COVID-19 affects children differently than adults. There is a lower percentage of COVID related hospitalizations, ICU admissions, deaths, and severe complications/outcomes with children. But children with COVID-19 infection are at risk of MIS-C (multisystem inflammatory syndrome). MIS-C is a rare but serious syndrome that can occur several weeks after a COVID-19 infection. Myocarditis and pericarditis can also occur as a complication of COVID-19 infection in children, but this is rare.
In Canada, there have been reported cases of myocarditis and pericarditis in people 12 years and over who received the 30mcg dose of the Pfizer-BioNTech COVID-19 vaccine or the 100mcg dose of the Moderna COVID-19 vaccine. It is important to note that the risk is rare.
Currently, the risk of myocarditis/pericarditis in children following immunization with the recommended 5–11-year-old 10mcg dose of the Pfizer-BioNTech vaccine is unknown. Based on the studies done so far, myocarditis and/or pericarditis were not detected. Safety surveillance data from individuals aged 12 and older does not suggest the risk of myocarditis/pericarditis following mRNA COVID-19 vaccination would be greater in children aged 5-11 years compared to older populations. Also, data from older age groups also suggests that an extended interval between the first and second dose (at least 8 weeks) may also be associated with a reduced risk of myocarditis/pericarditis following a second dose of an mRNA COVID-19 vaccine.
Children who have a history of myocarditis unrelated to mRNA COVID-19 vaccination should consult their health care provider for recommendations. Please seek medical attention if your child develops symptoms including chest pain, shortness of breath, or palpitations following immunization with the Pfizer-BioNTech vaccine.
Health Canada, the Public Health Agency of Canada and NACI (National Advisory Committee on Immunization) will continue to monitor and review the emerging evidence on the safety and effectiveness of the vaccine. They will update their recommendation, as well as its strength, as the evidence base evolves.