Coronavirus Updates: C.D.C. Recommends 2 Covid Vaccines for Very Young Children

Subscribe to our newsletter

Image

Paxton Bowers, 5, receiving a Covid vaccination at Texas Children’s Hospital in November. Credit…Meridith Kohut for The New York Times

The Centers for Disease Control and Prevention on Saturday recommended Covid vaccines for children as young as 6 months, who were among the last Americans to qualify for the shots. Parents should be able to start getting young children immunized as soon as Tuesday.

Federal regulators now have authorized the Moderna vaccine for children ages 6 months through 5 years, and the Pfizer-BioNTech vaccine for children ages 6 months through 4 years. (Pfizer-BioNTech’s vaccine has been available to children ages 5 and older since November.)

All children 6 months and older, including those who have already been infected with the coronavirus, should get a Covid vaccine, Dr. Rochelle P. Walensky, the C.D.C.’s director, said in a statement.

“Together, with science leading the charge, we have takenanother important stepforwardin our nation’s fight against Covid-19,” she said. “We know millions of parents and caregivers are eager to get their young children vaccinated, and with today’s decision, they can.”   

Video

Dr. Rochelle P. Walensky, the director of the Centers for Disease Control and Prevention, endorsed the decision after a scientific panel backed the shots despite reservations about a paucity of data.CreditCredit… Centers For Disease Control And Prevention

Following meetings on Friday and Saturday, the agency’s scientific advisers strongly backed the vaccines, despite reservations about the paucity of data, especially regarding the efficacy of the Pfizer-BioNTech vaccine.

The C.D.C. panel heard evidence supporting the effectiveness of the vaccines in the youngest children, but repeatedly pressed Pfizer on its estimates and noted that three doses of that vaccine would be needed, compared with two doses of the Moderna vaccine.

Both vaccines are safe, and both produced antibody levels similar to those seen in young adults. But the C.D.C. advisers wrestled with the difficulty of recommending two very different vaccines for the same population.

“The implementation of these two rollouts is going to be incredibly challenging,” said Katelyn Jetelina, a public health expert and author of the widely read newsletter “Your Local Epidemiologist.”

“There’s going to have to be a lot of proactive communication about the difference between the two and the implications of taking one over the other,” she said.

In its clinical trials, Moderna found that two shots of its vaccine, each with one-fourth of the adult dose, produced antibody levels that were at least as high as those seen in young adults.

The company estimated the vaccine’s efficacy against symptomatic infection at about 51 percent among children ages 6 to 24 months, and 37 percent among children ages 2 through 5.

The side effects were minor, although about one in five children experienced fevers. Efficacy against severe disease and death is assumed to be higher, similar to the effects seen in adults.

Based on those data, the F.D.A. authorized two shots of the Moderna vaccine, spaced four weeks apart.

The Pfizer-BioNTech vaccine also produced a strong immune response, but only after three doses, company officials told the scientific advisers on Friday.

Two doses of the vaccine were inadequate, they said — justifying the F.D.A.’s decision in February to delay authorizing the vaccine until regulators had data regarding three doses. Two doses may not have been enough because the company gave the children just one-tenth of the adult dose in each shot, some advisers said.

The vaccine has an overall efficacy of 80 percent in children under 5, Pfizer’s scientists claimed on Friday. But that calculation was based on just three children in the vaccine group and seven who received a placebo, making it an unreliable metric, the C.D.C.’s advisers noted.

“We should just assume we don’t have efficacy data,” said Dr. Sarah Long, an infectious diseases expert at Drexel University College of Medicine. But Dr. Long said she was “comfortable enough” with other data supporting the vaccine’s potency.

Three doses of the Pfizer vaccine produced antibody levels comparable to those seen in young adults, suggesting that it is likely to be just as effective.

“The Pfizer is a three-dose series, but as a three-dose series, it’s quite effective,” said Dr. William Towner, who led vaccine trials for both Moderna and Pfizer at Kaiser Permanente in Southern California.

Either vaccine would be better than none, Dr. Towner added. He predicted that some parents may opt for Moderna because bringing children to a pediatrician for two shots is easier than arranging for them to receive three.

The Pfizer vaccine was authorized for children 5 to 11 in November, but fewer than 30 percent in that age group have received two shots. In surveys conducted by the C.D.C., about half of parents said in February that they would vaccinate their children, but by May, only one-third of parents said they intended to do so.

The advisers debated whether vaccination enhances protection against severe disease in children who have already been infected. There is little information available from children aged 5 to 11, because of the poor uptake of vaccines in that age group.

