Coronavirus

The Real Story of Colorado COVID Breakthrough Cases

The emergency room entrance for St. Anthony Hospital in Lakewood.
The emergency room entrance for St. Anthony Hospital in Lakewood. Google Maps
One of the most hotly debated topics during the resurgence of COVID-19 involves breakthrough cases — infections of individuals fully immunized against the disease. But hard numbers for Colorado have been hard to come by, since public-health officials are understandably more focused on touting the effectiveness of vaccines than acknowledging that no medication is perfect.

At Westword's request, the Colorado Department of Public Health and Environment just provided a gusher of figures related to breakthrough cases and hospitalizations in the state, including a county-by-county rundown for April and May, the most recent period for which stats are available. It's the most extensive collection of state data that we've seen, and it demonstrates that the risk of breakthrough cases rises in areas with low vaccination rates.

In releasing the data, CDPHE officials concede, "We expect to see some vaccine breakthrough cases. This is similar to other vaccines; no vaccine provides 100 percent protection against infection, so breakthrough cases can occur."

However, the department stresses, "The vaccines are working well to prevent severe illness, hospitalization and death even when a fully vaccinated person contracts the virus that causes COVID-19. A large majority of cases, and an even larger majority of hospitalizations and deaths, occur among unvaccinated people. Because breakthrough cases can only occur in vaccinated individuals, we would expect to see some additional breakthrough cases as more Coloradans complete their vaccination series."


Because of a reporting lag, the department can't produce real-time statistics about breakthrough hospitalizations. But the number-crunchers were able to pull together information for the period between April 1 and June 30; over that span, 4,881 people were hospitalized in Colorado for COVID-19, and 4,612, or approximately 94.5 percent, were unvaccinated. That translates to 267 fully vaccinated people being hospitalized during that time, about 5.5 percent of the total over those three months.

The percentages are even more stark for confirmed COVID-19 cases. From April 1 to June 30, 80,039 of 83,302 cases, or 96.1 percent, involved unvaccinated people; breakthrough cases came to 3,263.

CDPHE-created graphics demonstrate that COVID-19 cases are much higher in counties with low vaccination rates, including Mesa, Garfield and El Paso. Here's the breakdown:
The scenario is even more extreme for hospitalizations:
The county breakthrough information covers the period between April 1 and June 1, and in many less populous counties, complete stats are not available. According to the CDPHE, "All N/A values have been suppressed in accordance with Colorado's data release policies."

This makes it impossible to determine the full situation regarding COVID-19 in counties such as Cheyenne, Hinsdale, Kiowa and San Juan, for which there are no numbers available at all related to both breakthrough cases and those among the unvaccinated. But in Mesa County, which has a low vaccination rate, breakthrough hospitalizations hit nearly 10 percent of the total of new cases. In contrast, in Denver, which has a much higher percentage of vaccinated residents, the number is closer to 5 percent: 27 breakthrough hospitalizations out of 443 total.

Not surprisingly, the CDPHE continues to encourage "all Coloradans over the age of twelve to get vaccinated as soon as possible to protect themselves, their families and their communities. Anyone who is unvaccinated is at greater risk and should continue wearing a mask, practicing social distancing and limiting gatherings with people outside of their household."

Here's the available data about breakthrough hospitalizations and cases for all 64 counties in Colorado between April 1 and June 1:

Adams
Hospitalizations, fully vaccinated: 22
Hospitalizations, total: 439
Cases, fully vaccinated: 234
Cases, total: 8,273

Alamosa
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 14
Cases, total: 328

Arapahoe
Hospitalizations, fully vaccinated: 35
Hospitalizations, total: 588
Cases, fully vaccinated: 337
Cases, total: 9,308

Archuleta
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 16
Cases, total: 276

Baca
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 39

Bent
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 60

Boulder

Hospitalizations, fully vaccinated: 9
Hospitalizations, total: 89
Cases, fully vaccinated: 132
Cases, total: 2,931

Broomfield

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 27
Cases, total: 692

Chaffee

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 24
Cases, total: 237

Cheyenne
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: N/A

Clear Creek
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 67

Conejos

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 41
Cases, total: 276

Costilla

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 48

Crowley

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 65

Custer
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 8,273

Delta

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 22
Cases, total: 402

Denver

Hospitalizations, fully vaccinated: 27
Hospitalizations, total: 443
Cases, fully vaccinated: 353
Cases, total: 8,645

Dolores

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 51

Douglas

Hospitalizations, fully vaccinated: 11
Hospitalizations, total: 252
Cases, fully vaccinated: 190
Cases, total: 5,503

Eagle

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 45
Cases, total: 544

El Paso

Hospitalizations, fully vaccinated: 27
Hospitalizations, total: 773
Cases, fully vaccinated: 412
Cases, total: 14,889

Fremont
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 43
Cases, total: 822

Garfield

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 62
Cases, total: 716

Gilpin

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 91

Grand

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 147

Gunnison

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 14
Cases, total: 133

Hinsdale

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: N/A

Huerfano

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 10
Cases, total: 95

Jackson

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 10

Jefferson

Hospitalizations, fully vaccinated: 31
Hospitalizations, total: 415
Cases, fully vaccinated: 313
Cases, total: 7,493

Kiowa

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: N/A

Kit Carson

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 53

La Plata

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 39
Cases, total: 723

Lake

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 5
Cases, total: 120

Larimer

Hospitalizations, fully vaccinated: 19
Hospitalizations, total: 290
Cases, fully vaccinated: 165
Cases, total: 4,607

Las Animas

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 5
Cases, total: 117

Lincoln

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 24

Logan

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 14
Cases, total: 190

Mesa

Hospitalizations, fully vaccinated: 15
Hospitalizations, total: 159
Cases, fully vaccinated: 234
Cases, total: 3,255

Mineral

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 7

Moffat
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 13
Cases, total: 274

Montezuma

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 16
Cases, total: 254

Montrose

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 30
Cases, total: 399

Morgan

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 9
Cases, total: 195

Otero

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 6
Cases, total: 184

Ouray

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 19

Park

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 181

Phillips

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 42

Pitkin
Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 8
Cases, total: 121

Prowers

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 107

Pueblo

Hospitalizations, fully vaccinated: 9
Hospitalizations, total: 269
Cases, fully vaccinated: 170
Cases, total: 3,169

Rio Blanco

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 90

Rio Grande

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 144

Routt

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 22
Cases, total: 94

Saguache

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 126

San Juan

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: N/A

San Miguel

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 5
Cases, total: 65

Sedgwick

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 6
Cases, total: 34

Summit

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 10
Cases, total: 339

Teller

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: 15
Cases, total: 438

Washington

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 24

Weld

Hospitalizations, fully vaccinated: 23
Hospitalizations, total: 340
Cases, fully vaccinated: 142
Cases, total: 5,121

Yuma

Hospitalizations, fully vaccinated: N/A
Hospitalizations, total: N/A
Cases, fully vaccinated: N/A
Cases, total: 70
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Michael Roberts has written for Westword since October 1990, serving stints as music editor and media columnist. He currently covers everything from breaking news and politics to sports and stories that defy categorization.
Contact: Michael Roberts