High-risk adults have been eligible for the COVID vaccine in the U.S. since December, and in the five months since, eligibility across the country has continued to expand until the vaccine became available to everyone over the age of 16 in April. Now we just got one step closer to fully vaccinating the U.S.: Kids ages 12 to 15 are finally able to get their shots after both the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA) agreed the Pfizer vaccine is safe and effective for this younger age group. On Thursday, May 13, some states started administering shots to 12 to 15 year olds. But as many adults know, the protection of the vaccine can come with a side effect or two, and research shows it's no different for kids. In fact, there's may come on even stronger.
The FDA based its decision to grant emergency use authorization of the Pfizer vaccine for adolescents ages 12 to 15 on data from the manufacturer's Phase 3 clinical trial, according to a statement from Pfizer on May 10. The trial enrolled nearly 2,300 participants and gave insight into what vaccine side effects are most prominent in kids ages 12 to 15.
According to the clinical trial's findings, 77.5 percent of adolescents ages 12 to 15 experienced fatigue after getting the Pfizer vaccine, which is higher than the percentage of participants 16 years and older who reported feeling fatigue after getting the Pfizer shot. In earlier clinical trials on adults and older teens, 62.9 percent felt fatigue as a result of the Pfizer vaccine.
While fatigue was the most common systemic reaction among kids—meaning a response that affects the entire body—the most common side effect overall was pain at the injection site, which 90.5 percent of 12 to 15 year olds experienced. As was the case with fatigue, the side effect was also more common among the younger age group; in Pfizer's clinical trials on adults, 84.1 percent of participants had pain at the injection site after their shot.
Children also experienced some other side effects more frequently than adults did. According to the data, 75.5 percent of kids reported having a headache versus 55.1 percent of adults; 49.2 percent of kids experienced chills compared to 31.9 percent of adults; 42.2 percent of kids had muscle pain, which 38.3 percent of adults reported feeling; 24.3 percent of kids had a fever versus 14.2 percent of adults; and 0.8 percent of kids had swollen lymph nodes in comparison to the 0.3 percent of adults who had that rare reaction.
However, there were other side effects that adults were more likely to experience, but by smaller margins: 10.5 percent of adults had swelling at the injection site, while 9.2 percent of kids had the same response; 9.5 percent of adults had redness at the injection site versus 8.6 percent of kids; and a mere 1.1 percent of adults experienced nausea, which only 0.4 percent of kids also reported.
But much like with adults, these side effects in kids are expected and are not any reason to be concerned. The FDA issued a statement on May 10 that said that adolescent side effects were consistent with those reported by adults and that they should typically only last one to three days.
"The sore arms and things like that are kind of the most common side effects after vaccination and things that kids see after their vaccination with their routine vaccinations, as well," Candice Robinson, MD, the medical director for the Chicago Department of Public Health, told NBC Chicago. "No serious safety concerns have been identified with the use of Pfizer in this age group at this time."