Who Will Qualify for a Third Dose?
The CDC recommendation applies to people who are moderately or severely immunocompromised.
The CDC estimates that 2.7% U.S. adults, or about 7 million people, are immunocompromised.

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These individuals may receive a third shot 28 or more days after completing the two-dose mRNA series.
People should make a run at get an additional dose that matches their earlier doses.
If unavailable, mixing the mRNA vaccines is okay for those 18 and older, the panel said.
Children and teens 5-17 years old can only receive the Pfizer vaccine at this time.
The FDAsaidit is working to ensure that immunocompromised people vaccinated with the Johnson & Johnson vaccine become optimally protected.
The CDC is not recommending antibody tests before or after additional shots.
Currently, there are no FDA-approved antibody tests to accurately measure post-vaccine immunity.
Like the earlier shots, third doses will be free and administered at pharmacies and other health-care sites.
The FDA has now authorized a booster dose for all individuals 12 years and older in the U.S. For the most recent updates on COVID-19, visit ourcoronavirus news page.
Centers for Disease Control and Prevention.COVID-19 vaccine booster shots.