Dean's Notes

The anticipated cold weather surge of the COVID-19 pandemic is challenging Colorado. This Sunday’s (November 22) number of Coloradans hospitalized for COVID-19 was 1,539, 70% above the April peak of 901, but a slight drop from the November 21 figure of 1,563. Continued increases in case numbers, hospitalizations, and deaths have been anticipated as transmission control has been declining and the effective reproductive number (R_E) has been increasing since mid-September. With R_E reaching 1.7 in recent weeks, and dropping to 1.4 last week, the epidemic curve has been rising sharply and exponentially.  

And now, the Thanksgiving holiday time is here. In the modeling work for the state, we have examined scenarios in which transmission control is reduced because of mixing during the holidays. Any additional relaxation, added onto the already rising epidemic curve, leads to even higher and earlier peaks for hospitalization, including the need for intensive care unit beds. Governor Polis continues to offer reminders of the risks of Thanksgiving gatherings and the Centers for Disease Control and Prevention (CDC) has cautioned against travel and recommends celebrating Thanksgiving with immediate family. Air travel has surged nonetheless, although the number of passengers is well below the 2019 figure and the number of people expected to drive to holiday destinations (48 million per the AAA) will be somewhat lower than last year. 

Not surprisingly, reactions to calls for small and restricted Thanksgiving holiday gatherings have been mixed. One Denver Post editorialist applied the term “draconian” to the Governor’s recommendations. The Los Angeles Times speaks to the need for resiliency as we deal with not gathering when we always do. A gathering via Zoom is a poor substitute for a shared meal, but far safer. With the anticipated availability of efficacious vaccines, next year’s holiday might be a return to normalcy.  

Last week’s modeling report provides updated estimates of transmission control by age group.  Disturbingly, transmission control continues to drop among those ages 20-39 years old, reaching 40%, i.e., only 40% of infectious contacts have been eliminated in that age group. Transmission control has been too low in this age group since mid-August, suggesting that contacts with younger adults may be a key driver of infection among those 40+. While young adults may have the misperception that they are unlikely to become ill with COVID-19, more than 100 persons age 20-39 are currently hospitalized. Fortunately, transmission control has increased among those 65+ over the last few weeks.  

Policy measures do limit transmission. The title of this New York Times article tells the story: “States That Imposed Few Restrictions Now Have the Worst Outbreaks.” Using an aggregate index for strength of containment measures, there is a clear inverse association between the rate of new cases and the strength of containment. Colorado is in the mid-range in the strength of its containment measures, with New Mexico having the tightest and South Dakota the weakest. Quoting another New York Times article: “Gov. Kristi Noem [Governor of South Dakota], a Republican, sees her approach as a badge of freedom, criticizing restrictions as ineffective and economically destructive.” For comparison to Colorado, South Dakota with a population of about 900,000 has 577 hospitalized with COVID-19 at present (about six-fold higher per capita than Colorado), reflecting yet another intersection of politics and the pandemic. 

The weeks after Thanksgiving will be telling, as we will learn where transmission control has settled with the opposing consequences of holiday travel and mingling, and of increased control measures for most Coloradans. Do your part and follow the guidance of our Governor and the CDC. Take a break and look forward to Thanksgiving 2021 and the prospect of herd immunity.