TABLE 3. Characteristics of hospitalizations among adults aged ≥18 years with COVID-19–like illness,* by Omicron subvariant–predominant period, mRNA COVID-19 vaccination status, and SARS-CoV-2 test result — 10 states, December 2021–June 2022.
| Characteristic | Total no. (column %) | mRNA COVID-19 vaccination status, no. of doses received¶ |
Positive test result* |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|
| No. (row %) |
SMD** | No. (row %) | SMD** | |||||||
| Unvaccinated | Days since last dose |
4 doses |
||||||||
| 2 doses |
3 doses |
|||||||||
| 14–149 | ≥150 | 7–119 | ≥120 | ≥7 | ||||||
|
Omicron BA.1–predominant period† | ||||||||||
|
All hospitalizations
|
35,399 (100.0)
|
14,742 (41.6) |
1,236 (3.5) |
8,850 (25.0) |
9,146 (25.8) |
1,425 (4.0) |
N/A |
— |
10,534 (29.8) |
— |
|
Site
| ||||||||||
| Baylor Scott& White Health |
8,697 (24.6)
|
4,480 (51.5) |
324 (3.7) |
2,528 (29.1) |
1,190 (13.7) |
175 (2.0) |
— |
0.551 |
2,904 (33.4) |
0.218 |
| Columbia University |
1,419 (4.0)
|
668 (47.1) |
94 (6.6) |
367 (25.9) |
274 (19.3) |
16 (1.1) |
— |
536 (37.8) |
||
| HealthPartners |
1,334 (3.8)
|
378 (28.3) |
40 (3.0) |
262 (19.6) |
586 (43.9) |
68 (5.1) |
— |
322 (24.1) |
||
| Intermountain Healthcare |
3,224 (9.1)
|
1,159 (35.9) |
148 (4.6) |
701 (21.7) |
985 (30.6) |
231 (7.2) |
— |
756 (23.4) |
||
| KPNC |
6,911 (19.5)
|
1,501 (21.7) |
219 (3.2) |
1,748 (25.3) |
3,036 (43.9) |
407 (5.9) |
— |
1,940 (28.1) |
||
| KPNW |
1,480 (4.2)
|
539 (36.4) |
56 (3.8) |
288 (19.5) |
478 (32.3) |
119 (8.0) |
— |
360 (24.3) |
||
| PHIX |
96 (0.3)
|
64 (66.7) |
1 (1.0) |
19 (19.8) |
11 (11.5) |
1 (1.0) |
— |
45 (46.9) |
||
| Regenstrief Institute |
8,980 (25.4)
|
4,398 (49.0) |
276 (3.1) |
1,969 (21.9) |
2,076 (23.1) |
261 (2.9) |
— |
2,937 (32.7) |
||
| University of Colorado |
3,258 (9.2)
|
1,555 (47.7) |
78 (2.4) |
968 (29.7) |
510 (15.7) |
147 (4.5) |
— |
734 (22.5) |
||
|
Age group, yrs
| ||||||||||
| 18–49 |
6,621 (18.7)
|
4,057 (61.3) |
392 (5.9) |
1,304 (19.7) |
812 (12.3) |
56 (0.8) |
— |
0.540 |
1,981 (29.9) |
0.126 |
| 50–65 |
7,783 (22.0)
|
3,847 (49.4) |
328 (4.2) |
2,008 (25.8) |
1,470 (18.9) |
130 (1.7) |
— |
2,664 (34.2) |
||
| 65–74 |
8,073 (22.8)
|
3,059 (37.9) |
233 (2.9) |
2,041 (25.3) |
2,325 (28.8) |
415 (5.1) |
— |
2,370 (29.4) |
||
| 75–84 |
7,654 (21.6)
|
2,329 (30.4) |
178 (2.3) |
2,054 (26.8) |
2,609 (34.1) |
484 (6.3) |
— |
2,137 (27.9) |
||
| ≥85 |
5,268 (14.9)
|
1,450 (27.5) |
105 (2.0) |
1,443 (27.4) |
1,930 (36.6) |
340 (6.5) |
— |
1,382 (26.2) |
||
|
Sex
| ||||||||||
| Male |
17,164 (48.5)
|
7,549 (44.0) |
529 (3.1) |
4,075 (23.7) |
4,308 (25.1) |
703 (4.1) |
— |
0.098 |
5,428 (31.6) |
