Delta Plus Variants: Colorado Counties Where They're Spreading

The fight against COVID-19 has been complicated by the rise of the Delta variant, a more dangerous and transmissible mutation of the virus. But even this new strain isn't monolithic: There are now at least three additional versions of the Delta variant, collectively known as Delta Plus, and cases of them have been identified in 39 of Colorado's 64 counties.

Last week, the Colorado Department of Public Health and Environment announced numerous changes to the disease data it collects. Among other things, the CDPHE is now attaching the Greek letter corresponding to each variant. For instance, the original strain is labeled both "Alpha" and "B.1.1.7," its scientific name — and Beta, Epsilon and Gamma join Delta. Moreover, the department has supplemented Delta data with what are referred to as its "sublineages:" AY.1, AY.2 and AY.3, which we've simplified to Delta Plus 1, Delta Plus 2 and Delta Plus 3.

Are the three Delta Plus viruses riskier than Delta itself? Probably not — although the science isn't in. "Right now, there is no reason to believe that Delta Plus is going to pose any more challenge above and beyond Delta," Dr. Amesh Adalja, a senior scholar at the Johns Hopkins University Center for Health Security, told Healthline earlier this month. "But, obviously, we need more data to [know that] definitively."

What's certain is that the assorted Delta variants are now found throughout Colorado. CDPHE figures for the week of August 1, the most recent available, show that the Alpha virus accounted for just .61 percent of cases, with another .61 percent corresponding to other strains — presumably Beta, Epsilon and Gamma. In contrast, 85.02 percent of infections are related to the first Delta variant, .31 percent for Delta Plus 1, 1.22 percent for Delta Plus 2 and 12.23 percent for Delta Plus 3.

The department's "variants of concern" breakdown by county associates the Alpha virus with the most cases, but the collective Deltas are catching up fast — and Delta Plus 3 is leading the way among the sublineages. At 58, El Paso County, anchored by Colorado Springs, has the most Delta Plus 3 cases, followed by Larimer County (32), Denver County (28), Jefferson County (27), Arapahoe County (26), Adams County (25) and Weld County (19).

Many less populous counties have Delta Plus cases in the single digits — but as we've seen with the first Delta variant, totals can climb quickly. And these mutations of mutations suggest that even more variations could arrive in the months to come.

Here are the number of confirmed cases of Alpha, Beta, Epsilon, Gamma, Delta and the three Delta Plus viruses in the 39 Colorado counties where Delta Plus has been identified, listed in alphabetical order.

Adams County
Alpha: 1,161
Beta: 4
Epsilon: 172
Gamma: 59
Delta: 355
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 25

Alamosa County
Alpha: 33
Beta: 0
Epsilon: 2
Gamma: 0
Delta: 14
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 6

Arapahoe County
Alpha: 1,374
Beta: 10
Epsilon: 169
Gamma: 79
Delta: 547
Delta Plus 1: 0
Delta Plus 2: 3
Delta Plus 3: 26

Archuleta County
Alpha: 35
Beta: 0
Epsilon: 1
Gamma: 4
Delta: 59
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 2

Bent County
Alpha: 3
Beta: 0
Epsilon: 2
Gamma: 0
Delta: 0
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Boulder County
Alpha: 714
Beta: 0
Epsilon: 44
Gamma: 16
Delta: 329
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 12

Broomfield County
Alpha: 123
Beta: 0
Epsilon: 20
Gamma: 1
Delta: 54
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 4

Chaffee County
Alpha: 38
Beta: 15
Epsilon: 0
Gamma: 0
Delta: 7
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 2

Conejos County
Alpha: 22
Beta: 0
Epsilon: 0
Gamma: 1
Delta: 26
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 2

Crowley County
Alpha: 5
Beta: 0
Epsilon: 0
Gamma: 0
Delta: 2
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Delta County
Alpha: 15
Beta: 0
Epsilon: 13
Gamma: 0
Delta: 29
Delta Plus 1: 0
Delta Plus 2: 1
Delta Plus 3: 1

Denver County
Alpha: 1,145
Beta: 6
Epsilon: 230
Gamma: 81
Delta: 347
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 28

