Table 5.
Incidence rates of ICU admission within 21 days of SARS-CoV-2 PCR test in vaccinated and 1-to-1 propensity-matched unvaccinated cohorts and corresponding vaccine effectiveness against COVID-19-related ICU admission
| Vaccine | Time period | Vaccinated incidence rate: Cases/person-days [per 1,000 person-days] (no. of individuals contributing) | Unvaccinated incidence rate cases/person-days [per 1,000 person-days] (no. of individuals contributing) | Incidence rate ratio (95% CI) | Vaccine effectiveness (95% CI) |
|---|---|---|---|---|---|
| BNT162b2 | on or after 7 days following the second dose | 0/1,915,733. [0] (n = 35,990) | 9/1,838,072. [0.0049] (n = 35,011) | 0 (0, 0.49) | 100.0% (51.4%, 100%) |
| on or after 14 days following the second dose | 0/1,671,730. [0] (n = 33,963) | 6/1,599,732. [0.0038] (n = 32,910) | 0 (0, 0.81) | 100.0% (18.7%, 100%) | |
| mRNA-1273 | on or after 7 days following the second dose | 0/495,630. [0] (n = 11,612) | 8/479,979. [0.017] (n = 11,332) | 0 (0, 0.57) | 100% (43.3%, 100%) |
| on or after 14 days following the second dose | 0/417,743. [0] (n = 10,610) | 6/403,589. [0.015] (n = 10,318) | 0 (0, 0.82) | 100% (17.9%, 100%) |
Incidence rate is calculated as the number of individuals who were admitted to the ICU within 21 days of their first positive PCR test per 1,000 person-days. Time period: time period relative to the first vaccine dose for the vaccinated cohort or study enrollment day for the unvaccinated cohort. Vaccinated incidence rate: number of individuals experiencing the outcome in the vaccinated cohort in the time period, divided by the number of at-risk person-days for the vaccinated cohort in the time period; in brackets, the number of cases per 1,000 person-days. Unvaccinated incidence rate: number of individuals experiencing the outcome in the propensity-matched unvaccinated cohort in the time period, divided by the number of at-risk person-days for the propensity-matched unvaccinated cohort in the time period; in brackets, the number of cases per 1,000 person-days. Incidence rate ratio: vaccinated incidence rate divided by unvaccinated incidence rate along with the exact 95% CI.16 Vaccine effectiveness: 100% × (1 − incidence rate ratio) along with the 95% CI.