While the Centers for Disease Control and Prevention has recommended COVID booster shots for all adults, it is unclear when and if they will be needed for young kids.

Children aged 5 to 11 began getting inoculated with the Pfizer vaccine in late October, but the effectiveness of the shot on kids’ immune systems is still being determined by scientists, CNN reported.

Teens aged 16 and 17 may be eligible to get a booster dose soon as Pfizer requested that the Food and Drug Administration provide emergency use authorization of its shot for this age group last week.

Adults who received the Pfizer or Moderna vaccine are eligible to receive a booster dose six months after their second shot, and those who received the Johnson & Johnson vaccine are eligible to get a booster two months after their dose of the COVID vaccine.

Data showed that the COVID vaccine in adults waned in effectiveness over time, and a booster dose of the shot was necessary for immunity against COVID-19. But in younger kids, it has not been determined if immunity wanes with the vaccine and if a booster dose is necessary as data is still being collected by researchers. Answers are expected to become clearer sometime next year, according to CNN.

To determine if a booster dose is needed for kids, scientists will look for an increase in breakthrough infections in those children who are vaccinated.

Dr. Sean O'Leary, a professor of pediatric infectious disease at the University of Colorado School of Medicine, told CNN, “Probably most importantly, are we seeing any severe outcomes in children who've been previously vaccinated with two doses?”

Scientists believe that children may have a stronger immune system than older adults and may stay protected longer, which could push back the need for a booster dose, the news outlet said.

"Kids' immunity may last longer and that would mean they may be on a different schedule than the adults, that's if they need one at all,” Dr. Claudia Hoyen, director of pediatric infection control at UH Rainbow Babies and Children's Hospital in Cleveland, told CNN.

Safety is also key to whether young kids could be able to tolerate a third dose of the shot and whether it would be beneficial to provide another dose to this age group.

Dr. Claire Boogaard, the medical director of the COVID-19 vaccine program at Children's National in Washington, D.C., told CNN, “They don't want to stress a system that is already stressed to vaccinate another 2.3 million people if they don't need to.”

A minor is inoculated with the first dose of the Pfizer-BioNtech vaccine against the coronavirus A minor is inoculated with the first dose of the Pfizer-BioNTech vaccine against the coronavirus. Photo: AFP / Alfredo ESTRELLA