According To The CDC, Which COVID-19 Vaccine Is The Most Effective?

In the United States, you have three COVID-19 vaccines available to you: Pfizer, Moderna, and Johnson & Johnson. The Centers for Disease Control and Prevention led a nationwide study on these three vaccines' effectiveness at preventing COVID-19 hospitalizations from March 11 to August 15, 2021.

They found that vaccines do vary in effectiveness, but they all provide substantial protection from severe COVID-19. Despite both being mRNA vaccines, there is a notable difference between the Pfizer and Moderna vaccines' effectiveness. These "differences in VE [vaccine effectiveness]" may come down to the amount of mRNA content in each vaccine, the "timing between doses," or "possible differences between groups that received each vaccine that were not accounted for in the analysis," the CDC revealed.

While both Moderna and Pfizer vaccines use genetic material known as messenger RNA (mRNA) to provide immunity, the Johnson & Johnson vaccine uses a viral vector, an inactive adenovirus — that is, a common cold virus.

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."