Moderna vaccine no match for omicron except with booster, study finds : Shots - Health News The Moderna vaccine's ability to shield against infection drops sharply when tested on the omicron variant. But getting a booster pumps the protection back up again, new research suggests.

Omicron evades Moderna vaccine too, study suggests, but boosters help

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There's more mixed news today about the power of the vaccines to protect people against the omicron variant, this time from the Moderna vaccine. NPR health correspondent Rob Stein joins us now with details. And, Rob, I know there's been reporting about the Pfizer vaccine and how it protects against the omicron variant. We have not heard as much about Moderna. Tell us the difference. What have you learned?

ROB STEIN, BYLINE: Yeah, yeah. That's right. So the new evidence today comes from researchers at the National Institutes of Health and Duke University. These teams tested antibodies from the blood of 30 people who got two Moderna shots and 17 people who also got a booster, a Moderna booster. And first, the bad news - antibodies from the first two shots appear to be far less effective at neutralizing the omicron variant in the lab. Here's David Montefiori at Duke. He helped conduct the experiment.

DAVID MONTEFIORI: The antibodies that people make after they get the standard two inoculations of the Moderna vaccine are 50 times less effective against omicron than they are against the original form of the virus, which is an indication that there's going to be a greater risk of breakthrough infections with omicron.

STEIN: And that's obviously disappointing, you know, because Moderna's protection had seemed like it might be a bit stronger than the other vaccines, raising some hope that it would be better against omicron, too. But it looks like it's about the same as the Pfizer vaccine when it comes to omicron.

CORNISH: You also said they tested people who got a Moderna booster. What did they find about that?

STEIN: Yeah, so that's the good news. Just like Pfizer, this experiment indicates that getting a Moderna booster pumps the protection basically back up to where it's been against delta. Here's David Montefiori again.

MONTEFIORI: What these results are telling us is that if omicron becomes a dominant variant, it's going to become even more important that people get their boost.

STEIN: But based on these findings and similar findings about the Pfizer vaccine, it looks like a third shot of these vaccines should suffice - you know, no need for a whole new vaccine specifically targeted at omicron. Here's Dr. Anthony Fauci at today's White House briefing.


ANTHONY FAUCI: Our booster vaccine regimens work against omicron. At this point, there is no need for a variant-specific booster. And so the message remains clear; if you are unvaccinated, get vaccinated. And particularly in the arena of omicron, if you are fully vaccinated, get your booster shot.

CORNISH: What do we know so far about Johnson & Johnson?

STEIN: Yeah, yeah. So scientists are doing similar experiments testing the J&J vaccine alone, as well as the J&J vaccine with a Pfizer booster right now and expect to have some results by early next week.

CORNISH: At this point, where do things stand with omicron in this country?

STEIN: Yeah, so omicron has already been detected in at least 33 states and is spreading fast. It's already been detected in 13% of samples in the New York and New Jersey area, for example. And based on how fast omicron is spreading in other countries, it seems like omicron is on a trajectory to overtake delta and quickly become the dominant mutant in this country within weeks. So that's, you know, setting off big alarm bells, especially because delta is already surging across the country, pushing many hospitals to their limit and killing more than 1,100 people a day.

I talked with one researcher today who's advising the CDC who says in the most pessimistic scenario, things could get as bad as last winter's horrific surge. But, she stresses, there's so much uncertainty about omicron, it's really impossible to really know at this point how bad things might get.

CORNISH: That's NPR health correspondent Rob Stein. Thank you for the update.

STEIN: Sure thing.

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