But in adults, an infection with the earlier Omicron variant has not been enough on its own to protect from the newer versions.

Vaccinations would still be needed to protect children from future variants, the experts concluded. “That combined protection is really the safest and the most effective,” said Dr. Sara Oliver, a C.D.C. scientist who led the discussion on Saturday.

Parents of the youngest children may be more willing to opt for a Covid vaccine if it can be offered alongside other routine immunizations, Dr. Towner said.

“That’s the area that a lot of people are not sure of right now,” he said. “I’m hoping there’ll be some guidance offered around that.”

Image

The C.D.C. advisory panel raised concerns about the Pfizer-BioNTech vaccine bottles needing to have their labels updated to reflect the new rules.Credit…Saul Martinez for The New York Times

With the Centers for Disease Control and Prevention formally recommending Moderna and Pfizer-BioNTech vaccines for children as young as 6 months old, parents across America should be able to start getting their youngest children immunizations by Tuesday.

All children 6 months and older, including those who have already been infected with the coronavirus, should get a Covid vaccine, Dr. Rochelle P. Walensky, the C.D.C.’s director, said in a statement on Saturday.

On Friday, the Food and Drug Administration authorized the Moderna and Pfizer-BioNTech vaccines for very young children.

Scientific advisers to the C.D.C. unanimously voted to recommend Moderna and Pfizer-BioNTech vaccines after three and a half hours of discussion on Saturday.

Here are four key takeaways from that meeting.

Experts at the meeting considered that over two million children of ages 6 months to 4 years had been infected, 20,000 had been hospitalized and 200 had died from the virus — and many of those experts explained that the benefits of vaccinating young children outweighed possible risks.

Several experts said that, although we did not know what kind of variants we could expect in the future, the vaccinations would save lives.

“This is an opportunity that one does not get very often: the prevention of children’s deaths. We know this disease is killing children,” said Dr. Beth Bell, a member of the C.D.C.’s Advisory Committee on Immunization Practices. “And we can help prevent those deaths through this vaccine.”

Concerns were raised about incorrect labeling on packaging for the Pfizer-BioNTech vaccine. The label states that the vaccine can be given to children between the ages of 2 and 5 years old, but the C.D.C. has now approved the vaccine for children between the ages of 6 months and 4 years. (The Pfizer-BioNTech vaccine had already been approved for children ages 5 to 11 years old.)

The more reliable indicator that the vaccine is approved for children as young as 6 months is its maroon cap. The vaccine for children between 5 and 11 years old has an orange cap.

Additionally, the label states that the vaccine can be stored only for six hours after dilution, but this is also incorrect, according to the C.D.C. The vaccine can be stored for up to 12 hours after adding saline to generate 10 doses.

Pharmacists and doctors have been trained to never waste a single dose of any vaccine. With the pandemic, and the early scarcity of vaccines, wasting vaccines became even more unthinkable. However, getting as many of the youngest Americans vaccinated as possible may turn that notion on its head.

The vaccine vials have 10 doses. Once a vial is opened, it must be used within 12 hours, after which it has to be discarded. Providers will be encouraged to vaccinate children even if it means using only one or two doses from a vial.

Providers may have been averse to wasting vaccines in the past, but they should not “feel guilty about having to open a vial to administer two doses or one dose,” said Dr. José R. Romero, the newly appointed director of the National Center for Immunization and Respiratory Diseases. “It’s important to get shots into arms and take advantage of every opportunity.”

Immunocompromised people are generally given an extra dose of vaccine for their primary series. The Pfizer-BioNTech vaccine for young children requires three doses, and the Moderna vaccine requires two doses — but it remains unclear whether immunocompromised young children should get three doses of either vaccine or four of Pfizer and three of Moderna.

Some at the meeting believed that there simply was not enough data on young children who are immunocompromised to make these assessments. Detailed guidelines about vaccinating immunocompromised children are expected to be issued later.

Maham Javaid

Image

Akilah Edwards and her daughter Ayva, 2, at a Juneteenth celebration in Middletown, Ohio, on Friday. Ms. Edwards said she did not plan to have her children vaccinated.Credit…Maddie McGarvey for The New York Times

For many parents across the United States, the long-awaited news that young children would soon become eligible for a coronavirus vaccine was met with a rush of relief.

“I just got goose bumps!” Brendan Kennealy, a father of two daughters, ages 1 and 4, in Richfield, Minn., said on Friday. He added that he would take his girls in for shots promptly, once he spoke to their pediatrician.

