Dr. Rochelle Walensky, the director of the Centers for Disease Control and Prevention, has signed off on two COVID-19 vaccines for children over 6 months of age and under 5.
Millions of U.S. parents — including many of my friends with children under 5 — were crossing their fingers again this week, hoping the vaccines would soon be available for younger age groups. An advisory panel to the Food and Drug Administration voted unanimously last Wednesday to recommend that the agency authorize the Pfizer-BioNTech and Moderna vaccines for use in very young children. On Friday and Saturday, advisers to the CDC met to discuss and voted yes unanimously.
After multiple delays in the review process of Pfizer’s vaccine, both vaccines are expected to become available early next week. The Pfizer vaccine will cover children ages 6 months through 4 years old, and the Moderna vaccine will cover children ages 6 months through 5 years old.
Understandably, many parents of young children have questions about the vaccines and the expected rollout. I talked with three infectious disease pediatricians to get answers.
Q: How do the Moderna and Pfizer vaccines differ?
A: The Moderna vaccine is authorized as two doses spaced four weeks apart, said Dr. Debbie-Ann Shirley, a pediatric infectious disease physician at the University of Virginia. Pfizer is authorized as a three-dose series, with the first two shots spaced three weeks apart, and the third shot given at least eight weeks later. (Pfizer’s third shot is not considered a booster. It’s likely that Moderna and Pfizer will eventually authorize an additional booster dose for young children.) Both vaccines are at lower doses than the vaccines given to older kids and adults.
Preliminary data released by Moderna in April suggested that two shots were 51% effective at preventing symptomatic COVID-19 infection among children ages 6 months through 1 year, and that two shots were 37% effective at preventing infection among kids ages 2 through 5 years. Pfizer claimed that its three-dose series had an efficacy of 80% at preventing COVID-19 infection among kids ages 6 months through 4 years old, but that estimate was based on infections in just three children.
Q: What are the side effects of the vaccines in young kids?
A: The data so far suggest that the side effects in younger kids are milder than those in older kids, probably because a lower dose of the vaccine is given, Shirley said. Among children under 5, “the side effects were the sorts of things that we might expect in children after receiving a vaccine,” she added, including increased fussiness, sleepiness and pain at the injection site. Comparing the two vaccines, Pfizer’s resulted in fewer side effects overall, probably because it uses such a low dose.
No children in the vaccine trials developed heart issues like myocarditis, a form of heart inflammation that was seen in a small number of older children who received the vaccine, Shirley said, but this could be because the trials were not big enough to detect rare side-effects. It’s possible there will be some cases once the vaccines are given to enough kids, but experts don’t expect to see a significant number, because myocarditis “occurs more frequently in teenagers and young adults than younger kids,” said Dr. Ibukun Kalu, an infectious disease pediatrician at the Duke University School of Medicine.
“I would not expect high rates of vaccine-related myocarditis in the under 5s,” she added. Kalu also pointed out that the risk of myocarditis is much higher among kids who catch COVID-19 than it is among those who get the vaccine.
It’s important to note that when the FDA did not authorize the two-dose Pfizer vaccine back in February, that was because it didn’t work well enough, not because of any safety issues. (And that’s ultimately why the vaccine now has a three-dose regimen.)
Q: Should your child get vaccinated right away if they’ve recently had COVID-19?
A: According to the CDC, kids who recently had COVID can get the vaccine as soon as they are out of isolation and are feeling better, Kalu said. But because “reinfection appears to be rare after the first few months of recovering from a COVID infection,” Shirley added, it’s not unreasonable to wait up to 90 days after the infection before getting them vaccinated.
Still, you may want to get them the shot sooner if cases are climbing in your community, if you’re traveling to areas with high COVID rates, or if your child is immunocompromised or has underlying risk factors, Shirley said. If you’re not sure what to do, “reaching out to a trusted health care provider is always a good way to talk through some of those issues,” she added.
Q: COVID-19 symptoms are often mild in young kids, and they can get the virus even if they’re vaccinated, so what’s the point of vaccinating my young child?
A: It’s true that COVID-19 is far less risky for kids than it is for those who are older. But more than 440 children ages 4 and under have died from COVID-19 since January 2020, and the infection is “one of the top 10 causes of death in children in the United States,” said Dr. Yvonne Maldonado, a pediatric infectious disease physician at Stanford Medicine who chairs the American Academy of Pediatrics’ committee on infectious diseases. Also, COVID-related hospitalization rates are higher for children 4 and younger than they are for older children, and more than half of pediatric hospitalizations among kids ages 6 months through 4 years occur in children with no known underlying risk factors. “I’ve had a number of friends who are health care providers whose children have wound up in the hospital, some on oxygen in the ICU, who have no risk factors,” Maldonado said.
“Vaccines are the most effective way that we have as clinicians to help prevent patients from developing severe forms of COVID,” Shirley said — and that includes little kids.