covid-19 coronavirus booster vaccination needle

The Centers for Disease Control and Prevention does not recommend more than one updated COVID-19 booster shot at this time for adults who have completed their primary series of vaccinations, according to guidance information updated this week.

The Food and Drug Administration in August authorized omicron-targeting vaccines made by Pfizer-BioNTech and Moderna as preferred COVID booster shots. Unlike the original monovalent vaccines, these vaccines are bivalent, protecting against both the original virus that causes COVID-19 and omicron variants BA.4 and BA.5.

In February, the CDC’s independent vaccine advisers decided that current evidence did not support more than one yearly dose of the newer, bivalent vaccines, including for older adults and other groups vulnerable to severe disease. That decision was largely based on a lack of existing data on the efficacy of multiple doses. But the CDC itself did not confirm a stance on the issue at the time.

The new CDC guidance appears a FAQ webpage directed at the public, as reported by the San Francisco Chronicle Tuesday. The CDC answers the hypothetical question of whether one should receive more than a single, updated booster by stating, “No. Currently, CDC recommends one updated COVID-19 booster dose” for everyone aged 5 years and older, and for certain younger children.

“If you have completed your updated booster dose, you are currently up to date. There is not a recommendation to get another updated booster dose,” it added in another post update March 2. In addition, the Food and Drug Administration has not authorized more than one shot.

Health officials appear to be leaning toward an emphasis on preventing severe disease as a priority over preventing infections, the Chronicle noted.

“The bottom line is that there is some waning of protection for those who got boosters more than six months ago and haven’t had an intervening infection,” Bob Wachter, MD,  chair of medicine at the University of California, San Francisco, told the news outlet. “[T]he level of protection versus severe infection continues to be fairly high, good enough that people who aren’t at super high risk are probably fine waiting until a new booster comes out in the fall.”

Clinically fragile adults, such as some elderly adults and many nursing home residents remain high risk of severe outcomes from COVID-19.  

In the meantime, the World Health Organization’s vaccination advisory group also has adjusted its COVID-19 vaccination guidance. It now recommends that countries prioritize at-risk older adults and frontline healthcare workers, among other high-risk groups — for both initial shots and boosters. With immunity levels high from infections and vaccinations, there is no longer an urgent need to prioritize healthy younger adults and children for the shots, it announced Tuesday.

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FDA authorizes omicron-targeting vaccines as preferred COVID booster shots