covid booster shot

COVID Booster Shots: Here's Who is Eligible for a Fourth Vaccine Dose

The federal government is soon expected to evaluate whether to recommend fourth vaccine doses for all Americans

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Millions of Americans can now receive a second COVID-19 booster shot, but who specifically is eligible?

If you don't qualify yet, when may you be able to get your second booster?

Here's a breakdown of eligibility, why health officials say another shot is necessary for some and when others may be able to receive one:

Who is eligible for a second COVID booster shot?

Americans 50 and older can get a second COVID-19 booster if it’s been at least four months since their last vaccination.

The Food and Drug Administration last week authorized an extra dose of the Pfizer or Moderna vaccine for that age group and for certain younger people with severely weakened immune systems.

The Centers for Disease Control and Prevention later recommended the extra shot as an option but stopped short of urging that those eligible rush out and get it right away. That decision expands the additional booster to millions more Americans.

For the more than 4 million who got Moderna or Pfizer as their second shot, the CDC says an additional booster is only necessary if they meet the newest criteria — a severely weakened immune system or are 50 or older.

Until now, the FDA had allowed a fourth vaccine dose only for the immune-compromised as young as 12. Only the Pfizer vaccine can be used in those as young as 12; Moderna's is for adults.

What about those who got the Johnson & Johnson vaccine?

People who received the single-dose Johnson & Johnson vaccine. were eligible for one booster of any kind. Of the 1.3 million who got a second J&J shot, the CDC said now they may choose a third dose — either Moderna or Pfizer.

That's because a CDC study that tracked which boosters J&J recipients initially chose concluded a Moderna or Pfizer second shot was superior to a second J&J dose.

What about the rest of the population?

The federal government is expected to evaluate whether to recommend fourth vaccine doses for all Americans, and could choose to issue those recommendations during the fall when more Americans are indoors as the weather cools.

This week, the government will hold a public meeting to debate if everyone eventually needs a fourth dose, possibly in the fall, of the original vaccine or an updated shot.

Even if higher-risk Americans get boosted now, Marks said they may need yet another dose in the fall if regulators decide to tweak the vaccine.

For that effort, studies in people — of omicron-targeted shots alone or in combination with the original vaccine — are underway. The National Institutes of Health recently tested monkeys and found “no significant advantage” to using a booster that targets just omicron.

Why do people need a second booster?

Dr. Rochelle Walensky, CDC's director, said it was especially important for older Americans — those 65 and older — and the 50-somethings with chronic illnesses such as heart disease or diabetes to consider another shot.

“They are the most likely to benefit from receiving an additional booster dose at this time,” Walensky said.

There's evidence protection can wane particularly in higher-risk groups, and for them another booster “will help save lives,” FDA vaccine chief Dr. Peter Marks said.

The move toward additional boosters comes at a time of great uncertainty, with limited evidence to tell how much benefit an extra dose right now could offer. COVID-19 cases have dropped to low levels in the U.S., but all vaccines are less powerful against newer mutants than earlier versions of the virus — and health officials are warily watching an omicron sibling that's causing worrisome jumps in infections in other countries.

During the U.S. omicron wave, two doses were nearly 80% effective against needing a ventilator or death — and a booster pushed that protection to 94%, the CDC recently reported. Vaccine effectiveness was lowest — 74% — in immune-compromised people, the vast majority of whom hadn’t gotten a third dose.

To evaluate an extra booster, U.S. officials looked to Israel, which opened a fourth dose to people 60 and older during the omicron surge. The FDA said no new safety concerns emerged in a review of 700,000 fourth doses administered.

Preliminary data posted online last week suggested some benefit: Israeli researchers counted 92 deaths among more than 328,000 people who got the extra shot, compared to 232 deaths among 234,000 people who skipped the fourth dose.

What’s far from clear is how long any extra benefit from another booster would last, and thus when to get it.

“The ‘when’ is a really difficult part. Ideally we would time booster doses right before surges but we don’t always know when that’s going to be,” said Dr. William Moss, a vaccine expert at the Johns Hopkins Bloomberg School of Public Health.

What are the side effects of a second booster dose?

Dr. Pamela Vergara-Rodriguez, with Cook County Health, said the side effects likely won't differ from the original doses and initial booster dose.

"We are expecting that the adverse side effects that we're all aware of that can occur after we get any vaccine can continue to occur," she said.

That includes things like fatigue, feeling ill, a fever or pain at the infection site, she said.

The CDC stated that side effects with booster shots "were similar to that of the two-dose series."

The most common symptoms include fatigue and pain at the injection site, but "most symptoms were mild to moderate."

As with previous doses of the vaccine, the CDC notes that, "serious side effects are rare, but may occur."

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