A booster shot raises the level of protection against omicron, Fauci says. How to choose a COVID-19 booster – CNET

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With the new omicron coronavirus variant in the US, experts are strengthening their call for coronavirus boosters as maximum protection against severe COVID-19. In an interview with ABC on Sunday, Dr. Anthony Fauci, President Joe Biden’s Chief Medical Advisor, said that while omicron “appears to be able to evade some of the immune protection” from COVID-19 treatments and vaccines, receiving a booster shot “raises the level of protection high enough that it then does do well against the omicron,” he says. 

While the definition of fully vaccinated hasn’t changed for the time being, receiving a third dose (or second, in the case of people who received Johnson & Johnson) seems to bring back some protection lost with the newer coronavirus variant. “If you look at the data, the more and more it becomes clear that if you want to be optimally protected, you really should get a booster,” Fauci said. 

With the expectation that omicron would reach the US and add to the wave of COVID-19 cases caused by the delta variant, the Centers for Disease Control and Prevention strengthened its recommendation in late November that all US adults “should” get a booster. (Though all adults have been eligible since mid-November, the CDC previously split hairs over who “should” get one and who “may” get a booster.) More data is needed on the omicron variant, but officials are predicting omicron is at least as contagious (if not more) as the delta variant, but possibly less severe compared to delta. However, that preliminary data has “confounding issues,” Fauci said, and more time is needed to collect information. 

Even if omicron does end up causing less severe disease, on average, compared to delta, large numbers of people contracting COVID-19 at once could overwhelm hospital systems and the resources required to treat patients.

The booster rollout, and the idea of giving extra shots to otherwise healthy adults, has been a controversial one. Just 7.1% of people in low-income countries have received a coronavirus vaccine, according to Our World in Data. The Biden administration has said the US can continue vaccine donations to other countries while also providing boosters to Americans, pledging to donate 1.2 billion doses. On Dec. 7, White House COVID-19 Response Team Coordinator Jeff Zients said the US has now donated 300 million doses of COVID-19 vaccine

All adults can get any of the three available COVID-19 vaccines in the US as a booster shot — a “mix and match” approach to COVID-19 vaccines. Currently, the CDC doesn’t have a “product preference” on one booster over the others — noting that it’s generally recommended to stick to the same brand for primary and second vaccine series, but people can choose whichever booster they’d like or is available to them. 

As the booster rollout intensifies, here’s what to consider when choosing your extra dose. 

Are the boosters effective against omicron?

Pfizer and its partner BioNTech announced Wednesday that two doses of their vaccine appear to be less protective against COVID-19, but a booster dose restores some of that power. Officials at BioNTech also said Wednesday that the companies could have an omicron-specific vaccine ready by March 2022, if research shows it’s needed. Moderna said it’s studying the effectiveness of its vaccine and could make an omicron-specific vaccine if necessary. Johnson & Johnson said it’s working with officials in South Africa to evaluate its vaccine’s effectiveness and also started work on a vaccine specific to omicron, if it’s needed. 

In an interview with NBC from Nov. 28, Fauci said that even in the face of a variant of concern, you do well against it if you have the increased protection of a booster. “It may not be as good in protecting against initial infection, but it has a very important impact on diminishing the likelihood that you’re gonna get a severe outcome from it,” he said, adding that boosting gives an “extraordinary increase in protection.” 

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What’s the difference among the COVID-19 vaccines? 

While all three vaccines have the same effect — protection against severe COVID-19 disease — the way they function is a little different. Pfizer and Moderna are mRNA vaccines, which teach our cells to make a specific protein and build immunity against a virus. Johnson & Johnson is a viral vector vaccine, which uses a harmless virus to activate an immune response and tell our bodies what to fight in future infections. 

Both vaccine types prepare our immune systems for COVID-19 infection, and none of the coronavirus vaccines infects us with the actual coronavirus

What are the benefits of ‘mixing and matching’ COVID-19 boosters?

