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“You can’t rush safety,” said Dr. Yvonne Maldonado, a pediatric infectious diseases physician who is overseeing the Pfizer-BioNTech trial at Stanford University. Sometimes one dose — or even two doses — is not enough to boost immunity, she said. “It’s not that the first dose doesn’t work, it’s just that you may need more than one or two doses to make sure you get higher levels of protection. And so testing that takes time.”
It’s actually pretty common for young children to need multiple doses of a vaccine to get a big enough benefit, Dr. Maldonado said. The hepatitis B vaccine is given to children as three doses, while the diphtheria, tetanus and pertussis (DTaP) vaccine typically requires five doses.
The Coronavirus Pandemic: Key Things to Know
Some parents have wondered: If a two-dose regimen worked well for kids between 6 months and 2 years of age, why couldn’t the F.D.A. approve the vaccine just for that age group? Unfortunately, “it doesn’t work like that,” Dr. Levy said. “You can’t look at the results after the fact and say, ‘Oh, you know what? We change our mind about how we’re analyzing this. We’re just going to separate out a group, and you only need to approve things for this subgroup.’”
For similar reasons, parents can’t go to their child’s pediatrician to request a lower dose of the vaccine before it’s approved, Dr. Levy said. Vaccine doses are carefully reviewed and approved based on the risks and benefits to each age group.
The good news is that once the vaccine for kids under 5 is approved, the rollout should be much faster than it was for adults, Dr. Permar said, since pediatricians’ offices are already set up to receive and administer vaccinations. “I think we’re looking at late spring at this point,” she said.
And there’s still a lot you can do now to protect your family and prepare. If your child is afraid of needles, start getting them ready by teaching them relaxation techniques or reading them relevant books. If you’re concerned about how the Covid-19 vaccine will fit into your child’s regular shot schedule, or if you have questions about potential side effects, discuss it with your pediatrician, Dr. Langlois said.
And continue to follow public health measures like social distancing and masking where possible, as well as getting your older children vaccinated. According to data from the Centers for Disease Control and Prevention, only 24 percent of 5-to-11-year-olds and 57 percent of 12-to-17-year-olds have been fully vaccinated.
The coronavirus is still causing illness in young children and disrupting their lives, Dr. Langlois said, but parents should not give up hope. “We’re going to get there,” she said. “Parents, including myself, just need to be a little more patient.”