10 things to know about the bivalent COVID booster for kids under 5

This article appeared on the Michigan Health Blog. Read the full story here.

With the bivalent COVID booster recently authorized for children as young as six months, the updated coronavirus vaccine is now available to almost all age groups.

But as parents make decisions about vaccinating their child, some questions may be unclear: Which children are eligible? Should kids get the shot if they already had COVID? What are the side effects? Can you choose between vaccines?

Debra Langlois, M.D., a pediatrician at University of Michigan Health C.S. Mott Children’s Hospital and mother of two, helps answer these questions and more – and explains why she is choosing to get her own four-year-old daughter the bivalent booster.

1. Bivalent booster shots are the best protection against the predominant COVID-19 strain

These booster shots target both the original COVID-19 strain as well as subvariants of the omicron variant – which is the predominant circulating COVID-19 strain – providing the strongest protection to young children against what they’re most likely to be exposed to this season.

“These vaccines have been well studied, proven to be safe and effective and are responding to the current trends in COVID,” Langlois said. “The technology is there to provide us, and now almost all children, better protection against the predominant circulating Omicron variant strain.”

2. Eligibility depends on how many vaccinations a child has already had, and which kind

The COVID-19 vaccine only became available to young children in June, with Moderna offering a two-dose series for ages six months to six years and Pfizer offering a three-dose series for kids six months to under age five.

The United States Food and Drug Administration decided that children under age six who’ve already gotten two original doses of Moderna’s vaccine can get a single booster of Moderna’s bivalent vaccine if it’s been at least two months since their last shot.

Kids under age five who have started but not finished Pfizer’s vaccination series will get Pfizer’s original doses for the first two shots and Pfizer’s bivalent version for their third shot. However, those who have completed Pfizer’s three doses currently aren’t eligible for the bivalent booster. This may change after further reviews, Langlois says.

“The thought is that these children may already have some protection because when Pfizer was doing efficacy studies for their third dose, we were seeing Omicron as the predominant strain,” Langlois said, noting that data to support giving an updated bivalent booster dose for these children is expected in early 2023.

All COVID-19 series doses should be from the same manufacturer in this age group, and the bivalent booster is now the only option available as the third shot.

3. Side effects are minor and temporary

No safety concerns have come up in either trial and reported side effects are comparable to routine vaccines, including potential swelling or redness or pain at the injection site, temporary elevated temperature, fatigue, or irritability for a day or two for younger kids. Some kids have no side effects.

Ibuprofen or acetaminophen can reduce pain, fever and discomfort, Langlois says.

4. Children who have had COVID should still get vaccinated

The Centers for Disease Control and Prevention recommends the bivalent booster for all children who are eligible. But if a child recently contracted COVID, parents may consider delaying their next vaccine dose up to three months from when symptoms started or they tested positive.

“We know that you have some natural immunity after a COVID illness, but we aren’t sure exactly how long that lasts,” Langlois said. “COVID vaccines, including the bivalent vaccine, offer longer lasting protection. To ensure kids are protected against the virus, all eligible children should get vaccinated.”

5. If your child has cold-like symptoms but has tested negative for COVID, they can still get the shot

“If you think your child might have COVID, or if your child has COVID, you should still be isolating them per CDC guidelines to protect the community,” Langlois said. “But with so much going around right now, sniffles or minor cold symptoms shouldn’t necessarily prevent you from getting them vaccinated if they’ve tested negative for COVID and are fever-free for at least 24 hours without the use of ibuprofen or acetaminophen.”

“Preventative care is more important than ever as we see both COVID and other seasonal viruses circulating.”

However, if little ones aren’t feeling well, parents may decide to wait until they’re feeling better to go get a shot.

6. The vaccine dose is smaller than the one for older kids and based on age

COVID-19 bivalent vaccine dosage is based on the child’s age on the day of vaccination, not on a child’s size or weight – which is also the case for the primary COVID vaccination series.

If a child is on the cusp of any of the age ranges for the bivalent booster, they should be vaccinated as soon as possible, and they should receive the dose recommended for their age on the day of their visit.

7. Vaccines are still the best protection against severe COVID illness

While many kids have mild illness from COVID-19, others may get seriously sick and hospitalized.

During the omicron surge beginning in late December 2021, children ages four and under were hospitalized at nearly five times the rate of the previous peak when Delta was the predominant strain, according to the CDC.

The CDC also reports more than 9,000 children have had an illness meeting the definition of the rare but serious COVID-linked condition multisystem inflammatory syndrome, or MIS-C, including more than 70 deaths as of Nov. 28. MIS-C causes severe inflammation in vital organs and tissues, and without treatment, could be life-threatening.

“As a mom of a young child, I don’t want to take that chance,” Langlois said. “We still can’t predict every child that is going to experience the most serious illnesses from a COVID infection. But we have vaccination, which is a safe and effective tool to protect them.”

8. Children can safely receive other vaccines the same day they receive their COVID-19 vaccine

Children can get different vaccines on the same day, including shots like COVID-19, influenza and other routine vaccines.

“It’s safe to get vaccines at the same time. Vaccination is a critical piece of preventive care that shouldn’t be delayed,” Langlois said.

The flu shot is recommended every season, she adds.

”We are experiencing a respiratory virus surge, and we have safe and effective vaccines to protect against two circulating respiratory viruses, COVID-19 and influenza,” she said.

9. Higher vaccination rates for younger ages help protect all

Children’s hospitals are experiencing record surges of respiratory viruses like respiratory syncytial virus, or RSV, and are starting to see influenza cases as well, keeping emergency departments and hospital units full. The more children protected against illnesses that have vaccines available, including COVID-19 and flu, the less strain on healthcare resources.

“With winter weather bringing more people indoors and upticks in both seasonal viruses and COVID, we want to keep as many children healthy as possible to keep from overwhelming our health systems,” Langlois said. “Fewer sick kids mean less burden on our hospitals and clinics, so our health care teams can continue to care for the diverse needs of all of our patients.”

She notes that as people plan holiday gatherings and travel, they should also consider vaccination to protect loved ones, including the elderly and immunocompromised who may have higher risks of complications from COVID.

“We’re not only protecting our children with the most up-to-date, evidence-based vaccine, we’re also protecting our families and communities,” she said.

10. If you have questions, talk to your doctor

Parents may understandably continue to have questions before deciding to vaccinate their kids, and Langlois encourages them to have these conversations with their child’s primary providers.

“Talk to your child’s doctor. That’s what we’re here for,” Langlois said. “We care about your children, we want to make sure you’re receiving the most up-to-date reputable information, and we want to answer any questions you may have about vaccinating your child.”

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You’ve got questions. That’s a good thing.

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You’ve got questions. That’s a good thing.

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