Douglas County
Alpha: 1,081
Beta: 4
Epsilon: 86
Gamma: 36
Delta: 290
Delta Plus 1: 0
Delta Plus 2: 1
Delta Plus 3: 16

Eagle County
Alpha: 67
Beta: 0
Epsilon: 30
Gamma: 16
Delta: 36
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 2

El Paso County
Alpha: 2,951
Beta: 2
Epsilon: 181
Gamma: 43
Delta: 1,269
Delta Plus 1: 0
Delta Plus 2: 8
Delta Plus 3: 58

Garfield County
Alpha: 185
Beta: 0
Epsilon: 19
Gamma: 4
Delta: 177
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 14

Grand County
Alpha: 17
Beta: 0
Epsilon: 6
Gamma: 3
Delta: 11
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Huerfano County
Alpha: 20
Beta: 0
Epsilon: 1
Gamma: 0
Delta: 1
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Jefferson County
Alpha: 954
Beta:11
Epsilon: 223
Gamma: 52
Delta: 374
Delta Plus 1: 0
Delta Plus 2: 1
Delta Plus 3: 27

La Plata County
Alpha: 272
Beta: 0
Epsilon: 16
Gamma: 3
Delta: 79
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 9

Larimer County
Alpha: 992
Beta: 0
Epsilon: 69
Gamma: 14
Delta: 213
Delta Plus 1: 0
Delta Plus 2: 1
Delta Plus 3: 32

Las Animas County
Alpha: 9
Beta: 1
Epsilon: 0
Gamma: 0
Delta: 38
Delta Plus 1: 0
Delta Plus 2: 3
Delta Plus 3: 2

Logan County
Alpha: 16
Beta: 0
Epsilon: 3
Gamma: 0
Delta: 10
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 2

Mesa County
Alpha: 320
Beta: 0
Epsilon: 53
Gamma: 12
Delta: 1,123
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 7

Mineral County
Alpha: 3
Beta: 0
Epsilon: 0
Gamma: 0
Delta: 2
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Montezuma County
Alpha: 56
Beta: 0
Epsilon: 5
Gamma: 0
Delta: 29
Delta Plus 1: 0
Delta Plus 2: 1
Delta Plus 3: 2

Montrose County
Alpha: 52
Beta: 0
Epsilon: 6
Gamma: 1
Delta: 67
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 4

Morgan County
Alpha: 31
Beta: 0
Epsilon: 3
Gamma: 0
Delta: 4
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Otero County
Alpha: 16
Beta: 0
Epsilon: 0
Gamma: 0
Delta: 4
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Ouray County
Alpha: 2
Beta: 0
Epsilon: 2
Gamma: 0
Delta: 5
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 2

Pitkin County
Alpha: 104
Beta: 0
Epsilon: 47
Gamma: 1
Delta: 37
Delta Plus 1: 0
Delta Plus 2: 1
Delta Plus 3: 3

Pueblo County
Alpha: 623
Beta: 1
Epsilon: 39
Gamma: 13
Delta: 178
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 12

Rio Blanco
Alpha: 16
Beta: 0
Epsilon: 20
Gamma: 0
Delta: 35
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 4

Rio Grande
Alpha: 14
Beta: 0
Epsilon: 0
Gamma: 3
Delta: 9
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

San Juan County
Alpha: 1
Beta: 0
Epsilon: 0
Gamma: 0
Delta: 8
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Sedgwick County
Alpha: 5
Beta: 2
Epsilon: 0
Gamma: 0
Delta: 3
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 2

Summit County
Alpha: 146
Beta: 0
Epsilon: 16
Gamma: 4
Delta: 134
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Washington County
Alpha: 1
Beta: 0
Epsilon: 0
Gamma: 0
Delta: 2
Delta Plus 1: 0
Delta Plus 2: 0
Delta Plus 3: 1

Weld County
Alpha: 1,016
Beta: 0
Epsilon: 41
Gamma: 18
Delta: 241
Delta Plus 1: 1
Delta Plus 2: 0
Delta Plus 3: 19