0.087 |
| Female |
18,235 (51.5)
|
7,193 (39.4) |
707 (3.9) |
4,775 (26.2) |
4,838 (26.5) |
722 (4.0) |
— |
5,106 (28.0) |
||
|
Race or ethnicity
| ||||||||||
| White, NH |
22,967 (64.9)
|
8,837 (38.5) |
697 (3.0) |
5,843 (25.4) |
6,479 (28.2) |
1,111 (4.8) |
— |
0.285 |
6,224 (27.1) |
0.199 |
| Black, NH |
4,214 (11.9)
|
2,279 (54.1) |
212 (5.0) |
976 (23.2) |
676 (16.0) |
71 (1.7) |
— |
1,474 (35.0) |
||
| Hispanic |
3,781 (10.7)
|
1,801 (47.6) |
188 (5.0) |
960 (25.4) |
759 (20.1) |
73 (1.9) |
— |
1,491 (39.4) |
||
| Other,†† NH |
2,601 (7.3)
|
893 (34.3) |
81 (3.1) |
628 (24.1) |
880 (33.8) |
119 (4.6) |
— |
760 (29.2) |
||
| Unknown |
1,836 (5.2)
|
932 (50.8) |
58 (3.2) |
443 (24.1) |
352 (19.2) |
51 (2.8) |
— |
585 (31.9) |
||
|
Chronic respiratory condition at discharge§§
| ||||||||||
| No |
14,763 (41.7)
|
6,116 (41.4) |
555 (3.8) |
3,693 (25.0) |
3,818 (25.9) |
581 (3.9) |
— |
0.023 |
3,482 (23.6) |
0.254 |
| Yes |
20,636 (58.3)
|
8,626 (41.8) |
681 (3.3) |
5,157 (25.0) |
5,328 (25.8) |
844 (4.1) |
— |
7,052 (34.2) |
||
|
Chronic nonrespiratory condition at discharge¶¶
| ||||||||||
| No |
4,685 (13.2)
|
2,516 (53.7) |
166 (3.5) |
958 (20.4) |
949 (20.3) |
96 (2.0) |
— |
0.200 |
1,522 (32.5) |
0.050 |
| Yes |
30,714 (86.8)
|
12,226 (39.8) |
1,070 (3.5) |
7,892 (25.7) |
8,197 (26.7) |
1,329 (4.3) |
— |
9,012 (29.3) |
||
|
Omicron BA.2/BA.2.12.1–predominant period§
| ||||||||||
|
All hospitalizations
|
23,383 (100.0)
|
6,682 (28.6) |
343 (1.5) |
5,118 (21.9) |
2,350 (10.1) |
7,686 (32.9) |
1,204 (5.1) |
— |
1,564 (6.7) |
— |
|
Site
| ||||||||||
| Baylor Scott & White Health |
4,686 (20.0)
|
2,128 (45.4) |
55 (1.2) |
1,417 (30.2) |
227 (4.8) |
813 (17.3) |
46 (1.0) |
0.945 |
196 (4.2) |
0.268 |
| Columbia University |
1,413 (6.0)
|
491 (34.7) |
48 (3.4) |
316 (22.4) |
169 (12.0) |
375 (26.5) |
14 (1.0) |
81 (5.7) |
||
| HealthPartners |
1,758 (7.5)
|
329 (18.7) |
37 (2.1) |
261 (14.8) |
204 (11.6) |
760 (43.2) |
167 (9.5) |
120 (6.8) |
||
| Intermountain Healthcare |
2,023 (8.7)
|
571 (28.2) |
35 (1.7) |
446 (22.0) |
179 (8.8) |
733 (36.2) |
59 (2.9) |
167 (8.3) |
||
| KPNC |
6,866 (29.4)
|
677 (9.9) |
87 (1.3) |
1,164 (17.0) |
1,095 (15.9) |
3,105 (45.2) |
738 (10.7) |
584 (8.5) |
||
| KPNW |
1,326 (5.7)
|
356 (26.8) |
17 (1.3) |
210 (15.8) |
165 (12.4) |
488 (36.8) |
90 (6.8) |
86 (6.5) |
||
| PHIX |
12 (0.1)
|
7 (58.3) |
0 (0.0) |
3 (25.0) |
0 (0.0) |
2 (16.7) |
0 (0.0) |
1 (8.3) |
||
| Regenstrief Institute |
3,947 (16.9)
|
1,600 (40.5) |
48 (1.2) |
869 (22.0) |
246 (6.2) |
1,128 (28.6) |
56 (1.4) |
235 (6.0) |
||
| University of Colorado |
1,352 (5.8)
|
523 (38.7) |
16 (1.2) |
432 (32.0) |
65 (4.8) |
