Peer-reviewed data show high protection for leading COVID vaccines | CIDRAP.

What is the difference between Pfizer and Moderna vaccine?

Moderna's shot contains 100 micrograms of vaccine, more than three times the 30 micrograms in the Pfizer shot. And Pfizer's two doses are given three weeks apart, while Moderna's two-shot regimen is administered with a four-week gap.

Is the Pfizer COVID-19 booster safe?

In a study of a several hundred people who received a booster dose, researchers from Pfizer-BioNTech reported that the additional dose is safe and can raise antibody levels back up to those achieved immediately after the second dose, particularly among people over age 65 years.