TABLE 3. Characteristics of hospitalizations with COVID-19–like illness,* by mRNA COVID-19 vaccination status† and SARS-CoV-2 test result — 10 states, August 2021–January 2022§.
| Characteristic | Total, no. (column %) | mRNA
COVID-19 vaccination status,
no. (row %) |
SMD** | Positive SARS-CoV-2 test result, no. (row %) | SMD** | |||
|---|---|---|---|---|---|---|---|---|
| Unvaccinated | 2 doses (<180 days earlier) | 2 doses (≥180 days earlier) | 3 doses¶ | |||||
|
All
hospitalizations
|
87,904 (100)
|
37,860 (43)
|
14,760 (17)
|
26,678 (30)
|
8,606 (10)
|
—
|
18,237 (21)
|
—
|
|
Variant
predominance period
| ||||||||
| B.1.617.2 (Delta) |
86,327 (98)
|
37,400 (43) |
14,645 (17) |
26,190 (30) |
8,092 (9) |
0.08 |
17,939 (21) |
–0.02 |
| B.1.1.529 (Omicron) |
1,577 (2)
|
460 (29) |
115 (7) |
488 (31) |
514 (33) |
298 (19) |
||
|
Sites
| ||||||||
| Baylor Scott & White
Health |
15,226 (17)
|
7,730 (51) |
2,180 (14) |
4,372 (29) |
944 (6) |
0.56 |
2,462 (16) |
0.51 |
| Columbia University |
3,254 (4)
|
1,372 (42) |
696 (21) |
975 (30) |
211 (6) |
331 (10) |
||
| HealthPartners |
1,159 (1)
|
265 (23) |
374 (32) |
450 (39) |
70 (6) |
133 (11) |
||
| Intermountain Healthcare |
8435 (10)
|
4283 (51) |
1158 (14) |
2201 (26) |
793 (9) |
3117 (37) |
||
| Kaiser Permanente Northern
California |
22,181 (25)
|
4,891 (22) |
4,691 (21) |
8,591 (39) |
4,008 (18) |
2,716 (12) |
||
| Kaiser Permanente
Northwest |
3,879 (4)
|
1,628 (42) |
927 (24) |
961 (25) |
363 (9) |
740 (19) |
||
| Regenstrief Institute |
23,370 (27)
|
12,641 (54) |
3,134 (13) |
6,274 (27) |
1,321 (6) |
6,686 (29) |
||
| University of Colorado |
10,400 (12)
|
5,050 (49) |
1,600 (15) |
2,854 (27) |
896 (9) |
2,052 (20) |
||
|
Age group,
yrs
| ||||||||
| 18–49 |
21,128 (24)
|
13,609 (64) |
3,980 (19) |
2,780 (13) |
759 (4) |
0.63 |
5,523 (26) |
0.31 |
| 50–64 |
20,193 (23)
|
10,204 (51) |
4,407 (22) |
4,407 (22) |
1,175 (6) |
5,132 (25) |
||
| 65–74 |
19,798 (23)
|
6,952 (35) |
3,283 (17) |
7,052 (36) |
2,511 (13) |
3,684 (19) |
||
| 75–84 |
17,052 (19)
|
4,647 (27) |
2,122 (12) |
7,609 (45) |
2,674 (16) |
2,626 (15) |
||
| ≥85 |
9,733 (11)
|
2,448 (25) |
968 (10) |
4,830 (50) |
1,487 (15) |
1,272 (13) |
||
|
Sex
| ||||||||
| Male†† |
39,602 (45)
|
17,468 (44) |
6,131 (15) |
11,969 (30) |
4,034 (10) |
0.04 |
9,252 (23) |
–0.14 |
| Female |
48,302 (55)
|
20,392 (42) |
8,629 (18) |
14,709 (30) |
4,572 (9) |
8,985 (19) |
||
|
Race/Ethnicity
| ||||||||
| White, non-Hispanic |
56,669 (64)
|
23,297 (41) |
8,855 (16) |
18,333 (32) |
6,184 (11) |
0.25 |
11,743 (21) |
0.17 |
| Black, non-Hispanic |
9,628 (11)
|
5,026 (52) |
1835 (19) |
2,240 (23) |
527 (5) |
1,707 (18) |
||
| Hispanic |
11,304 (13)
|
5,337 (47) |
2,171 (19) |
2,955 (26) |
841 (7) |
2,585 (23) |
||
| Other,
non-Hispanic§§ |
5,488 (6)
|
1,524 (28) |
1,232 (22) |
1,940 (35) |
792 (14) |
808 (15) |
||
| Unknown |
4,815 (5)
|
2,676 (56) |
667 (14) |
1,210 (25) |
262 (5) |
1,394 (29) |
||
|
Chronic
respiratory condition¶¶
| ||||||||
| Yes†† |
57,225 (65)
|
24,037 (42) |
9,549 (17) |
17,693 (31) |
5,946 (10) |
–0.06 |
11,648 (20) |
0.03 |
| No |
30,679 (35)
|
13,823 (45) |
5,211 (17) |
8,985 (29) |
2,660 (9) |
6,589 (21) |
|
|
|
Chronic
nonrespiratory condition***
| ||||||||
| Yes†† |
74,943 (85)
|
29,810 (40) |
12,787 (17) |
24,270 (32) |
8,076 (11) |
–0.32 |
13,924 (19) |
0.30 |
| No |
12,961 (15)
|
8,050 (62) |
1,973 (15) |
2,408 (19) |
530 (4) |
4,313 (33) |
||
|
Vaccine
product
| ||||||||
| Moderna |
20,236 (40)
|
— |
5,690 (28) |
11,903 (59) |
2,643 (13) |
— | 1,294 (6) |
0.15 |
| Pfizer-BioNTech |
29,418 (59)
|
— |
9,023 (31) |
14,740 (50) |
5,655 (19) |
2,480 (8) |
||
| Combination of mRNA products | 390 (1) | — | 47 (12) | 35 (9) | 308 (79) | 17 (4) | ||
