Explainer-Updated COVID vaccines are coming to U.S. Should you get one?

[September 03, 2022] 

By Julie Steenhuysen

CHICAGO(Reuters) -Updated COVID-19 booster shots for people aged 12 years and above to target the BA.4 and BA.5 Omicron subvariants of the coronavirus are on the way after receiving the go-ahead from U.S. regulators.

The green light for the use of Omicron COVID boosters from Pfizer Inc with German partner BioNTech SE and Moderna Inc will enable millions of the retooled shots to roll out by the end of the weekend.

Here is what you need to know:

WHO SHOULD GET AN UPDATED BOOSTER?

All people age 12 and older who have received the original two-dose vaccine are eligible. The Pfizer vaccine is authorized for people 12 and older, while Moderna's is for those 18 and above.

Government health officials say the boosters are needed because immunity wanes over time and the vaccines help prevent serious disease and death. They also say younger people can benefit as the new shots could help prevent long COVID, which can involve a wide array of debilitating symptoms than can linger for months.

Several experts said they do not expect the updated vaccines to be game changing and urged public health officials not to overstate their benefits.

WHAT IF I RECENTLY HAD A BOOSTER OR COVID?

The U.S. Food and Drug Administration said people must wait at least two months after a booster shot to get an updated vaccine, and the expert vaccine committee for the U.S. Centers for Disease Control and Prevention backed that view.

People who have had COVID may consider waiting three months before seeking a booster, CDC officials said this week.

Experts were surprised by the two-month recommendation.

John Moore, a professor of microbiology and immunology at Weill Cornell Medical College in New York, said waiting at least four months, and possibly even six, may result in a better immune response.

Moore said a booster shot restores antibody levels to where they were after a person's most recent encounter with the virus, either via vaccine or infection.

If antibody levels are relatively high when a person gets another booster, they could even interfere with the effect of the booster, he said.

WHAT DOES THE DATA SAY?

The FDA relied on data from human trials of vaccines that incorporated the first version of the coronavirus as well as prior variants, including the BA.1 Omicron variant that was dominant this past winter.

Pfizer and Moderna also presented data on the BA.4/BA.5 boosters from studies in labs and animals.

Because the vaccine is better matched to the BA.5 subvariant of the virus that is still widely circulating, it could be more successful at preventing infections than the ones just targeting the original virus.

Eric Topol, a genomics expert and director of the Scripps Research Translational Institute in La Jolla, California, said that is what is wished for, but it may not happen.

He said the updated shots will likely be effective against BA.4.6, a newer subvariant of Omicron that is on the rise in the United States.

(Additional reporting by Ahmed Aboulenein in Washington and Mrinalika Roy in Bengaluru; Editing by Caroline Humer, Bill Berkrot and Shinjini Ganguli)

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