"Individuals who are 50 years or older, or certain immune-compromised individuals can get a second booster," said Dr. Sofe Mekuria of Contra Costa Health Services.
With it now authorized by both the CDC and the FDA, some Bay Area counties started giving out second booster shots on Wednesday.
In Contra Costa County, Doctor Mekuria says, the demand on the first day was strong.
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"I do know we have been seeing, most people coming in today, have been requesting boosters," she said.
But despite the federal authorization that came down on Tuesday, some experts say they don't think everyone will need to get a second booster.
They point to the fact that in early studies, data doesn't necessarily show a large benefit for people who are not elderly nor immuno-compromised.
"They actually had no increased effectiveness of getting a fourth shot over a third shot of reinfection. Nor did that bring down their viral loads," said infectious disease expert, Dr. Monica Gandhi.
She says the US is an outlier among other developed countries in Europe and Canada in recommending the shot for healthy individuals as young as 50.
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"I think there is a problem here where we think that we can stop all infection with booster shots. And I think this could be an American fallacy because the other countries are really protecting against severe disease," Dr. Gandhi said.
And while all the doctors told ABC7 News getting a second booster was not a bad idea, they said a fourth shot isn't as imperative as getting the first three.
"If I had to say one thing which will give the biggest benefit, for all of those people who haven't gotten their third shot yet, please get it," said infectious disease specialist, Dr. Peter Chin-Hong.
Next week, the FDA will consider a second booster shot for all Americans, as well as a variant-specific booster.
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