In this blog post, we want to provide key context for understanding the latest Case & Testing Data Dashboard additions that show rates of cases by patient vaccination status and COVID-19 variant cases. Federal, State and local mask recommendations for vaccinated and unvaccinated people are shifting rapidly in response to the impact of the Delta variant which is more easily spread than previous variants of COVID-19. The key takeaways of our new dashboard additions are:
- Twenty-eight day incidence rates of COVID-19 cases among unvaccinated residents are nearly twice as high as incidence rates among fully vaccinated residents.
- In some cases, fully vaccinated residents are experiencing one or more COVID-like symptoms, so vaccinated and unvaccinated residents should be getting tested if they experience COVID-like symptoms.
- Though Delta variant cases are still a small proportion of our overall variant cases in Pitkin County, we have seen more cases detected as Delta variants over recent weeks.
The current COVID-19 vaccinations are proving to be very effective at preventing hospitalization and death. However, like other vaccines, the COVID-19 vaccines are not 100% effective at preventing infection. As a result, we expect to see some COVID-19 cases among vaccinated people. Cases among fully vaccinated people are defined as a patient who tests positive for COVID-19 14 days or more after receiving their second dose of either the Pfizer or Moderna vaccine or a single dose of the Janssen (Johnson & Johnson) vaccine.
In order to track cases among fully vaccinated people, we have added the total number of cases among vaccinated Pitkin County residents since the beginning of 2021 to the top row of summary information (1).
Below the total fully vaccinated cases, we are reporting the percentage of all fully vaccinated residents that have tested positive for COVID-19 (1). The percentage is calculated as the number of fully vaccinated resident COVID-19 patients since April 15, 2021, divided by the total number of fully vaccinated residents to date. We chose this point in April because that is when we estimate that about half of our residents were fully vaccinated. Though we are seeing cases among vaccinated residents, the overall percentage of fully vaccinated cases among the fully vaccinated resident population continues to remain very low at 0.4%.
- Screenshot of the top row of summary information

Within the top panel, we have added daily cumulative 28-day incidence rates of cases among vaccinated and unvaccinated or partially vaccinated residents (2). We calculate the incidence rates among vaccinated residents by summing the number of cases over the 28 days prior to each daily estimate and divide that by the number of vaccinated residents beginning on March 1, 2021. We present this as a rate among 100,000 residents to provide estimates that are comparable to other Colorado counties and locations across the United States. We have selected a 28-day window to capture more cases, since we have had relatively low daily case counts since April of this year.
2. Screenshot of the incidence rates of COVID-19 cases among vaccinated and unvaccinated residents chart

The rates among unvaccinated residents is calculated similarly, with 28 day case counts among the unvaccinated residents divided by the total number of unvaccinated residents since March 1, 2021, presented as a 28 day count per 100,000 residents (2).
Currently, the incidence rate is approximately 2 times higher among unvaccinated residents as compared to vaccinated residents. These estimates highlight the importance of as many residents as possible getting vaccinated to reduce the risk of infection and continuing to keep our COVID-19 hospitalizations and fatalities low.
Recent evidence on COVID-19 spreading among vaccinated people has caused the CDC to update its recommendations for fully vaccinated individuals. CDC is now recommending that fully vaccinated individuals wear masks indoors in areas of high or substantial transmission. Pitkin County is currently considered by CDC as an area of high transmission.
Another way that we are capturing how vaccination is changing local characteristics of the pandemic is by adding the percentages of symptoms reported among vaccinated residents as compared to the symptoms of all our COVID-19 patients since March 2020 (3). The main purpose of displaying this data is to emphasize that our vaccinated residents should be tested even if they may only be experiencing one of these COVID-like symptoms.
3. Screenshot of symptoms among all cases and fully vaccinated cases chart

In the center panel, we have added a chart displaying the counts of COVID-19 cases by calendar week (4) and a second chart displaying weekly counts of resident cases that have been confirmed as variants since mid-February 2021 (5). This is the best way to track the increases in variants, including the Delta variant, and how they are impacting COVID-19 in Pitkin County.
4. Screenshot of total cases by calendar week chart

5. Screenshot of variant cases by week chart

Thanks for exploring these new data dashboard additions! Please reach out to us if you have any dashboard or data related questions or requests. Our goal is to provide our residents and visitors with the most up-to-date information on the COVID-19 situation in Pitkin County.
The best thing that each of us can do to improve our COVID-19 situation and protect our neighbors is to Get Vaccinated and continue to monitor Centers for Disease Control (CDC), Colorado Department of Public Health and Environment and Pitkin County Public Health recommendations.