SAN DIEGO COUNTY, Calif. — Pfizer has asked the FDA to authorize a fourth COVID-19 vaccine shot for those 65 and older.
Experts say eventually we'll all need another booster, but at this point it's only recommended for those who are immunocompromised.
"It is necessary for a 4th booster," said Pfizer CEO, Dr. Albert Bourla, during an appearance on CBS Mornings.
He said a second booster shot is necessary for protection against COVID-19.
"The protection they're getting from the third, it is good enough. Actually quite good against hospitalizations and deaths, but it doesn’t last very long," said Dr. Bourla.
On Tuesday, Pfizer asked the FDA to authorize an additional booster dose of their vaccine to people 65 and older.
They submitted data, which showed people in a research group 60 and over who got a fourth dose were, half as likely to become infected and four-times less likely to fall severely ill than those who had only three shots.
Right now in the United States, the CDC has only said a fourth shot is needed for those who are immunocompromised or have specific health issues.
"Those are the people I'd put at the front of the line to get those boosters," said Dr. Davey Smith, the head of the Division of Infectious Diseases and Global Public Health at UC San Diego.
CBS 8 asked Dr. Smith to address some of the common booster related questions you might have, including why they're needed in the first place.
"We just have to keep reminding our immune system to fight off the virus and that means more boosters," said Dr. Smith.
What about mixing brands?
If someone already has a Pfizer booster, can they get a Moderna?
"The research hasn't finished, but the little data we so have looks like it's ok for people to mix and match," said Dr. Smith.
Dr. Smith says though they’re being worked on, there are no variant specific boosters, but research shows the vaccine we all started off with does offer protection against new variants.
"It might mean people can still contract the virus, but they don't get sick and that's the most important part, they don't get sick enough where they need to go to the hospital or die, but it does mean they could contract the virus if they get exposed," said Dr. Smith.
It's unclear when the FDA will authorize a 4th dose for the general population.
Experts believe that could happen by the fall of this year.
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