For many others, the development came with deep reservations. “I feel like it’s way too soon,” said Megan O’Donnell of York, Pa., who was visiting the Maryland Science Center in Baltimore with her husband and three children, ages 8, 3 and 1. She said she worried about the effect the vaccine would have on her youngest.

The Food and Drug Administration authorized the Moderna and Pfizer-BioNTech vaccines for young children on Friday, clearing a key hurdle for the 20 million children under 5 in the United States who have not yet been eligible to be vaccinated.

A panel of experts advising The Centers for Disease Control and Prevention granted its endorsement on Saturday afternoon, and the director of the agency approved final guidance for their use later in the day, paving the way for vaccinations to begin next week.

But reluctance about the vaccine for young children persists nationwide, particularly among parents who are themselves unvaccinated.

In Middletown, Ohio, Akilah Edwards was enjoying an outdoor Juneteenth celebration with her children, Jakari, 1, and Ayva, 2. She said the festival came at the end of a long period of staying indoors and away from people for fear of Covid.

“They haven’t experienced the park before,” Ms. Edwards said as her children enthusiastically took in the music and festivities. But she said she would not be vaccinating her children any time soon.

“I’m not ready for that. I’d have to get it myself first,” she said, adding that she was still uncomfortable with the vaccine. “I am glad they are doing it, but it’s scary,” she said.

Lindsey Douglas, a pediatrician and the medical director of quality and safety for the Mount Sinai Kravis Children’s Hospital in Manhattan, said that she would “wholeheartedly recommend” the vaccine for all eligible children.

But many parents have doubts about the vaccine’s effectiveness in young children.

Image

Teng Weng with his daughters Charlene, 3, and Katreeya, 6, in Woodbury, Minn. He said expert authorization of the vaccines gave him “a little confidence, but not 100 percent.”Credit…Jenn Ackerman for The New York Times

At an indoor playground in Woodbury, Minn., Teng Weng voiced concerns about vaccinating his two daughters, ages 3 and 6. The F.D.A. authorization of the vaccines gave him “a little confidence, but not 100 percent,” he said.

Pediatricians and public health officials are preparing for an uphill climb in persuading parents about the benefits of the vaccines.

Though Pfizer’s vaccine has been available to children 5 to 11 years old since last fall, less than 30 percent of children in that age group are fully vaccinated.

“I remain concerned that there has been really a low number of children between the ages of 5 and 11, and even the 12- to 16-year-olds that could get the Pfizer vaccine,” said Donna Hallas, director of the pediatric nurse practitioner program at N.Y.U. Rory Meyers College of Nursing.

Image

Edna N. Luckett of Oxford, Miss., said that she is hesitant to have her daughter, Faith Gipson, 3, vaccinated against Covid-19 if the vaccine is cleared for children under 5. She has waited to have her two older children vaccinated, too.Credit…Timothy Ivy for The New York Times

In Oxford, Miss., Edna N. Luckett watched her two youngest children play at a library and said that talking with their pediatrician about the vaccines had helped her understand the choices available to her.

Still, she said she had no immediate plans to vaccinate her children, ages 10, 6 and 3. “It’s just the fear of the unknown,” she said. “We don’t know a lot about it. And especially in the Black community, we don’t have a good history of being heard by health care officials.”

For other parents, though, the prospect of a vaccine could not have arrived soon enough. Outside the National Aquarium in Baltimore, Kasey Gillette of Washington, D.C., said that Covid-19 arrived when her daughter, now 2, was an infant. Concerned that the lack of interaction was stunting her daughter’s social skills, Ms. Gillette decided last summer to send her to day care. But she has worried that her daughter will pick up the virus there or that, as Ms. Gillette returns to the office, she will bring it home.

Still, she said, she was ready to start opening their lives to the world again. “It just feels like we’ve been home for three years. Or is it two years? Ten years?” she said.

“Feels longer.”

Eliza Fawcett, Kimiko de Freytas-TamuraChristina Capecchi, Ellen B. Meacham, Kevin Williams and Adam Bednar

Image

A boy receives his first dose of the Pfizer-BioNTech vaccine last year.Credit…Emily Elconin for The New York Times

Understandably, many parents of young children have questions about the new coronavirus vaccines for babies and toddlers and the expected rollout soon of the Pfizer-BioNTech and Moderna shots. We talked with infectious disease pediatricians to get answers to the most common ones.

