LEILA FADEL, HOST:
President Biden has an extra COVID shot. He rolled up his sleeve yesterday for the latest booster.
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PRESIDENT JOE BIDEN: Now is the time to do it - by Halloween, if you can. That's the best time. And that way you can be protected for the holidays.
FADEL: Some research questions, though, whether the new bivalent boosters that target omicron are any better than the old shots.
STEVE INSKEEP, HOST:
Researchers at Columbia and Harvard University studied that. Here's Dr. David Ho at Columbia.
DAVID HO: To our disappointment, the bivalent vaccine did not show superiority over the original vaccine.
INSKEEP: His team found that about a month after getting the shot, people did not have significantly higher levels of antibodies to neutralize the dominant omicron subvariants.
FADEL: But Deepta Bhattacharya at the University of Arizona considers the new studies too small and too short for firm conclusions.
DEEPTA BHATTACHARYA: For those who are saying see, see, I told you so, I would say, let's stand down a little bit and wait for some cleaner data to come out because these studies can't be used to support really one argument or another.
INSKEEP: Dr. John Wherry at the University of Pennsylvania is also saying to wait.
JOHN WHERRY: It's a little bit of a - sort of a reality check or a reset that the bivalent vaccines are not a magic bullet. They're not going to give us, you know, perfect protection from these new omicron variants that are circulating.
FADEL: Only about 20 million people have stepped up to receive a new booster, even though more than 10 times that number - over 200 million people - have been eligible since Labor Day.
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