Finally, we have a booster to fight the specific coronavirus variant that is infecting America, BA.5, which accounts for about 90 percent of cases nationally.
On Wednesday, the United States Food and Drug Administration (FDA) authorized both the Moderna’s and Pfizer-BioNTech’s omicron-specific boosters. On Thursday, the Center for Disease Control and Prevention reviewed and approved the two shots,
Both could be available in pharmacies as early as this weekend. It all seems to be moving a bit fast considering that omicron started popping up only nine months ago—though also, given that new variants pop up all of the time, perhaps not fast enough. Here, we try to answer a bunch of questions you might have about the new shots.
What good will another round of boosters do?
“The vaccine effectiveness has decreased mostly in regards to symptomatic disease,” Taison Bell, an infectious disease physician at the University of Virginia, explained. “There’s still good protection against severe disease, at least for most people. But we want to make sure that we keep track of the virus as it’s changing so that our immune systems are in the best shape possible to deal with the present threat.”
These updated boosters will hopefully protect against both severe infections and infections more generally, says Robert Wachter, a Chair of the Department of Medicine at the University of California-San Francisco. The hope is also that the booster will allow for broader protection, as it trains the immune system to fight more than one kind of spike protein.
What do you mean more than one kind?
The new boosters are bivalent vaccines. Both companies’ shots have mRNA that encodes for the spike protein in BA.4/BA.5 (they are identical) and the spike protein of the original strain of the virus. As Bell explains, “they’re just changing some parts of the genetic code from the original mRNA but the other materials are the same. The original safety and efficacy should hold the same.”
Why bother continuing to protect against the 2020 strain?
To hedge our bets—there’s some possibility that there will be a new variant that resembles the original strain.
What if I’ve never gotten vaccinated? Should this be my first one?
If you’re one of the 30 or so percent of Americans that haven’t been fully vaccinated, you still have to get the original vaccine first. Right now, the new designs are only approved as boosters. But both Bell and Wachter suspect that the original vaccines could be taken off the market, and these new ones could become the primary vaccine. “We don’t want two different kinds of vaccines, one that’s updated and one that’s outdated,” Bell says.
Ok, so it will protect against coronavirus variants we’ve already seen…won’t there be another variant that’ll make this somewhat moot?
“It’s not just a question of whether there will be a new variant, because there probably will be,” Wachter says. However, the likelihood of a new variant that can evade a booster equipped with both BA.5 and original spike protein is low “but not 0” says Wachter. “You’re always taking educated guesses and the educated guess is ‘let’s have part of the vaccine focused on the variant that exists now in the hope that it stays the dominant variant for the next couple of months,” he says.
Speaking of weighing options… should I get the Moderna booster or the Pfizer booster?
The only real difference between the two vaccines is dosage, and who they are approved for. Moderna’s booster is a bigger dose, and is approved for those 18 years and older, and Pfizer’s, a smaller dose, is for individuals 12 and older. (Yet again, the younger kids will have to wait a bit longer for their shot.)
Jake Scott, a physician who specializes in infectious diseases, points out that protection against infection generated by the Moderna vaccine may last longer, as studies have shown, but there are more side effects with the Moderna shots due to the higher dose.
Bell says that he’s planning on signing his daughter up for the Pfizer booster, because she originally got Moderna and it made her a bit sick (though there isn’t specific data on side effects for the updated vaccines, he suspects they will be similar to those of the older version). But he emphasizes that it really doesn’t matter in the scheme of things which of the boosters you get: “If you need a car, it’s not gonna matter what model it is if you really need it. It’s a detail that’s not really necessary in the grand scheme of things. It’s just important you get an updated bivalent vaccine.” Scott notes that because most people getting the booster have already been vaccinated or infected, he thinks any difference in protection between the two is not going to be very significant.
I hear there haven’t been clinical trials for the new boosters…that’s…worrisome?
The concern here isn’t safety, it’s that it’s unclear how well the boosters will protect against infection.
“I have absolutely no safety concerns with the update,” said Bell, noting that the original safety data still applies to the updated vaccines. “You haven’t changed the manufacturing process,” notes Scott. We roll out slightly newer versions of vaccines all the time: Each year flu shots are updated to match the circulating strain, and most of the time they don’t have to go through clinical trials to show that the update is safe.
Both companies have submitted data as to how the vaccines fare against illness and infection in mice, but this data is not public yet. Human data is available for boosters targeting BA.1 (which was just approved in the UK); it showed that the shot was effective against preventing serious omicron illness. That bodes well as to how these latest boosters will fare against BA.5.
Ok, I’m on board. When should I get the booster?
The FDA recommends that the bivalent booster is administered at least two months following “primary or booster vaccination.” “For most people who have been boosted already, that timeline has already passed,” Bell notes. So, you could go get it now, by that logic.
But experts I spoke to point out that the FDA timeline doesn’t take into account infections, though they differed on the exact timeline to follow instead. “The immune system needs time to continue to refine itself and make improvements. It needs a good six months without interruption from another booster or even another infection to really produce an optimal response,” Scott says. Katelyn Jetelina, the author of the newsletter Your Local Epidemiologist, also advises waiting a little bit longer after either infection or vaccination—at least three months.
Rachel Gutman-Wei at The Atlantic wrote a great article about how to go about planning the timing of your next booster, that walks through what you should do based on when you were last infected—and, what to do if you’re high risk. Basically: if you haven’t had omicron, it’s smart to get the new booster now. If you’re like me and had omicron this summer, you could consider putting off getting the booster for a bit. Even if you didn’t have the very latest omicron subvariant, BA.2 infections can protect against BA.4 and BA.5.
Hmmm, I’m really worried about getting infected around the holidays. Is it worth waiting to get boosted, so I’ll have good protection then?
“You could make the argument to get the shot in October or November so you’ll have good protection through the winter when cases are likely to be higher and there will probably be some more human data,” Wachter says. “I’ll probably get mine when it’s ready because to me, it’s like an amateur trying to time the stock market, and you’re probably better off getting it when you’re eligible and going from there.”
“What I always tell people is you can’t schedule when you’re gonna get COVID,” Bell adds. “The best strategy is to get any and all boosters that are available to you, when they’re available to you. Get the protection you need now and worry about the future when the future comes.”
As ever, the bottom line is: just get vaccinated.
