This article has been updated with the latest information. It came just weeks after Pfizer and Moderna both applied for emergency use authorizations (EUA) for their boosters, which target the BA.4/BA.5 variants. Originally, Moderna’s bivalent booster was targeted for use in people 18 and older, while Pfizer-BioNTech’s shot was made available for people 12 and up. Tweens and teens were among the first children eligible for the updated booster. But those ages have since been expanded. In a statement, CDC Director Rochelle Walensky, MD, MPH, said, “the updated COVID-19 boosters are formulated to better protect against the most recently circulating COVID-19 variant.” She goes on to add, “if you are eligible, there is no bad time to get your COVID-19 booster and I strongly encourage you to receive it.” With this news, parents understandably have lots of questions. With kids in school and germs circulating, parents want to know how to time their kids’ boosters.

Is My Child Eligible for the Bivalent Booster?

Pfizer’s vaccine for kids aged 12 and up was rolled out in the days and weeks after Labor Day 2022, just in time for many children to head back to school. Moderna soon followed with its vaccine for that age group. By October, the FDA authorized the updated bivalent boosters from Pfizer and Moderna for everyone ages 5 and older. The Pfizer booster was made available for kids 5 and up, and the Moderna booster was for kids 6 and up. Kids can get these boosters two months after completing their primary series or last booster. Then in December, officials added parameters for those over 6 months old. The updated Moderna bivalent booster can be given to any child over 6 months old who completed their primary series of the original vaccine at least two months ago. “More children now have the opportunity to update their protection against COVID-19 with a bivalent COVID-19 vaccine, and we encourage parents and caregivers of those eligible to consider doing so—especially as we head into the holidays and winter months where more time will be spent indoors,” FDA Commissioner Robert M. Califf, MD, says in a statement. For Pfizer, children between 6 months and 4 years old that have not yet had any COVID vaccinations—or have not yet gotten a third dose—will receive the bivalent booster as part of their primary series. But, this is important: Children between 6 months and 4 years old who have already had three doses of the original vaccine will not be eligible to get a bivalent booster dose at this time. The FDA says they expect more data for this group in January and will evaluate it then.

What to Know About the Omicron-Specific Boosters

The bivalent booster combines the BA.4/BA.5 variants with the original vaccine formula. For kids 12 and up, the dose is the same for this booster as it was for other Pfizer boosters: a 30-µg dose. As such, experts expect any potential side effects of this vaccine will be similar to the original. “The expected side effect profile would be very similar to the original vaccine because the mRNA vaccine technology is the same for both,” explains Kari Simonsen, MD, MBA, senior vice president, pediatrician-in-chief, and chair of pediatrics at Children’s Hospital & Medical Center in Omaha, Nebraska. According to the FDA, in a clinical study of the original Moderna booster, common side effects for those ages 17 through 36 months included irritability/crying, sleepiness, and loss of appetite. For those between 37 months and 5 years, other side effects were fatigue, headache, muscle pain, joint pain, chills, and nausea.

What Are the Benefits of the New Booster for Kids?

Experts agree this new bivalent vaccine will have many benefits for kids who are eligible to receive it. First of all, vaccines and boosters generally protect kids from the most serious effects of a COVID-19 infection. “The vaccines reduce the risk of death and serious illness from COVID-19,” says Ali Alhassani, MD, MSc, head of clinical at Summer Health. “While it is true that death due to COVID-19 is extremely rare in children, the risk is not zero.” Additionally, Dr. Alhassani says COVID vaccines and boosters have shown protection against serious COVID complications such as MIS-C (multisystem inflammatory syndrome in children). Vaccines also make kids less likely to contract COVID and spread the infection to vulnerable people, he adds. The fact that these new boosters are updated with the currently circulating variants means they will likely have broader protection than the boosters based on the original formula, says Dr. Alhassani. “These new boosters are targeted for the Omicron BA.4/BA.5 variant, the dominant strains in the U.S.,” he explains. “That fact suggests that they would offer broader protection than the first Pfizer-BioNTech vaccine that targeted the initial COVID-19 strain alone.”

When Should I Get My Child Boosted?

Vaccination rates for children in the younger age groups are relatively low. As of November 30, 2022, less than 5% of kids between the ages of 2 and 4 years old have completed their primary series, according to the CDC. That number is even lower for those under 2 years old, at just under 3%. Only 2% of children ages 5 to 11 have gotten their bivalent booster. Given these numbers, health officials are hoping to encourage more parents to not only get their children boosted but also vaccinated if they haven’t already—and do it as soon as possible. “Parents and caregivers can be assured that the FDA has taken a great deal of care in our review, and we encourage parents of children of any age who are eligible for primary vaccination or a bivalent COVID-19 vaccine booster dose to consider seeking vaccination now as it can potentially help protect them from COVID-19 during a time when cases are increasing,” says Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research. Behnoosh Afghani, MD, a pediatric infectious diseases specialist at UCI Health, doesn’t think parents should wait on boosting their kids, noting that booster doses of COVID vaccines have been shown to decrease disease severity in kids.  “Because of the high prevalence of circulating COVID-19, it is important for the kids who qualify for the booster dose to get it as soon as possible.” Dr. Afghani adds. If you have any questions about COVID vaccinations or boosters, make sure to discuss the decision with your child’s pediatrician or another healthcare provider, especially if your child has any underlying medical conditions.