TABLE 2. Adjusted effectiveness* of full vaccination† with mRNA COVID-19 vaccines against COVID-19–associated hospitalization among veterans, by characteristics of case-patients and controls — five Veterans Affairs Medical Centers,§ United States, February 1–August 6, 2021.
| Characteristic | n/N (%) |
Adjusted vaccine effectiveness % (95% CI) | |
|---|---|---|---|
| Case-patients vaccinated/total | Controls vaccinated/total | ||
|
Overall
|
54/388 (13.9)
|
378/787 (48.0)
|
86.8 (80.4–91.1)
|
|
Age group, yrs
| |||
| 18–64 |
10/199 (5.0) |
93/275 (33.8) |
95.1 (89.1–97.8) |
| ≥65 |
44/189 (23.3) |
285/512 (55.7) |
79.8 (67.7–87.4) |
|
Race/Ethnicity¶
| |||
| Black, non-Hispanic |
24/195 (12.3) |
169/379 (44.6) |
86.9 (76.9–92.6) |
| White, non-Hispanic |
21/141 (14.9) |
171/334 (51.2) |
88.1 (77.4–93.8) |
|
COVID-19 vaccine product among fully vaccinated
| |||
| BNT162b2 (Pfizer-BioNTech) |
43/388 (11.1) |
242/787 (30.7) |
83.4 (74.0–89.4) |
| mRNA-1273 (Moderna) |
11/388 (2.8) |
136/787 (17.3) |
91.6 (83.5–95.7) |
|
Date of hospital admission
| |||
| February 1–June 30 |
22/270 (8.1) |
249/618 (40.3) |
84.1 (74.1–90.2) |
| July 1–August 6 |
32/118 (27.1) |
129/169 (76.3) |
89.3 (80.1–94.3) |
|
No. of days since fully vaccinated
| |||
| <90 days |
19/388 (4.9) |
215/787 (27.3) |
86.1 (76.5–91.8) |
| ≥90 days | 35/388 (9.0) | 163/787 (20.7) | 87.2 (78.2–92.5) |
Abbreviation: CI = confidence interval.
*All nonstratified models adjusted for study site, time (admission date), age, sex, and race/ethnicity. Stratified models exclude adjustment for stratification variable.
† Full vaccination was defined as receipt of both doses of an mRNA COVID-19 vaccine (Pfizer-BioNTech or Moderna) ≥14 days before the first SARS-CoV-2 test performed within 14 days before admission or during the first 72 hours of hospitalization.
§ Atlanta, Georgia; Bronx, New York; Houston, Texas; Los Angeles, California; and Palo Alto, California.
¶ Because of small numbers of veterans in other racial/ethnic groups, vaccine effectiveness was estimated only for non-Hispanic Black and non-Hispanic White persons.