Kids vaccine Wren Nagata, 7, with his sister 5-year-old Mallory Nagata, of Pasadena
Wren Nagata, 7, with his sister 5-year-old Mallory Nagata, of Pasadena, show off their bandaids after receiving their COVID-19 vaccines during an event kicking off coronavirus vaccinations for children age 5-11 at Eugene A. Obregon Park in Los Angeles on Wednesday, Nov. 3, 2021. Image Credit: AP


  • Overwhelming data from clinical trials show the vaccines work and are safe for children.
  • Researchers predict a global ramp up of vaccinations would have huge implications for the global COVID fight.
  • Countries like the UAE and China have approved COVID shots for children.

Immunisation of children against COVID-19 is getting ramped up globally. This follows the approval of COVID-19 vaccines for children, which means million of kids getting inoculated.

The Pfizer-BioNTech vaccine, which has shown 90.7% efficacy in children aged five to 11, was greenlighted recently by US health authorities. Earlier, countries like the UAE and China, had already approved COVID-19 shots for children from as young as age 3.

For context, let's backtrack: COVID-19, the disease caused by the coronavirus, has reportedly killed more than 5 million people worldwide, though the real count may actually be higher, say experts, who also believe the disease burden, too, could be much worse than reported.

And since July, cases among children of COVID-19 reportedly rose (240% in the US alone). Globally, there are 1.5 billion school-age kids affected by school closures.

Late on Tuesday, the Centers for Disease Control and Prevention (CDC) gave the greelight for children ages 5 to 11 to get kid-size doses of the Pfizer shot. Paediatricians and other doctors’ groups lauded the CDC's move. Paediatric vaccinations started right away in the US. Your key questions answered:

How many children were enrolled in the COVID-19 paediatric vaccine trial and in which countries?

The Pfizer-BioNTech vaccine trial enrolled up to 4,650 children ages 6 months to 11 years of age in the following countries:

  • United States
  • Finland
  • Poland
  • Spain

There were more than 90 clinical trial sites in those four countries. Of that number, nearly two-thirds received vaccine; the others received a placebo. The kids received two doses, three weeks apart.

What was the end point of the trial?

It was designed to evaluate the safety, tolerability, and immunogenicity of the Pfizer-BioNTech vaccine on a two-dose schedule (approximately 21 days apart) in three age groups:

  • ages 5 to 11 years
  • ages 2 to 5 years
  • ages 6 months to 2 years

What’s the dose of the vaccine administered?

The trial (Phase 2/3 study) enrolled children with or without prior evidence of SARS-CoV-2 infection.

  • Children ages 5 to 11 years: two-doses of 10 µg (vs. 30-µg dose used for people 12 and older)
  • Children under age 5 received a 3 µg dose for each injection.

The two-dose regimen were administered 21 days apart.

1 microgram (represented by the symbol µ) is one millionth of a gram.

What were the trial results?

Two important results came out of the trial:

  • 1. There was favourable safety profile (i.e. that it is safe), for the children tested.
  • 2. There was a "robust" neutralising antibody responses in children 5 to 11 years of age.

According to the Pfizer filing evaluated by US drug regulators, the antibody responses in the participants (5- to 11-year olds) given 10-µg doses were comparable to those recorded in a previous Pfizer-BioNTech study in people 16 to 25 years of age immunised with 30 µg doses.

The 10 µg dose was decided upon as the preferred dose for safety, tolerability and immunogenicity in children in the target age group.


Number of children enrolled in the Pfizer paediatric vaccine trial, ages 6 months to 11 years of age across 90 sites in 4 countries.

What is the implication of paediatric COVID vaccines in global counter-pandemic efforts?

Experts say the impact would be huge. “It will save lives in that age group,” Emma McBryde, an infectious-diseases modeller at the Australian Institute of Tropical Health and Medicine in Townsville, told Nature. “For every child’s life you save, you may well save many, many more adult lives,” she says.

There’s also an anticipated broader impact: Children account for a significant portion of new COVID-19 cases, and they're also capable of transmitting the coronavirus SARS-CoV-2 to others.

Other countries, have earlier approved non-mRNA COVID-19 vaccines in young children, including the UAE. On August 2, 2021, the UAE approved the use of Sinopharm vaccine for children aged between 3 and 17 years, following the results of clinical studies. Children have signed up with full parental consent. On June 5, 2021, China approved a COVID-19 vaccine for children as young as three.

What about side effects?

mRNA-based vaccines have been linked to a very small risk of myocarditis, an inflammation of the heart muscle, and pericarditis, an inflammation of the lining around the heart; as well as pericarditis, an inflammation of the lining around the heart, particularly in young men.

No reports of either condition were found among the children ages 6 months to 11 year olds in the trial conducted in the four Pfizer trial countries mentioned above. It's a good sign, Andrew Pavia, chief of the division of paediatric infectious diseases at University of Utah told Nature. COVID-19 infection is known to kill children, too, though to a lesser extent than adults, especially those with so-called comorbidities.

to Andrew Pavia, chief of the division of paediatric infectious diseases at University of Utah told Nature.

