It's safe for kids to take the COVID-19 vaccine after they've suffered a rare complication from a prior COVID infection, a U.S. National Institutes of Health-supported study has concluded.
Multisystem inflammatory syndrome in children (MIS-C) affects about 1 in every 3,000 to 4,000 kids who contract COVID-19, according to the U.S. Centers for Disease Control and Prevention.
The complication, which occurs a few weeks after COVID-19 infection, involves an intense immune response that can lead to life-threatening organ failure. Seventy-four deaths in the United States have been linked to MIS-C during the pandemic, the CDC says.
A lingering question of COVID vaccine safety is how it might affect the more than 9,000 children and adolescents who've been diagnosed with MIS-C, the researchers noted.
To figure that out, 22 North American medical centers enrolled 385 children aged 5 and older who'd had MIS-C from an earlier COVID infection but were now eligible to receive the vaccine.
Of the group, about half received at least one vaccine dose. The average length of time between MIS-C diagnosis to the first vaccine dose was 9 months.
The average age of participants in the study was 12 years old, and about 74% were boys. Participants were racially diverse.
The report was published online Jan. 3 in JAMA Network Open.
Mild side effects like arm soreness and fatigue occurred in 49% of those taking the jab, a proportion similar to that of the general population, the researchers found. There were no reports of serious complications like inflammation of the heart (myocarditis), or recurrence of MIS-C.
“We are very reassured by the results, and this safety data should be comforting to families and health care professionals when considering and recommending vaccination,” study co-leader Dr. Matthew Elias said in an NIH news release. He is a pediatric cardiologist at Children's Hospital of Philadelphia and clinical assistant professor of pediatrics at the University of Pennsylvania.
The findings support CDC's recommendation that patients who've had MIS-C receive a COVID-19 vaccine at least 90 days after diagnosis, said study co-leader Dr. Audrey Dionne, a pediatric cardiologist at Boston Children's Hospital and assistant professor of pediatrics at Harvard Medical School.
MIS-C appears to be on the decline, other studies have reported.
“A big part of that decline is that COVID vaccination has been protective against this rare condition in those who have received it,” Dionne said.
The researchers will continue to track patients who've had MIS-C. While many make a full clinical recovery, some studies suggest that chronic symptoms from the illness could continue for some time to come.
The U.S. Centers for Disease Control and Prevention has more about multisystem inflammatory syndrome.
SOURCE: U.S. National Institutes of Health, news release, Jan. 3, 2023