Abbreviations: ED = emergency department; SMD = standardized mean or proportion difference; UC = urgent care.
* Medical events with a discharge code consistent with COVID-19–like illness were included. COVID-19–like illness diagnoses included acute respiratory illness (e.g., COVID-19, respiratory failure, or pneumonia) or related signs or symptoms (cough, fever, dyspnea, vomiting, or diarrhea) using diagnosis codes from the International Classification of Diseases, Ninth Revision and International Classification of Diseases, Tenth Revision. Clinician-ordered molecular assays (e.g., real-time reverse transcription–polymerase chain reaction) for SARS-CoV-2 occurring ≤14 days before to <72 hours after admission were included. Recipients of Janssen, 1 or >3 dose of an mRNA vaccine, and those for whom 1–13 days had elapsed since receipt of any dose were excluded.
† Vaccination was defined as having received the listed number of doses of an mRNA-based COVID-19 vaccine ≥14 days before the medical event index date, which was the date of respiratory specimen collection associated with the most recent positive or negative SARS-CoV-2 test result before the medical event or the admission date if testing only occurred after the admission.
§ Partners contributing data on medical events and estimated dates of Omicron predominance were in California (December 21), Colorado (December 19), Indiana (December 26), Minnesota and Wisconsin (December 25), New York (December 18), Oregon (December 24), Texas (December 16), Utah (December 24), and Washington (December 24). The study period began in September 2021 for partners located in Texas.
¶ The “3 doses” category includes persons who have received a third dose in their primary series or received an additional dose following their 2-dose primary series; this includes the reduced-dosage Moderna booster.
** An absolute standardized mean or proportion difference ≥0.20 indicates a nonnegligible difference in variable distributions between medical events for vaccinated versus unvaccinated patients. First, a single SMD was calculated by averaging pairwise comparisons of each vaccinated category versus unvaccinated, and then, a second SMD was calculated separately for SARS-CoV-2–positive versus SARS-CoV-2–negative patients. For example, the age SMD calculation comparing unvaccinated versus different vaccinated categories was generated by averaging the pairwise SMD calculations for unvaccinated and 2 doses (<180 days earlier), unvaccinated and 2 doses (≥180 days earlier), and unvaccinated and 3 doses.
†† Indicates the reference group used for standardized mean or proportion difference calculations for dichotomous variables.
§§ Other race includes Asian, Hawaiian or Other Pacific islander, American Indian or Alaska Native, Other not listed, and multiple races.
¶¶ Chronic respiratory condition was defined as the presence of discharge code for asthma, chronic obstructive pulmonary disease, or other lung disease using diagnosis codes from the International Classification of Diseases, Ninth Revision and the International Classification of Diseases, Tenth Revision.
*** Chronic nonrespiratory condition was defined as the presence of discharge code for heart failure, ischemic heart disease, hypertension, other heart disease, stroke, other cerebrovascular disease, diabetes type I or II, other diabetes, metabolic disease, clinical obesity, clinically underweight, renal disease, liver disease, blood disorder, immunosuppression, organ transplant, cancer, dementia, neurologic disorder, musculoskeletal disorder, or Down syndrome using diagnosis codes from the International Classification of Diseases, Ninth Revision and the International Classification of Diseases, Tenth Revision.