Table 3.
COVID-19–Related Hospitalization/Death Rates per 10,000 Patient-Days and Vaccine Effectiveness From February 1 Through December 18, 2021
| N | Days at Risk |
Events ≤30 d From COVID-19 Diagnoses |
OR (95% CI) |
Vaccine Effectiveness | ||||
|---|---|---|---|---|---|---|---|---|
| Total | Median [IQR] | No. | Rate per 10,000 d | Unadjusted | Adjusted | |||
| February 1 to December 18, 2021 | ||||||||
| Unvaccinated | 14,806 | 1,404,729 | 54 [30-98] | 200 | 1.45 | 1.00 (reference) | 1.00 (reference) | – |
| Partially vaccinated | 12,433 | 396,399 | 28 [21-28] | 41 | 1.03 | 0.70 (0.50-0.98) | 0.67 (0.47-0.95) | 33%a |
| Fully vaccinated | 12,403 | 2,346,397 | 207 [153-242] | 183 | 0.78 | 0.51 (0.41-0.63) | 0.47 (0.38-0.58) | 53% |
| BNT162b2 | 5,132 | 933,674 | 198 [142-234] | 91 | 0.97 | 0.67 (0.52-0.86) | 0.61 (0.47-0.79) | 39% |
| mRNA-1273 | 6,853 | 1,339,710 | 214 [161-245] | 79 | 0.59 | 0.40 (0.31-0.52) | 0.37 (0.28-0.49) | 63% |
| Ad26.COV2.S | 368 | 67,853 | 240 [123-250] | 13 | 1.92 | 1.35 (0.76-2.39) | – | – |
| February 1 to June 19, 2021 (pre–Delta variant period) | ||||||||
| Unvaccinated | 12,055 | 737,051 | 52 [27-79] | 62 | 0.84 | 1.00 (reference) | 1.00 (reference) | – |
| Partially vaccinated | 10,101 | 272,714 | 28 [21-28] | 20 | 0.73 | 0.87 (0.52-1.44) | 0.89 (0.52-1.50) | NA |
| Fully vaccinated | 10,031 | 715,583 | 69 [51-94] | 11 | 0.15 | 0.17 (0.09-0.33) | 0.16 (0.08-0.34) | 84% |
| BNT162b2 | 3,987 | 286,045 | 69 [40-101] | 6 | 0.21 | 0.25 (0.11-0.57) | 0.22 (0.09-0.55) | 78% |
| mRNA-1273 | 5,750 | 411,078 | 72 [54-88] | 4 | 0.10 | 0.11 (0.04-0.32) | 0.13 (0.05-0.35) | 87% |
| Ad26.COV2.S | 278 | 17,478 | 62 [59-76] | 1 | 0.57 | 0.68 (0.09-4.91) | – | – |
| June 20 to December 18, 2021 (Delta variant period) | ||||||||
| Unvaccinated | 3,265 | 402,236 | 182 [57-182] | 123 | 3.06 | 1.00 (reference) | 1.00 (reference) | – |
| Partially vaccinated | 1,440 | 68,762 | 28 [21-50] | 18 | 2.62 | 0.84 (0.51-1.38) | 0.80 (0.48-1.34) | NA |
| Fully vaccinated | 11,647 | 1,534,287 | 143 [99-182] | 171 | 1.11 | 0.34 (0.27-0.43) | 0.30 (0.23-0.38) | 70% |
| BNT162b2 | 4,814 | 604,472 | 124 [96-182] | 84 | 1.39 | 0.44 (0.33-0.58) | 0.39 (0.29-0.53) | 61% |
| mRNA-1273 | 6,458 | 878,136 | 151 [101-182] | 75 | 0.85 | 0.27 (0.20-0.36) | 0.23 (0.17-0.32) | 77% |
| Ad26.COV2.S | 335 | 48,205 | 182 [114-182] | 12 | 2.49 | 0.81 (0.44-1.48) | – | – |
Although patients can contribute time to any vaccination status, the N in the first column (no. of individuals contributing to time at risk) refers to patients’ status at the end of follow-up. “Unvaccinated” includes patients who never received a vaccine and those who received a single dose of a vaccine ≤14 days earlier; “partially vaccinated” includes patients who received the first mRNA vaccine dose ≥14 days earlier after but the second dose <14 days earlier; “fully vaccinated” includes all patients who received the last vaccine dose ≥14 days earlier. Median days at risk included time to event (ie, infection) or time to censoring point for non-event cases (eg, end of study, non-COVID-19–related death, transplantation, loss-of-follow-up, received another SARS-CoV-2 vaccination). The median time was calculated for all patients. Multivariable logistic model was used to derive odds ratio, adjusted for age, sex, race, diabetes, dialysis modality, congregate living status, dialysis adequacy, albumin, hepatitis B virus seroimmunity, disability, comorbidity, number of and specific comorbidities (diabetes, chronic obstructive pulmonary disease, chronic heart failure, hypertension, peripheral vascular disease, cancer, alcohol or drug abuse), immunocompromised status, and 75th percentile of county SARS-CoV-2 infection rate to account for geotemporal variability in the intensity of the epidemic. Abbreviations: mRNA, messenger RNA; NA, not applicable; OR, odds ratio.
Patient hospitalized for COVID-19 before receipt of second mRNA vaccine.