Individual choice in boosters means health care providers can make recommendations based on patients’ circumstances, and also allow people to get whatever vaccine is most convenient to them. A member of the CDC’s advisory panel, which meets prior to recommending a vaccine or booster, pointed out at a meeting about mixed boosters that allowing it could lead to fewer doses being wasted if health care providers only have to open one bottle of vaccine for patients in the waiting room, for example. Hopefully, more flexibility with boosters will lead to an easier vaccination process in places that administer many doses at once, such as nursing homes. People may also opt for a different vaccine if they’re at higher risk for a rare side effect from a particular vaccine.

In a study published in the journal Nature in May, researchers in Spain found that people who received one dose of AstraZeneca (a similar vaccine to Johnson & Johnson) and then received a dose of Pfizer seem to produce a higher antibody response than people who receive two doses of AstraZeneca. It isn’t clear whether this group had a higher immune response than people who received two doses of Pfizer. 

Research published recently in The Lancet (which tested seven vaccines from around the world as boosters, including the three available in the US) showed that mixing COVID-19 vaccines for boosters is effective, with mRNA vaccines producing the biggest response

Early research funded by the National Institutes of Health prior to the CDC’s recommendation also found that mixing vaccines is safe and effective, or perhaps even beneficial in some cases. 

According to booster data on primary series and booster choice the CDC is collecting, over 4 million Americans so far have opted for a different vaccine brand as a booster. (Most have chosen their original vaccine as a booster.) Countries outside the US have been officially allowing (or even recommending) people receive two different vaccines as a primary series, including Germany, Canada, Sweden, France, Spain and Italy.

Which booster shot should I get if I got Pfizer?

Both mRNA vaccines, Pfizer and Moderna, have proven to be effective and continue to protect against severe disease caused by COVID-19. A study published by the CDC in September that compared vaccine effectiveness among adults in the real world found that two doses of Moderna’s vaccine were 93% effective at preventing hospitalization, two doses of Pfizer were 88% effective and one dose of Johnson & Johnson was 71% effective. 

Pfizer’s booster is the same dose as its original vaccine (30 micrograms), while Moderna’s booster (50 micrograms) is half the size of its original vaccine. Johnson & Johnson’s booster is also the same size as its original vaccine. In a study that examined people’s responses to all three vaccines as boosters, people who originally got Pfizer had the strongest antibody response to a Moderna booster. However, that study examined a full dose of Moderna (100 micrograms), rather than the authorized half-dose of the company’s booster, which likely minimizes Moderna’s edge over Pfizer, The Atlantic reported. 

Read more: Pfizer COVID booster gets CDC approval for all adults

For most adults who were vaccinated with Pfizer, sticking with another dose of Pfizer makes the most sense, Dr. Robert Wachter, chair of UC San Francisco’s Department of Medicine, told the Los Angeles Times.

“I got Pfizer and stuck with getting another Pfizer — just seemed simpler. Why introduce a new agent into my body for probably zero, or maybe tiny, benefit?” he told the LA Times. “But if your goal were to give yourself any possible advantage in immunity, you can make an argument to switch to Moderna.”

If you’re in a group that would benefit most from every inch of immunity (which includes the elderly and people with health conditions that make them most susceptible to severe COVID-19), it might be worth a quick call to your health care provider to discuss your personal circumstances. However, the urgency of a new variant might also influence your decision, which includes what’s available to you the soonest. 

Teens as young as 16, who are now eligible for Pfizer’s booster after the CDC recommended boosters for 16- and 17-year-olds, will need to stick with Pfizer for a third dose as Moderna and Johnson & Johnson aren’t authorized for anyone under age 18 yet. 

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The definition of “fully vaccinated” hasn’t changed. A person is considered fully vaccinated two weeks after their second dose of Pfizer or Moderna, or two weeks after a single dose of Johnson & Johnson. 


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What if I got Moderna? 