One specific question came from parents with 4-year-olds, particularly those who are just about to turn 5. Since a two-dose Pfizer vaccine has been available for children between 5 and 11 since last fall, they want to know if it makes sense to wait until their children turn 5 so they can get the more potent version of Pfizer. The Pfizer shots for children younger than 5 would be administered in three doses, which contain three micrograms while those for older children contain 10.

All the experts said not to wait, recommending that parents of 4-year-olds start the vaccination process as soon as possible, even if that would mean beginning with the lower dose version.

“The sooner you start them off getting protection, the better,” said Dr. Yvonne Maldonado, a pediatric infectious disease physician at Stanford Medicine who chairs the American Academy of Pediatrics’ committee on infectious diseases.

If your child turns 5 before a second or third dose of the Pfizer vaccine, they would likely get bumped up to receive the higher dose for the rest of the series, said Dr. Debbie-Ann Shirley, a pediatric infectious disease physician at the University of Virginia, as this is what the A.A.P. recommends for older children who transition into a new age group while receiving Covid-19 vaccines.

So, what about parents of 4-year-olds who are bigger than the average 5- or even 6-year-olds? As Christina Caron reported when the vaccine for school-age children was cleared, it does not matter whether a child is smaller or larger than other children their age when it comes to vaccines.

Weight is an important factor when you give a young child medication like Tylenol because there is a wide variation in weight from infancy throughout childhood and too much of the drug could be toxic.

The optimal vaccine dose, however, is dependent on age and tailored to minimize potential side effects.

Parents with 4-year-olds do have another option, though. Moderna’s vaccine for little kids, which is for children 6 months through 5 years old, would be administered in two doses at a lower dosage than adults. The Centers for Disease Control and Prevention has not yet weighed in on Moderna’s vaccine for children ages 6 to 17.

Asked to compare the Moderna and Pfizer vaccines for very young children at a press briefing on Friday, Dr. Peter Marks, who leads the F.D.A.’s vaccine division, said that Moderna’s vaccine might trigger an immune response “slightly more rapidly,” while Pfizer’s might “bring a greater response after the third dose.” He said parents should feel comfortable with either, and he recommended they go with whichever one is available.

Sharon LaFraniere contributed reporting.

Image

A family enters a pop-up Covid-19 vaccine site in Queens last June. New York City is preparing to distribute vaccine for children younger than 5.Credit…Scott Heins/Getty Images

Health officials in New York City are preparing to distribute vaccines for children younger than 5 starting on Wednesday, according to a new plan announced on Friday by Mayor Eric Adams.

The plan, which was contingent on the federal action that came on Saturday with the endorsement of Pfizer-BioNTech and Moderna vaccines for very young children, would rely on pediatrician offices and 10 city vaccine hubs to offer the vaccine.

“I know how long parents and caretakers of our little ones have been waiting for the moment their youngest would have access to a Covid-19 vaccine, and as soon as that moment comes, I want them to know we will be ready,” Mr. Adams said in a statement.

Starting on Tuesday, parents can use the city’s “Vaccine Finder” website to schedule an appointment at several kinds of locations. Clinics that have been serving children 5 and older will shift to vaccinating younger children, the mayor’s office said. Ten vaccine hubs, including sites in Times Square, the Queens Center Mall and the Brooklyn Children’s Museum, will offer the Moderna vaccine for young children. The Pfizer vaccine will also be available at other locations.

Moderna’s two-dose vaccine is for children 6 months through 5 years old, while Pfizer’s three-dose vaccine is for children 6 months through 4 years old.

Health officials encouraged parents to reach out to their child’s doctor to ask if they will have the vaccines. The city’s health department has been conducting “educational outreach” to pediatrician offices and said that some families might feel more comfortable getting the vaccine from a trusted provider.

On Saturday, the vaccines received federal clearance by the Centers for Disease Control and Prevention, whose advisory panel endorsed the vaccines and whose director then signed off on the recommendation. On Friday, the Food and Drug Administration authorized the Pfizer and Moderna vaccines for very young children.

More than 88 percent of adults in New York City are fully vaccinated, but only about 60 percent of children ages 5 to 17 are fully vaccinated, according to city data. Vaccination rates for children are highest in Manhattan — about 92 percent of children have received one dose — and lowest on Staten Island, where only 54 percent of children have received one dose.

The city’s health commissioner, Dr. Ashwin Vasan, said in a statement that the vaccines for children under 5 were safe and protected against the virus and severe complications.

