An observational National Institutes of Health (NIH)-funded study suggests that COVID-19 vaccination is safe for kids 5 years and older who developed the rare but serious post-infection multisystem inflammatory syndrome in children (MIS-C).
In the multicenter study, published yesterday in JAMA Network Open, a team led by researchers from The Children's Hospital of Philadelphia and Harvard Medical School monitored 385 vaccine-eligible MIS-C survivors for adverse events at 22 US and Canadian medical centers (21 in the United States). Nearly half (48.1%) received at least one vaccine dose at least 90 days after MIS-C diagnosis from Dec 13, 2021, to Feb 18, 2022.
The median interval from diagnosis to the first vaccine dose was 9.0 months. Nearly all (98.9%) of vaccinated participants were given the Pfizer/BioNTech COVID-19 vaccine, with 16.8% receiving one dose, 76.8% receiving two doses, and 6.5% receiving three.
Of the vaccinated patients, 73.5% were boys, 31.9% were Hispanic, 28.6% were White, 24.3% were Black, 7.6% were of unknown race, 4.9% were Asian, 2% were of another race, 1.1% were multiracial, and 0.5% were American Indian/Alaska Native. The median age was 12.2 years.
No reports of myocarditis, MIS-C recurrence
Ninety or more days after vaccination, mild adverse reactions occurred in 48.6% of patients, mostly in the form of arm soreness (33.5%) and/or fatigue (17.3%), but no serious adverse events such as myocarditis (inflammation of the heart muscle) or recurrence of MIS-C were reported. The study authors said the proportion of children affected was similar to that previously reported in the general population.
A total of 17.3% of patients with adverse reactions were given medications, most often acetaminophen (11.4%) or ibuprofen (5.9%). Four patients (2.2%) sought medical care, but none were tested or hospitalized.
"These findings suggest that the safety profile of COVID-19 vaccination administered at least 90 days following MIS-C diagnosis appears to be similar to that in the general population," the study authors wrote.
In an NIH news release, the researchers said that the findings should reassure families and healthcare professionals that COVID-19 vaccination is safe for MIS-C survivors, adding that the US Centers for Disease Control and Prevention (CDC) recommend vaccination for this group.
These findings suggest that the safety profile of COVID-19 vaccination administered at least 90 days following MIS-C diagnosis appears to be similar to that in the general population.
More than 9,000 US children have been diagnosed as having MIS-C, and 74 have died, but the disease appears to be on the decline, the authors said. "A big part of that decline is that COVID vaccination has been protective against this rare condition in those who have received it," co-lead investigator Audrey Dionne, MD, of Harvard Medical School, said in the release.