282 (20.9) |
34 (2.5) |
94 (7.0) |
||
|
Age group, yrs
| ||||||||||
| 18–49 |
4,162 (17.8)
|
2,087 (50.1) |
130 (3.1) |
979 (23.5) |
393 (9.4) |
573 (13.8) |
0 (0.0) |
0.585 |
199 (4.8) |
0.340 |
| 50–65 |
4,613 (19.7)
|
1,621 (35.1) |
78 (1.7) |
1,171 (25.4) |
527 (11.4) |
1,077 (23.3) |
139 (3.0) |
220 (4.8) |
||
| 65–74 |
5,171 (22.1)
|
1,258 (24.3) |
63 (1.2) |
1,098 (21.2) |
506 (9.8) |
1,929 (37.3) |
317 (6.1) |
277 (5.4) |
||
| 75–84 |
5,539 (23.7)
|
1,059 (19.1) |
34 (0.6) |
1,114 (20.1) |
520 (9.4) |
2,379 (42.9) |
433 (7.8) |
468 (8.4) |
||
| ≥85 |
3,898 (16.7)
|
657 (16.9) |
38 (1.0) |
756 (19.4) |
404 (10.4) |
1,728 (44.3) |
315 (8.1) |
400 (10.3) |
||
|
Sex
| ||||||||||
| Male |
10,979 (47.0)
|
3,304 (30.1) |
149 (1.4) |
2,315 (21.1) |
1044 (9.5) |
3,553 (32.4) |
614 (5.6) |
0.080 |
796 (7.3) |
0.085 |
| Female |
12,404 (53.0)
|
3,378 (27.2) |
194 (1.6) |
2,803 (22.6) |
1306 (10.5) |
4,133 (33.3) |
590 (4.8) |
768 (6.2) |
||
|
Race or ethnicity
| ||||||||||
| White, NH |
14,772 (63.2)
|
3,817 (25.8) |
162 (1.1) |
3,236 (21.9) |
1,367 (9.3) |
5,304 (35.9) |
886 (6.0) |
0.362 |
1,076 (7.3) |
0.199 |
| Black, NH |
2,690 (11.5)
|
1,157 (43.0) |
73 (2.7) |
598 (22.2) |
266 (9.9) |
525 (19.5) |
71 (2.6) |
117 (4.3) |
||
| Hispanic |
2,708 (11.6)
|
815 (30.1) |
57 (2.1) |
648 (23.9) |
353 (13.0) |
736 (27.2) |
99 (3.7) |
139 (5.1) |
||
| Other,†† NH |
2,115 (9.0)
|
425 (20.1) |
40 (1.9) |
376 (17.8) |
298 (14.1) |
842 (39.8) |
134 (6.3) |
172 (8.1) |
||
| Unknown |
1,098 (4.7)
|
468 (42.6) |
11 (1.0) |
260 (23.7) |
66 (6.0) |
279 (25.4) |
14 (1.3) |
60 (5.5) |
||
|
Chronic respiratory condition at discharge§§
| ||||||||||
| No |
10,015 (42.8)
|
3,085 (30.8) |
147 (1.5) |
2,179 (21.8) |
980 (9.8) |
3,142 (31.4) |
482 (4.8) |
0.092 |
604 (6.0) |
0.092 |
| Yes |
13,368 (57.2)
|
3,597 (26.9) |
196 (1.5) |
2,939 (22.0) |
1,370 (10.2) |
4,544 (34.0) |
722 (5.4) |
960 (7.2) |
||
|
Chronic nonrespiratory condition at discharge¶¶
| ||||||||||
| No |
3,010 (12.9)
|
1,243 (41.3) |
53 (1.8) |
690 (22.9) |
226 (7.5) |
748 (24.9) |
50 (1.7) |
0.242 | 174 (5.8) |
0.058 |
| Yes | 20,373 (87.1) | 5,439 (26.7) | 290 (1.4) | 4,428 (21.7) | 2,124 (10.4) | 6,938 (34.1) | 1154 (5.7) | 1,390 (6.8) | ||
Abbreviations: ICD-9 = International Classification of Diseases, Ninth Revision; ICD-10 = International Classification of Diseases, Tenth Revision; KPNC = Kaiser Permanente of Northern California; KPNW = Kaiser Permanente Northwest; N/A = not applicable; NH = non-Hispanic; PHIX = Paso del Norte Health Information Exchange; RT-PCR = reverse transcription–polymerase chain reaction; SMD = standardized mean or proportion difference.