“As the city’s doctor, and as a father of a 3-year-old, I have confidence in this vaccine, and I can’t wait to get my child vaccinated,” he said.

Image

A mobile pediatric clinic in Miami on Friday. Credit…Saul Martinez for The New York Times

Facing withering pressure from medical professionals and the federal government, Florida began to allow pediatricians, children’s hospitals and other physicians on Friday to order coronavirus vaccines for the youngest children, according to state and White House officials. The shift would ensure that families would be able to get the shots at doctors’ offices, though later than in every other state in the country.

The White House praised the move as an important first step, calling it a “reversal” by Gov. Ron DeSantis, a Republican with presidential ambitions who frequently casts himself as a foil to President Biden. Mr. DeSantis’s administration insisted that it had not budged from its original position and only allowed orders once the Food and Drug Administration authorized the Moderna and Pfizer-BioNTech vaccines for very young children on Friday morning. A panel of experts advising the Centers for Disease Control and Prevention granted its endorsement on Saturday, and the agency’s director then backed the recommendation, officially clearing the way for vaccinations to begin next week.

Unlike the other 49 states and the District of Columbia, Florida did not allow health care providers to preorder the vaccines ahead of the federal government’s June 14 deadline. As a result, no doses will be sent to doctors’ offices in the state during the first wave of vaccine shipments, scheduled to arrive starting on Monday. The second wave of preordered doses, which Florida also missed, is scheduled to arrive about a week later.

“The state of Florida intentionally missed multiple deadlines to order vaccines to protect its youngest kids,” Dr. Ashish K. Jha, the White House’s coronavirus response coordinator, told reporters on Friday.

In a statement, Bryan Griffin, a deputy press secretary for Mr. DeSantis, said characterizing Florida’s policy as a reversal was “patently false.”

“We have always maintained the position that the state of Florida has chosen not to be involved in the preordering or distribution of the vaccine for children under 5,” he said. “The state of Florida does not recommend the vaccine be administered to healthy children,” he added, referring to guidance the state issued in March against the advice of the C.D.C.

State officials had said on Thursday that doctors could order vaccines as needed. But doing so requires using a state portal that was not opened for those orders until Friday.

Dr. Lisa Gwynn, the president of the Florida chapter of the American Academy of Pediatrics and an associate professor at the University of Miami, said she was in contact with the Florida Department of Health about the vaccines last week and was not informed that no preorders would be placed and physicians would be allowed to place orders only after the shots received F.D.A. authorization.

“I’ve been back and forth, in touch with the people in the agency,” she said. “They’re not telling me this.”

In a statement after the publication of this article, Mr. Griffin noted that it has always been state policy to allow vaccine orders on the portal after F.D.A. authorization.

Vaccinations for very young children are typically administered at pediatricians’ offices, but unlike pharmacies in the federal Covid vaccine program, doctors cannot order doses on their own, Dr. Gwynn said. She added that it seemed that some Florida officials were suggesting on Thursday that doctors order vaccines directly from the federal government, before the state opened its online portal.

“First they said providers could order directly from the federal government,” she noted. “That’s not true. We have to order through the state.”

On Thursday, Mr. DeSantis defended his administration’s refusal to preorder any vaccines for state-run medical facilities. That includes county-level public health offices, which are under state control.

“I would say we are affirmatively against the Covid vaccine for young kids,” he said. “These are the people who have zero risk of getting anything.”

By Friday morning, a congressional subcommittee overseeing the coronavirus response had sent Mr. DeSantis a letter urging him to reverse his position. Mr. Griffin said that letter had no bearing on the administration’s policy.

Noah Weiland contributed reporting.

Image

A sign informing people about Covid-19 vaccines at a local pharmacy in Miami on Friday.Credit…Saul Martinez for The New York Times

For Jacqueline Almeida, next week cannot come soon enough.

She has watched friends roll their eyes when she asked to meet them outdoors. She has tried unsuccessfully to convince her sister to vaccinate her son. She was told by strangers on Twitter that putting her daughter in a mask was tantamount to child abuse.

And yet the vaccines for the youngest Americans faced delay after delay. “It was very disappointing, month after month, seeing everything get pushed,” said Ms. Almeida, 33, who lives in Franklin, Tenn.

In a letter to officials at the Food and Drug Administration in April, nearly 70 scientists offered their own assessment: The delay was preventable. Their argument is a technical one, but with broad implications.

The agency and the manufacturers chose to evaluate the vaccines by tracking blood levels of antibodies, the scientists said. But had regulators also considered other parts of the immune system, it might have been clear early on that the vaccines could prevent serious illness, if not infection, in young children.