91 %

efficacy of the Pfizer–BioNTech vaccine in preventing symptomatic SARS-CoV-2 infection in 5- to 11-year olds based on trial involving 4,650 children in four countries.

As the shots are distributed to a larger population, regulators would continue to watch for any sign of the side effects.

What about rare problems?

Tens of millions of the larger doses have been given safely to Americans 12 and older. One very rare serious side effect has come to light: heart inflammation. These rare reactions have occurred mostly in young men or teens boys, usually after the second dose, and they tend to recover quickly.

To put the risk in context, doctors say COVID-19 infection can cause more serious heart inflammation. One theory is that testosterone and puberty play a role, which is partly why experts expect any risk to younger kids would be even lower.

Should elementary school-aged children get vaccinated?

Yes, according to US health authorities and leading doctors’ groups. Even though the virus tends to be more severe in adults than children, COVID-19 is causing plenty of preventable suffering among youngsters. About 1.9 million kids ages 5 to 11 have been diagnosed with COVID-19. Some 8,300 have been hospitalised, about a third needed intensive care, and at least 94 deaths have been verified.

That’s not counting the risk of a serious complication called multisystem inflammatory syndrome that can hit kids several weeks after they recovered from even a mild infection. Vaccination also promises to help kids more safely resume school and social activities.

Are kid doses the same size as adult ones?

No. Children ages 5 to 11 will receive a third of the dose given to teens and adults. That’s 10 micrograms per shot for youngsters, compared to 30 micrograms per shot for everyone 12 and older. Like everybody else, the younger kids will get two shots, three weeks apart.

How well do the shots work?

In a study, Pfizer’s pediatric vaccine proved nearly 91% effective at preventing symptomatic infection. Vaccinated youngsters developed levels of virus-fighting antibodies as strong as teens and young adults who’d received the full-strength dose.

Where are the shots available?

The shots are being offered at pediatricians’ offices, health clinics and pharmacies. Some school systems also plan to host vaccination clinics, too. Two drugstore chains will start giving the shots this weekend: Walgreens on Saturday and CVS on Sunday.

Can my child get a flu shot at the same time?

Yes, the CDC says COVID-19 shots can be given at the same visit as vaccines for the flu, or other routine vaccinations a child — or anyone else — may require.

What if my child is about to turn 12?

CDC said children should get the dose that’s right for their age on the day of vaccination. So if a child gets the 10-microgram dose for the first shot and then turns 12, the second shot should be the 30-microgram dose.

Should I just wait until their 12th birthday so both shots are the bigger dose?

Pediatricians advise not to postpone vaccination because the kid-size dose is effective in that age group.

Is the CDC’s move a mandate?

No. The CDC has not mandated COVID-19 vaccinations for youngsters, but recommended them.

However, most schools in the US already mandate vaccines for other infectious diseases. Vaccine mandates have a long history in the US where, as early as the 19th century, some states already required immunisation in schools. One simple goal of the mandates is to stop the spread of potentially deadly diseases; another is to prevent outbreaks from disrupting the classroom as kids get sick and stay home.

Research on other infectious diseases suggests that mandates successfully increase vaccination rates among children. More than 80% of kids in the US are inoculated for other diseases — including polio, measles, and chickenpox, by age 2 — so serious outbreaks are very rare and almost never disrupt schools.

Aren’t only some kids at high risk of serious COVID-19?

Nearly 70% of 5- to 11-year-olds hospitalised for COVID-19 have had other medical problems, including obesity and asthma. But sometimes the otherwise healthy get seriously ill, too. And due to the profound social, mental health and educational impact the pandemic has had on youngsters, health authorities made clear that all children should be vaccinated. 

What if my child already had COVID-19?

The CDC recommends they still should be vaccinated once they’ve recovered. It’s clear that prior infection does provide some protection against another bout — but that immunity can vary depending on how seriously ill someone was, and how long ago. Studies of adults have found that vaccination after infection can dramatically boost protection.

kids vaccine 5-11 year olds
Image Credit: AP

Is Pfizer’s vaccine the only choice for children?

In the US, for now, it is. A silimar vaccine from Moderna vaccine is used by teens in some other countries and is being tested in younger children. It's not yet approved for Americans under age 18.

Other countries, have earlier approved non-mRNA COVID-19 vaccines in young children, including the UAE. On June 5, 2021, China approved a COVID-19 vaccine for children as young as three. On August 2, 2021, the UAE approved the use of Sinopharm vaccine for children aged between 3 and 17 years, following the results of clinical studies. The move came after an extensive evaluation process that led to emergency-use approval of the vaccine for the young ones and the local evaluation that complies with the country’s health regulations. Children have signed up with full parental consent.

What about vaccinations for children younger than 5?

As for Pfizer and Moderna, both are testing low doses in babies and preschoolers.

Evaluation of COVID vaccines for infants and toddlers is now moving forward. Dr Inci Yildirim, associate professor of paediatrics (infectious diseases) at Yale School of Medicine, is leading Yale’s component of Moderna’s clinical trial of a vaccine for children 6 months to 12 years of age. Yildirim said vaccinating young children could protect their own health more than people assumed when the pandemic began.

(With inputs from Associated Press)