A vaccine for the youngest children brings hope, confusion, concern

For some parents struggling through another pandemic winter, a COVID-19 vaccine for children younger than 5 cannot come soon enough.

But the rush to authorize a vaccine that produced disappointing results in a clinical trial of children that age has left more than a few parents struggling to understand whether vaccinations will be worth it for the youngest kids, an often wrenching calculation.

“It all seems so very confusing to me,” said Katie Medeiros, a Woburn mother of two children, including a 3-year-old. “I feel like I need some more concrete evidence to say this is something I’m going to definitely give my child.”

Children are far less likely to become seriously ill from a COVID-19 infection than adults, and parents already have shown hesitancy in vaccinating older children, ages 5-11. In Massachusetts, just over half of that age group has received one shot, according to the latest figures, compared to more than 82 percent of adolescents and teens.

A recent national survey showed that confidence in vaccinations among parents of children under 5 had declined in recent months, and a clinical trial — though it showed no safety concerns — did not produce the hoped-for immune response in children ages 2 to 4.

Despite that setback, federal regulators prodded Pfizer and its German partner, BioNTech, to apply last week for emergency authorization for two doses of its messenger RNA vaccine for children 4 and younger. Two doses in children between 6 months and 2 years old did stimulate a response comparable to that of older teenagers and young adults.

On Friday, the Food and Drug Administration plans to share data from the Pfizer-BioNTech trial, detailing for the first time how much protection the vaccine did provide to children 2 to 4 years old.

On Tuesday, an independent panel of scientific advisers to the FDA is scheduled to vote on whether to recommend that the agency authorize the vaccine while awaiting the results of a follow-up study to see if adding a third shot produces the hoped-for immunity levels. Those results aren’t expected for a few weeks, possibly not until the end of March.

The wait has been excruciating for parents like Katherine Monteiro, an Andover mother who switched jobs and kept her daughter out of preschool for a year in an attempt to keep COVID out of her home and away from her father-in-law, who is immunocompromised.

Asked how soon she would like to have her 4-year-old daughter vaccinated, Monteiro said, “Last week would be great.”

“We have not done any sort of vacations. We’ve not done most holidays,” she said. “We’re just super, super cautious.”

Since her daughter is healthy and the vaccines have not raised safety concerns, she considers the virus a more unknowable risk than the vaccine.

“I know that some people are concerned with side effects, but I’m really not, especially when you look at the science behind it,” she said. “Why are we waiting?”

But other parents who are similarly eager for a vaccine for their children are unsatisfied with the information they’ve gotten so far. Alexis Minkkinen, who quit her restaurant job at the start of the pandemic and has been cooped up in her Revere apartment ever since with her husband and daughter, now 2½, said she will ultimately follow recommendations but she still has questions.

“I don’t know the specifics of the threshold of not meeting the immune response they were hoping for. Was it close? Was it really far off?” Minkkinen asked. “I don’t think there will be harm in giving her an ineffective vaccine, if that’s what it becomes, at the end of the day. But why put her through three shots?”

The need to develop a vaccine for young children took on greater urgency with the rapid spread of the Omicron variant, which caused hospitalizations nationally to triple in January among children under 5.

Dr. Alpa Patel Shah, a pediatrician in Milwaukee, said that about a year ago she would diagnose COVID in a young child about every other week. Now, she might diagnose two or more in a day. Since the Omicron wave, she has had to refer at least two children under age 5 with serious symptoms to the hospital, where they were diagnosed with a dangerous inflammatory disorder called MIS-C that occurs about four weeks after a COVID infection.

Shah, who has a 2-year-old daughter, is among roughly 500 doctors who signed a letter to acting FDA Commissioner Janet Woodcock urging the agency to allow the youngest kids to begin receiving two Pfizer shots.

“Parents of children that are under the age of 5 and ineligible for vaccines have been living in a state of constant anxiety for about two years now,” Shah said. “It’s easy to say, ‘You’ve waited this long, what’s another month or two?’ But this is not a sustainable way to live.”

Dr. Kristin Moffitt, a pediatrician at Boston Children’s Hospital who specializes in infectious diseases, also supports vaccinating young children even if the doses aren’t fully protective, since the Pfizer trials identified no safety concerns.

“If they already have the data from the first two doses that shows the vaccine is safe and that there’s some degree of immunity afforded by two doses, then the only thing we’ll be waiting for in March is that a third dose is better,” Moffitt said.

Some experts, however, are worried about moving forward. Norman Baylor, president and chief executive of Biologics Consulting and the former director of the FDA’s vaccines office, said, “When I hear terms like ‘we hope the third dose is going to elicit’ a sufficient immune response,’’ he becomes worried. Regulators “can’t rely on hope,” he said, especially since poor protection could increase vaccine hesitancy in other age groups.

“How do you explain to the overall population of people who are hesitant that we are giving a vaccine to these children and the data may not be sufficient?” he said.

The intense, politically charged nature of the debate also influences parents’ thinking. Many parents are adamantly opposed to the vaccination, especially in young children. And one father who told the Globe he thinks the vaccines are unnecessary — because young children seemed to be at lesser risk from the virus and the vaccine hasn’t prevented breakthrough infections among recipients — asked to remain anonymous, fearing he would be considered an antivaxxer among his peers in Boston.

Katherine Monteiro and her daughter, Gia, 4, on the front steps of their home in North Andover. Monteiro is so eager to get her 4-year-old daughter vaccinated, she's willing to jump now. Jessica Rinaldi/Globe Staff

Many parents said the stakes involved in vaccination decisions feel much higher in young children, as they worry whether the injections could have so-far-undetected long-term effects on their developing bodies.

“I’m 35 so it was a no-brainer for me to get the shot,” said Medeiros, the Woburn mother of a 3-year-old and an 8-year-old. But after the vaccination, her menstrual cycle became more frequent, a correlation she finds worrisome

“I just would like to know, for these prepubescent children, is this going to cause any issues for them down the road?” she said.

If the vaccines were to lead to unknown long-term effects, she said, “I don’t want my decision to be the one that causes that.”

Moffitt noted that there is no biological reason for concern about an impact on fertility and that research shows women who are vaccinated are getting pregnant at the same rate as those who are not. The vaccine’s impact on menstrual cycles has been studied and appears to be a temporary shift from the stress of the immune response triggered by the vaccine — or the virus itself, which has triggered similar changes. More research is ongoing.

Some exhausted parents can’t bear the thought of studying more data or agonizing further over the risks to their children.

Eighth-grade teacher Melissa Aybar tried to read the evolving information on the vaccine and it “threw me back to April 2020 when I was obsessing over COVID numbers and data,” she said. “I am tired.”

Aybar, who lives in Dorchester, is reminding herself that her 2-year-old daughter has never reacted poorly to other vaccines, and that she is not inclined to second-guess them.

“I’ve landed on yes,” she said.