What is vaccine efficacy, and will the current vaccines protect us from new strains of Covid-19?

Updated Jan. 6, 2022 

Vaccine efficacy is how well the vaccine works to prevent the disease for which it is designed. Covid-19 vaccines are effective against severe disease and death from variants of the virus that causes Covid-19 currently circulating in the United States. When these infections occur among vaccinated people, they tend to be mild. 

The CDC continues to monitor the spread of identified variants, characterize emerging viral variants, and expand its ability to find new SARS-CoV-2 variants.