A Guide to Moderna’s COVID-19 Vaccine

Moderna’s mRNA vaccine is the second COVID-19 vaccine authorized for use in the U.S. Here, we give a rundown of basic facts about the vaccine and an overview of how it works.

Quick Summary
Vaccine name: mRNA-1273

Design type: mRNA

Dose number: 2 doses, 28 days apart

Efficacy: 94.1% efficacy in preventing symptomatic COVID-19 in adults two weeks or more after receipt of the second dose.

Safety: No serious safety concerns reported. The shots, however, commonly elicit reactions in people that can include injection site pain, fatigue, headache, muscle...