The Centers for Disease Control and Prevention worked with researchers nationwide to study 3,689 adults “without immunocompromising conditions” at 21 hospitals across 18 states for nearly five months. They also looked at the antibodies in the blood of 100 healthy volunteers two to six weeks after they were fully vaccinated with one of the three vaccines.
The CDC released its results on September 17, 2021, revealing that the Moderna COVID-19 vaccine is the most effective, with Pfizer coming in second and Johnson & Johnson coming in last. As far as preventing hospitalizations due to COVID-19, Moderna was found to be 93% effective, Pfizer was 88% effective, and Johnson & Johnson was 71% effective.
The CDC revealed, “Although these real-world data suggest some variation in levels of protection by vaccine, all FDA-approved or authorized COVID-19 vaccines provide substantial protection against COVID-19 hospitalization.”