* Hospitalizations with a discharge code consistent with COVID-19–like illness were included. COVID-19–like illness diagnoses included acute respiratory illness (e.g., respiratory failure or pneumonia) or related signs or symptoms (e.g., cough, fever, dyspnea, vomiting, or diarrhea) using diagnosis ICD-9 and ICD-10 codes. Clinician-ordered molecular assays (e.g., real-time RT-PCR) for SARS-CoV-2 occurring ≤14 days before to <72 hours after the encounter date were included.
† Partners contributing data on hospitalizations during dates of estimated ≥75% Omicron BA.1 predominance were in California (Dec 21, 2021–Mar 6, 2022), Colorado (Dec 25, 2021–Mar 12, 2022), Indiana (Dec 31, 2021–Mar 4, 2022), Minnesota and Wisconsin (Jan 1–Mar 5, 2022), New York (Dec 18, 2021–Feb 26, 2022), Oregon and Washington (Jan 1–Mar 12, 2022), Texas (Baylor Scott & White Health [Dec 18, 2021–Mar 5, 2022] and PHIX [Jan 8–Mar 19, 2022]), and Utah (Dec 27, 2021–Mar 19, 2022).
§ Partners contributing data on hospitalizations during dates of estimated ≥75% Omicron BA.2/BA.2.12.1 predominance were in California (Mar 25–Jun 10, 2022), Colorado (Apr 9–Jun 4, 2022), Indiana (Mar 19–Jun 10, 2022), Minnesota and Wisconsin (Apr 9–Jun 4, 2022), New York (Mar 26–Jun 10, 2022), Oregon and Washington (Apr 9–Jun 10, 2022), Texas (Baylor Scott & White Health [Mar 26–Jun 4, 2022] and PHIX [Apr 23–Jun 10, 2022]), and Utah (Mar 28–Jun 10, 2022).
¶ Vaccination was defined as having received the listed number of doses of an mRNA-based COVID-19 vaccine within the specified range of number of days before the hospitalization 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 hospitalization or the admission date if testing only occurred after the admission.
** An absolute SMD ≥0.20 indicates a nonnegligible difference in variable distributions between hospitalizations for vaccinated versus unvaccinated patients or for patients with SARS-CoV-2–positive results versus those with SARS-CoV-2–negative results. For mRNA COVID-19 vaccination status, a single SMD was calculated by averaging the absolute SMDs obtained from pairwise comparisons of each vaccinated category versus unvaccinated; more specifically, as the average of the absolute value of the SMDs for 1) vaccinated with 2 doses 14–149 days earlier versus unvaccinated, 2) vaccinated with 2 doses ≥150 days earlier versus unvaccinated, 3) vaccinated with 3 doses 7–119 days earlier versus unvaccinated, 4) vaccinated with 3 doses ≥120 days earlier versus unvaccinated, and 5) vaccinated with 4 doses ≥7 days earlier versus unvaccinated.
†† Other race includes Asian, Native Hawaiian or other Pacific islander, American Indian or Alaska Native, Other, 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 ICD-9 and ICD-10 diagnosis codes.
¶¶ 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 ICD-9 and ICD-10 diagnosis.