Mesa County was the canary in the COVID-19 coal mine, with the U.S. Centers for Disease Control and Prevention warning that the delta variant of the virus is adept the weak spots in our defenses and exploiting them.
It’s not clear whether quicker action in response to increasing cases and severe illnesses could have slowed delta’s nationwide takeover or avoided COVID-19 spikes in states with low vaccination rates. But the U.S. had a preview of what the summer would hold when Mesa County ran out of intensive-care beds roughly two months before the same thing would happen in parts of Texas.
The Centers for Disease Control and Prevention published a report Friday summarizing how delta took Mesa County by storm.
In only six weeks, from April 27 to June 6, more than one in every 100 people living in the county tested positive, including a higher-than-expected number of people who were fully vaccinated. Statewide, the number of cases compared to population was about half what Mesa County saw.
The Colorado Department of Public Health and Environment and the CDC sent teams to Mesa County in late June to investigate why Mesa County had higher-than-expected COVID-19 hospitalizations and more “breakthrough” cases among fully vaccinated people. They determined the delta variant was contributing to increased cases, hospitalizations, admissions to intensive-care units and deaths.
State epidemiologist Dr. Rachel Herlihy wrote in the report that while vaccination is the most important way to defeat delta, the Mesa County situation shows that wearing masks indoors and continued widespread testing will be important in areas with high numbers of cases.
Between late April and early June, the available vaccines were about 89% effective in the other Colorado counties — meaning that a vaccinated person had roughly one-tenth of an unvaccinated person’s likelihood of getting COVID-19. In Mesa County, the effectiveness dropped to 78%.
Delta now accounts for almost all new infections statewide, and in Mesa County, it’s not clear whether people’s immune systems were less able to identify and stop delta or whether the level of spread in the community gave the virus so many chances that it was bound to succeed more often.
The report did include one bit of good news. While nursing homes in Mesa County reported breakthrough cases, the overall odds that residents would get sick were low. In the majority of homes experiencing outbreaks, less than 2% of residents were infected — though in one facility, more than half were. The report didn’t specify if homes with lower vaccination rates had more cases.