Vaccine Effectiveness

COVID-19 Vaccine Safety Effectiveness Overview - Vaccine Fast Details Matrix

Vaccine Fast Details Matrix

Protection Against Any Symptoms Protection Against Severe Symptoms Protection Against Hospitalization or Death Ages
Phizer-BioNTech mRNA 2 95% 89% 100% Ages 16 to 55: 96% efficacy
Over age 55: 94% efficacy
FDA letter of EUA for Pfizer
Moderna mRNA 2 94.1% 100% 100% Ages 18 to 65: 96% efficacy
Over age 65: 86% efficacy
FDA letter of EUA for Moderna
Johnson & Johnson Viral vector adenovirus (cold virus) 1 66% (U.S. 72%) 85% 100% Ages 18 to 64: 66.1% effective
Over age 65: 66.2% effective
FDA letter of EUA for Johnson & Johnson

* Effectiveness is measured as the case rate of the placebo group minus the case rate of the vaccine group divided by the case rate of the placebo group. The difference between the efficacy of Pfizer and Moderna vaccines in older adults may be due to the cut-off age for the trial. For example, it is possible that the Pfizer vaccine would have a lower protection effect had they reported data for those over age 65. The Johnson & Johnson vaccine was tested in different countries. U.S., Brazil, and South Africa, some of which had greater prevalence of mutated strains of the Coronavirus, for which the vaccine was less effective. The results are for pooled samples from all three countries.

More information available on the OC Health Care Agency website:

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