Experts advising the FDA recommended on Oct. 26 that the vaccine be permitted for children 5 to 11 years old, concluding that the benefits of the shot outweigh any risks.

The Pfizer-BioNTech shot has been authorized for people 16 years and older since December, and cleared for those 12 years and older since May. Here is what you need to know about Covid-19 vaccines and children:

When will children get the Pfizer Covid-19 vaccine?

More than 67% of people in the U.S. ages 12 and over are fully vaccinated against Covid-19, according to the Centers for Disease Control and Prevention. Some older people and people with compromised immune systems or otherwise at higher risk have begun to receive booster shots as well.

Vaccination among children ages 5 to 11 could start within a week if the CDC signs off and issues guidance on use of the vaccine in children next week.

The children will be given two shots three weeks apart, the same schedule as adults and adolescents, although each shot will contain one-third of the dosage.

Pfizer and BioNTech are studying their vaccine in children ages 6 months to under 5 years and have said results could come as soon as early 2022.

Do we need to vaccinate children?

Yes, according to most infectious-disease experts. Children can and do get sick from Covid-19, though research shows they typically experience milder cases and are much less likely than adults and the elderly to be hospitalized or die from the virus. Some hospitals across the country reported treating more children than ever this summer, which the CDC said reflected the rampant spread of the highly contagious Delta variant in much of the country.

In addition, scientists say children need to be vaccinated to achieve the communitywide, or herd, immunity that renders spread of the virus unlikely. “Vaccines give us the opportunity to really turn the tide on this pandemic, and children and teens really need to be a part of that strategy,” said Lisa Costello, a pediatrician and president of the West Virginia chapter of the American Academy of Pediatrics.

How effective is the vaccine?

Pfizer and its partner BioNTech released new data on Oct. 22 showing the vaccine was 90.7% effective at preventing symptomatic Covid-19 in a study of children age 5 to 11. The companies also said the vaccine was safe during the testing.

A review of the data by FDA staff found that the Covid-19 vaccine from Pfizer-BioNTech met the agency’s criteria for immune responses in the study of children age 5 to 11 years.

The companies’ vaccine—the only vaccine authorized for emergency use in children ages 12 to 15 and fully approved for anyone age 16 and over—has also proven to be effective in protecting those 12 years and older. The vaccine was 93% effective against hospitalization with Covid-19 among 12-to-18-year-olds, the CDC reported in October.

The Biden administration in October said it would make Covid-19 vaccines available to children age 5 to 11 at more than 25,000 pediatric offices and primary-care sites and at pharmacies and schools, should it be approved by federal regulators.

The Biden administration said it has procured enough doses of the Pfizer-BioNTech vaccine to inoculate the nation’s children. Pfizer was set to begin shipping doses on Oct. 30. Children could start getting inoculated after the CDC signs off.

Moderna Inc., which is also seeking authorization to widen the use of its shots to 12 years and older, has said its Covid-19 vaccine was generally safe and induced the desired immune responses in children ages 6 to 11 in a clinical trial.

Will vaccination be required for school?

The CDC urged all school staff and eligible students to get vaccinated ahead of the school year. Some universities required students to get vaccinated to return to campus this fall, and school districts including New York City have required teachers and staff to get the shots. Most school districts in the country already require students to have received vaccinations for mumps, measles and rubella, as well as polio, diphtheria and chickenpox, though many districts grant exemptions to students with pre-existing health problems or religious beliefs conflicting with the mandate. “If you’re in a district that has a lot of vaccine requirements already, I wouldn’t be surprised to see the Covid-19 vaccine just lumped in with those others,” said Noelle Ellerson Ng, associate director of advocacy and governance for AASA, the School Superintendents Association, a national umbrella group that represents school districts. Some districts might require Covid-19 vaccinations just for a year or two, until the pandemic dies down, some other school experts say.

What are children’s Covid-19 symptoms?

The symptoms are pretty much the same for children as they are for adults, according to the CDC. The symptoms include fever or chills, cough, loss of sense of taste or smell, and headaches. Doctors have also been probing links between Covid-19 and a rare inflammatory condition that causes stomach pain, skin rashes and a high fever. One reason why doctors and public-health experts say they hope children will get vaccinated is research indicating they can carry and transmit the virus even if they don’t show any symptoms.

Does the vaccine pose any risks to children?

Any vaccine comes with the risk of an adverse reaction, and the Covid-19 shots are no different, doctors and vaccine experts say. So far, however, researchers haven’t found evidence the vaccines pose any additional or different risks to children versus adults. The most common side effects to the vaccine, according to the CDC, are flulike symptoms such as fever, muscle aches and chills. Many recipients also experience arm soreness or bruising after receiving the shot.

In extremely rare cases, people who have received a Covid-19 vaccine have experienced severe allergic reactions, including anaphylaxis related to chemicals that help package the main ingredient in the Pfizer-BioNTech and Moderna vaccines, a compound known as mRNA.

Experts advising the CDC have said there appears to be an association between the mRNA vaccines and a rare inflammatory heart condition called myocarditis in some younger people, including young adults.

The CDC and other health authorities still recommend Covid-19 vaccination for those 12 years and older, given the greater risk from Covid-19, which itself can cause myocarditis and other complications.

The FDA flagged the risk of heart-inflammation conditions such as myocarditis in children age 5 to 11 years when it reviewed Pfizer-BioNTech data, but said the overall benefits in preventing Covid-19 disease and hospitalizations would outweigh the risk of the heart conditions.

No cases of myocarditis were found in the key study testing the Pfizer-BioNTech vaccine in 5- to 11-year-olds, though the study was considered too small to detect the potential risk.

Citing the risk of myocarditis, Norway has advised that all people under 18 years shouldn’t be given the Moderna vaccine, even if they had already received one dose, and recommended that men under 30 consider getting the Pfizer-BioNTech vaccine instead. Norwegian officials referred to U.S., Canadian and Nordic data, saying the absolute risks remain low and calling the advice a precautionary measure.

Studies indicate there aren’t safety risks for pregnant mothers or their unborn children from the vaccines, and that expectant mothers can pass on immunity-boosting antibodies to their fetuses after getting the shots. “Some parents will be skittish about the [Pfizer] vaccine because it is a new technology, but that just means there is a lot more educating to be done on the topic,” said Peter Hotez, a pediatrician and virology expert at Baylor University. “The safety profile looks about the same for children as it does for adults.”

—Sabrina Siddiqui contributed to this article.

 (This story has been published from a wire agency feed without modifications to the text)