Similar to Pfizer, most Moderna recipients probably don’t have a need to choose a different booster, unless how quickly they can get an appointment is an issue.

There might be exceptions — if you had an allergic reaction to Moderna’s vaccine, for example, you should consult a doctor and choose a different vaccine for future shots. An early report on Canadian data also suggested Moderna might carry a higher risk of myocarditis, an uncommon side effect of the mRNA vaccines mostly seen in men under 30, compared to Pfizer. With this assumption, a man under 30 who originally received Moderna but is concerned about myocarditis may ask a health care provider about switching to Johnson & Johnson or Pfizer. But again, Moderna’s booster is a smaller dose than its original vaccine, which could be a factor in your decision. 

Read more: Moderna COVID booster recommended for all adults. What to know 

Which booster should I get after J&J? 

Some public health experts have argued that a second shot for people who got Johnson & Johnson is more like completing the series, rather than getting a booster. In a clinical trial shared by Johnson & Johnson, a second dose of J&J two months after the first shot made the vaccine 94% protective against symptomatic COVID-19. However, some experts also argue that Johnson & Johnson recipients are better off choosing either mRNA vaccine while pointing to a different study that showed higher antibody responses following a boost of mRNA vaccine compared with a boost of J&J. (Antibody response is not the only element of immunity, however.)

Women under 50 who originally got J&J should be especially aware of the availability of other vaccines, the CDC says, because they’re at an increased risk for the rare but serious blood-clotting disorder associated with J&J’s vaccine (which isn’t seen with Pfizer’s or Moderna’s). For example, Dr. Leana Wen, physician and public health professor at the Milken Institute School of Public Health at the George Washington University, detailed her decision to get a Pfizer booster after being vaccinated with Johnson & Johnson in a report for The Washington Post

Older men who might be at an increased risk of the rare neurological disorder associated with J&J’s vaccine may also choose another type of vaccine. In general, people who originally received Johnson & Johnson’s vaccine and have a health condition that makes them more susceptible to severe COVID-19 should be especially aware of the benefits of mixing with an mRNA vaccine and the higher immune response it seems to bring. 

Read more: Everything to know Johnson & Johnson COVID boosters

Do I have to get a booster? 

The CDC’s recommendation is that all adults in the US “should” get a booster. This is because even if the omicron variant lowers the efficacy of the vaccines, scientists expect COVID-19 vaccines to remain protective against severe disease.  

Before omicron, earlier in November, the CDC advisory panel voted unanimously to recommend boosters for all adults, but they also acknowledged that some people need them more than others. The guidance was that people age 50 and older “should” get a booster (a younger age than the previous guidance for everyone age 65 and older), in addition to other groups who “should” get one because of a clearer benefit, including adults living in long-term care facilities and everyone who received Johnson & Johnson’s vaccine. For all other adults, the choice was more dependent on personal circumstances or preference. Because of the newer variant which may increase risk of infection in people who already had COVID-19 or those who are fully vaccinated, officials are calling for maximum protection for everyone eligible — age 16 and up. 

Are you fully vaccinated after your booster? 

Importantly, the definition of fully vaccinated hasn’t changed (though it might in the future). You’re still fully vaccinated two weeks after your second Pfizer or Moderna shot or two weeks after your Johnson & Johnson vaccine. Whether someone has received a booster doesn’t affect their “fully vaccinated” status. 

Can I mix and match the first two shots?

No, the CDC’s statement on mixing COVID-19 vaccines only applies to boosters. As of now, the FDA has only authorized a mixed-series booster, meaning the first coronavirus vaccine series must be one dose of Johnson & Johnson or two doses of Moderna or Pfizer. 

Once the mixed-series boosters start rolling out to Americans in greater numbers, there will be more data on the safety and effectiveness of a mixed COVID-19 series. Although it might be too early to hope, this might mean that data on mixing for boosters will inform decisions on primary coronavirus vaccine series being used together, making it easier to reach underserved communities, and possibly reducing health care and vaccine inequity.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.