work best in the first days and are meant for people at higher risk.
- A well-fitting mask in crowded indoor places and better ventilation cut the risk for you and for people around you.
- Stay home when sick. Outbreak news is in our epidemic record.
What this page shows, and what it misses
CDC's weekly wastewater viral activity level for each sampling site — a treatment plant or a point upstream — compared with that site's own baseline, in five categories from Very Low to Very High. State rows count sites; CDC's own state level, on its map, weighs sites differently and can differ from what these counts suggest. Places not on a sewer system, and sites that did not report this week, are not covered. Wastewater shows community spread, not the number of cases.
Data: Centers for Disease Control and Prevention, National Wastewater Surveillance System, "CDC Wastewater Viral Activity Level for SARS-CoV-2, Influenza A and RSV" (data.cdc.gov) — public domain U.S. Government work.