In particular, the scientists argued, the vaccine manufacturers should have been measuring so-called T cells, which can kill infected cells and rid the body of the virus. That “would have allowed us to possibly make a different decision about allowing a vaccine to move forward earlier,” said John Wherry, director of the Institute for Immunology at the University of Pennsylvania and one of the letter’s signatories.

Vaccine manufacturers ran large trials to measure the efficacy of the vaccines at preventing symptomatic infection in adults. But in the children’s trials, the investigators looked at blood levels of antibodies following vaccination, comparing them with the levels seen in young adults.

The F.D.A. used this method, called immunobridging, to authorize the Pfizer-BioNTech vaccine for children aged 5 to 11 and for adolescents aged 12 to 15. But in December, the companies reported that two doses of their vaccine did not produce high antibody levels in children aged 2 through 4.

The companies decided to assess whether a third dose improved the vaccine’s performance. Then, over the winter, some young children in the clinical trial became infected with the Omicron variant.

Based on preliminary data from those infections, the F.D.A. said it would consider authorizing two doses of the vaccine while the companies continued to test the third — a decision that provoked mixed reactions from parents and experts.

But the number of infections among children grew, and the accruing data did not support the F.D.A.’s decision, prompting the agency to cancel its planned review. The back-and-forth left parents confused and their children vulnerable, as Omicron variants rampaged through the nation.

More information about T-cell immunity generated by the vaccines might have delivered the shots to desperate parents sooner and prevented at least some of those hospitalizations, experts said in interviews.

Antibodies are essential for neutralizing the virus on entry and preventing infection, and they can easily be measured in just a drop or two of blood. But while there are dozens of rapid tests for antibody levels, assessing T cells requires at least a few milliliters of blood and at least a day to test just a few samples.

Including T cells in a vaccine analysis would “really up the complexity and cost of the study,” said Dr. Camille Kotton, an infectious disease physician at Massachusetts General Hospital and a scientific adviser to the C.D.C.

“It’s never as easy as antibodies, but it definitely would be helpful,” she said.

Image

Vaccines from Pfizer and its partner BioNTech have already been available for Americans 6 and older, and Moderna’s vaccines for adults.Credit…Allison Zaucha for The New York Times

Federal health officials on Saturday cleared the Moderna and Pfizer-BioNTech coronavirus vaccines for very young children —  the only age group in the United States that does not yet have a vaccine option available.

Doses could be rolled out as soon as Tuesday. Vaccinating the youngest children would provide relief for many families who have had to deal with disruptions to day care and preschool during the pandemic, as well as worries that their children might be among the few who become seriously ill with Covid-19.

Vaccines from Pfizer and its partner BioNTech have already been available for Americans 6 and older, and Moderna’s vaccines for adults.

On Friday, Dr. Peter Marks, who heads the Food and Drug Administration’s vaccine division, said that parents should feel comfortable vaccinating their very young children with either the Pfizer-BioNTech or the Moderna vaccine, whichever one was available.

Here are some key facts about the pediatric vaccines.

  • Age range: Six months through 4 years old.

  • Number of shots: Three.

  • Spacing of shots: Three weeks between the first and second shots, and at least eight weeks between the second and third.

  • Dosage: Three micrograms in each shot. For comparison, children 5 to 11 years old are given two 10-microgram shots; adolescents and adults get two 30-microgram shots.

  • Efficacy: Pfizer’s scientists say the vaccine has an overall efficacy of 80 percent in children under 5, but that calculation was based on an extremely small sample of 10 children.

  • Age range: Six months through 5 years old.

  • Number of shots: Two.

  • Spacing of shots: Four weeks apart.

  • Dosage: Twenty-five micrograms in each shot — one-fourth the size of the shots for adults.

  • Efficacy: Moderna estimated the vaccine’s efficacy against symptomatic infection at about 51 percent among children ages 6 to 24 months, and 37 percent among children ages 2 through 5.

Correction: 

June 21, 2022

Because of an editing error, an earlier version of this article misstated the comparison between child and adult doses of the Moderna vaccine. The youngest children will get a dose of 25 micrograms per shot — one-fourth the size of the shot for an adult. Also because of an editing error, the article misstated the dosage of the Pfizer-BioNTech vaccine for children 5 to 11 years old. They are given two 10-microgram shots, not two 20-microgram shots.

Carly Olson and Johnny Diaz

Read More