CDC advisers recommend Pfizer, Moderna Covid-19 vaccine for babies and toddlers

The Centers for Disease Control and Prevention’s vaccine advisory group on Saturday voted unanimously to recommend both the Pfizer-BioNTech and Moderna mRNA vaccine for kids 6 months to 5 years old.

"This infection kills children, and we have an opportunity to prevent that," said Beth Bell, a professor at the University of Washington's School of Public Health and voting member.

Should the CDC’s director, Rochelle Walensky follow her advisory committee’s recommendation as expected, children in this age group will be able to begin receiving vaccines as soon as next week.

Independent advisers recommended children 6 months to 4 years old receive three doses of the Pfizer-BioNTech 3-microgram vaccine. The first two doses should be three weeks apart, followed by a third dose at least eight weeks later. For now, children with a compromised immune system will not receive an additional dose, though the expert panel noted this group may need an additional dose for optimal protection.

The advisers also recommended children 6 months to 5 years old receive two doses of Moderna’s 25-microgram vaccine four weeks apart. Additionally, children with certain kinds of compromised immune systems may receive a third dose of Moderna’s vaccine at least one month following their second dose.

Both vaccines generated an immune response comparable with young adults who received two full doses without serious side effects. Moderna’s two-dose vaccine, which was studied through the height of the Omicron surge, appeared to reduce Covid-19 cases by an average of 41.5 percent, which researchers noted was roughly on par with vaccine effectiveness in adults during that time. Data from Pfizer and BioNTech showed the three-dose series had an 80 percent efficacy, but because of the small number of Covid-19 cases in the data Pfizer presented, advisers cast some doubt on that figure.

The studies on both vaccines weren't large enough to confirm whether the vaccines prevent against hospitalization and death. But given that both of these vaccines reduce hospitalizations and death for older children and adults, representatives from the CDC believed it was safe to assume that they would.

The Food and Drug Administration authorized both vaccines for the youngest children on Friday, following a meeting of its advisory committee, which unanimously endorsed the vaccines.

Background: Between March 2020 and mid-June 2022, there were roughly 2.5 million cases of Covid-19 in children 4 years old and younger, and more than 200 deaths. During the Omicron wave, Covid-19-related hospitalizations among this age group surpassed older children, even without co-morbidities. Data presented by the CDC also showed that while roughly 71 percent of children under 4 show evidence of prior Covid-19 infection, it doesn't appear that these prior infections offer adequate protection against future disease.

Less than a third of U.S. children aged 5-11 years old have been vaccinated so far. Polling conducted by the Kaiser Family Foundation showed that while 20 percent of parents are eager to vaccinate their children under 5, some 40 percent of parents are reluctant to vaccinate their babies and toddlers at all.

Representatives from the CDC also noted that they believed Covid-19 vaccines for these age groups could be administered with other vaccines, potentially saving parents and children trips to their health care providers. "We have extensive experience with non-Covid-19 vaccines that have demonstrated ... adverse event profiles are generally similar when vaccines are administered simultaneously as when they are administered alone," said Sara Oliver, the lead for the Covid-19 vaccines for the Advisory Committee on Immunization Practices work group within the CDC. Given the limited data on co-administering Covid-19 vaccines with others, though, she added that "providers can make decisions about administration on a case-by-case basis."

Advisers also considered whether it would be possible to mix vaccines in this age group. The CDC's clinical considerations team decided that it would issue guidance for practitioners saying that mixing between the two vaccines was acceptable, provided that a child received three doses total. If a child received two doses of the Moderna vaccine, they would be considered up-to-date.

On Thursday, Assistant HHS Secretary for Preparedness and Response Dawn O’Connell said that state and local healthcare providers have ordered roughly 2.5 million doses of the Pfizer-BioNTech vaccine for babies and toddlers and 1.3 million doses of Moderna’s — about half and a quarter of the doses the federal government has made available, respectively. All 50 states have pre-ordered vaccines, including Florida as of Friday. Representatives from the CDC said they expect provider orders to uptick after seeing the discussions around the recommendations today.

What’s next: Walensky is expected to endorse the vaccines shortly.

The agency’s vaccine advisers will meet on June 23 to discuss Moderna’s vaccine for children 6 to 17 years old, which has already been authorized by the FDA. Kids in this age group may already receive the Pfizer-BioNTech mRNA vaccine.