Table 3.
Incidence rate, hazard ratio, and VE of 2 doses of mRNA-1273 vaccine in preventing COVID-19 infection by age, sex, race/ethnicity, history of COVID-19, and asymptomatic/symptomatic COVID-19 subgroups.
| Vaccinated (N=352878) |
Unvaccinated (N=352878) |
Hazard Ratio (95% CI) |
VE (95% CI) |
VE (98.3% CI) |
|||||
|---|---|---|---|---|---|---|---|---|---|
| Number of cases | Incidence per 1000 person-years (95% CI) |
Number of cases | Incidence per 1000 person-years (95% CI) |
Unadjusted | Adjusteda | Unadjusted | Adjusteda | Adjusteda | |
| Overall | |||||||||
| Asymptomatic | 35 | 0.34 (0.24-0.47) | 66 | 1.17 (0.92-1.48) | 0.33 (0.22-0.50) | 0.27 (0.18-0.42) | 67.2% (50.3-78.3%) | 72.7% (57.6-82.4%) | 72.7% (53.4-84.0%) |
| Symptomatic | 254 | 2.44 (2.15–2.76) | 1078 | 19.04 (17.93-20.21) | 0.13 (0.12-0.15) | 0.12 (0.10-0.13) | 86.6% (84.6-88.3%) | 88.3% (86.5-89.9%) | 88.3% (86.1-90.2%) |
| Age at index date, years | |||||||||
| 18-44 | 93 | 3.58 (2.92–4.39) | 350 | 22.71 (20.45-25.22) | 0.17 (0.13-0.21) | 0.13 (0.10-0.16) | 83.3% (78.9-86.7%) | 87.2% (83.6-90.1%) | 87.2% (82.7-90.6%) |
| 45-64 | 83 | 3.18 (2.56-3.94) | 316 | 26.43 (23.67-29.51) | 0.13 (0.10-0.16) | 0.11 (0.09-0.15) | 87.3% (83.7-90.1%) | 88.7% (85.3-91.4%) | 88.7% (84.5-91.8%) |
| 65-74 | 54 | 1.77 (1.36–2.31) | 272 | 16.59 (14.73-18.68) | 0.11 (0.08-0.15) | 0.11 (0.08-0.14) | 88.6% (84.7-91.5%) | 89.4% (85.6-92.1%) | 89.4% (84.6-92.7%) |
| ≥75 | 59 | 2.72 (2.11–3.51) | 206 | 16.02 (13.97-18.36) | 0.17 (0.13-0.23) | 0.17 (0.12-0.23) | 82.5% (76.6-86.9%) | 83.0% (76.8-87.6%) | 83.0% (75.2-88.4%) |
| Sex | |||||||||
| Female | 175 | 2.81 (2.42-3.26) | 702 | 20.84 (19.35-22.44) | 0.14 (0.12-0.17) | 0.12 (0.10-0.14) | 85.9% (83.3-88.1%) | 87.9% (85.6-89.9%) | 87.9% (85.0-90.3%) |
| Male | 114 | 2.71 (2.26–3.26) | 442 | 19.27 (17.55–21.15) | 0.15 (0.12–0.18) | 0.13 (0.11–0.17) | 85.0% (81.6–87.9%) | 86.6% (83.3–89.2%) | 86.6% (82.5–89.7%) |
| Race/Ethnicity | |||||||||
| Non–Hispanic White | 86 | 2.15 (1.74–2.66) | 399 | 17.46 (15.83–19.26) | 0.13 (0.10–0.16) | 0.11 (0.09–0.14) | 87.1% (83.7–89.8%) | 88.7% (85.5–91.1%) | 88.7% (84.7–91.6%) |
| Non–Hispanic Black | 23 | 3.04 (2.02–4.58) | 107 | 25.60 (21.19–30.94) | 0.11 (0.07–0.18) | 0.11 (0.07–0.17) | 88.6% (82.1–92.8%) | 89.2% (82.6–93.4%) | 89.2% (80.6–94.0%) |
| Hispanic | 142 | 4.24 (3.60–5.00) | 462 | 25.11 (22.92–27.51) | 0.18 (0.15–0.22) | 0.16 (0.13–0.19) | 81.7% (77.8–84.9%) | 84.4% (80.9–87.2%) | 84.4% (80.0–87.8%) |
| Non–Hispanic Asian | 22 | 1.32 (0.87–2.01) | 116 | 15.83 (13.20–18.99) | 0.10 (0.06–0.15) | 0.08 (0.05–0.13) | 90.5% (84.8–94.0%) | 91.8% (86.6–94.9%) | 91.8% (85.1–95.5%) |
| History of COVID–19 infection | |||||||||
| No | 245 | 2.51 (2.22–2.85) | 1104 | 21.66 (20.42–22.98) | 0.12 (0.11–0.14) | 0.11 (0.09–0.12) | 87.8% (85.9–89.4%) | 89.3% (87.6–90.8%) | 89.3% (87.2–91.1%) |
| Yesb | 44 | 6.50 (4.84–8.73) | 40 | 7.07 (5.19–9.64) | 0.91 (0.59–1.40) | 0.92 (0.58–1.45) | 9.1% (0.0–41.0%) | 8.2% (0.0–41.8%) | 8.2% (0.0–47.3%) |
| Yesc | 27 | 3.99 (2.73–5.81) | 31 | 5.48 (3.85–7.79) | 0.69 (0.41–1.16) | 0.66 (0.38–1.15) | 31.1% (0.0–59.0%) | 33.6% (0.0–61.5%) | 33.6% (0.0–65.8%) |
Adjusted for covariates: age (not adjusted in the age subcohort analysis), sex (not adjusted in the sex subcohort analysis), race/ethnicity (not adjusted in the race/ethnicity subcohort analysis), frailty index (in quartiles), history of COVID-19 infection (not adjusted in the history of COVID-19 infection subcohort analysis), history of SARS-CoV-2 molecular test, number of outpatient and virtual visits, preventive care, Medicaid, neighborhood median household income, KPSC physician/employee status, medical center area.
Cases in this category were defined as having a COVID-19 diagnosis code with chart-confirmed symptoms or a SARS-CoV-2 positive molecular test, with no history of a COVID-19 diagnosis code or SARS-CoV-2 positive molecular test in the 90 days prior.
Cases in this category were defined as having a COVID-19 diagnosis code with chart-confirmed symptoms, a SARS-CoV-2 positive molecular test with chart-confirmed symptoms, or a SARS-CoV-2 positive molecular test with an intervening SARS-CoV-2 negative molecular test; cases also had no history of a COVID-19 diagnosis code or SARS-CoV-2 positive molecular test in the 90 days prior.