Archive 18: Summary of National Advisory Committee on Immunization (NACI) statement: Recommendation on the use of mRNA COVID-19 vaccines in adolescents 12 to 17 years of age

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• Overview
• What you need to know
• Quotes

Overview

• On August 27, 2021, the Public Health Agency of Canada released updated advice from the National Advisory Committee on Immunization (NACI) on the use of mRNA COVID-19 vaccines in adolescents 12 to 17 years of age. This updated advice follows Health Canada's authorization of the Moderna COVID-19 vaccine for adolescents 12 years of age and older. This recommendation is based on current scientific evidence and NACI's expert opinion.
• Clinical trial findings suggest the Pfizer-BioNTech and Moderna mRNA vaccines provide very good protection against symptomatic COVID-19 infection and have a favourable benefit versus risk profile in adolescents 12 years of age and older.
• NACI considered the rare cases of myocarditis (inflammation of the heart muscle) and/or pericarditis (inflammation of the tissue surrounding the heart) following immunization with mRNA COVID-19 vaccines which have been reported both in Canada and internationally, when making this recommendation.
• NACI already recommended vaccination of adolescents with Pfizer-BioNTech COVID-19 vaccine following regulatory approval in May 2021, and now is including Moderna COVID-19 vaccine in those recommendations.

NACI continues to recommend:

• A complete series with an mRNA COVID-19 vaccine should be offered to adolescents 12 to 17 years of age who do not have contraindications to the vaccine.
• Informed consent should include a discussion about the rare risk of myocarditis and/or pericarditis following immunization with an mRNA COVID-19 vaccine. Individuals should be advised of the symptoms of myocarditis/pericarditis and to seek immediate medical attention should symptoms develop.
• As a precaution, people who experienced myocarditis and/or pericarditis after a first dose of an mRNA vaccine should wait to get their second dose until more information is available.
• Individuals who have a history of myocarditis unrelated to mRNA COVID-19 vaccination should consult their clinical team for individual considerations and recommendations. People previously diagnosed with myocarditis but who are no longer being followed by a medical professional for heart issues should receive the vaccine.

To see the full update, please visit NACI Recommendation on the use of mRNA vaccines in adolescents 12 to 17 years of age.

What you need to know

• In May 2021, NACI recommended that a complete series with the Pfizer-BioNTech vaccine should be offered to adolescents 12 to 17 years of age without contraindications. This advice followed Health Canada's authorization of the vaccine in adolescents 12 years of age and older.
• On August 27, 2021, Health Canada expanded the authorization of the Moderna vaccine to include adolescents 12 years of age and older following the results of a clinical trial in this population.
• Clinical trial findings suggest a complete series of an mRNA vaccine (Pfizer-BioNTech and Moderna) provide very good protection against symptomatic COVID-19 and have a favourable benefit versus risk profile in adolescents 12 years of age and older.
• Emerging evidence suggests that while the Delta variant is more transmissible, a complete two-dose vaccine series with an mRNA COVID-19 remains effective against severe health outcomes including hospitalization and death. Recently, breakthrough infections with the Delta variant have been more commonly reported than with other variants in the community.
• The majority of adolescents 12 years of age and older in Canada have already received one dose of the Pfizer-BioNTech vaccine as part of the adolescent COVID-19 vaccination program, which began in May 2021. As of August 21, 2021, more than 76% of adolescents 12 to 17 years of age have received at least one dose of an mRNA COVID-19 vaccine and more than 63% are fully vaccinated.
• There have been reports of myocarditis and/or pericarditis after immunization with mRNA COVID-19 vaccines in Canada and internationally. Based on international reports as of August 19, 2021, cases of myocarditis and/or pericarditis occur more often in adolescents and adults under 30 years of age, more often in males than in females, and more often after a second dose of an mRNA vaccine than after a first dose.
• While follow-up is ongoing, available data indicate that the majority of individuals affected have responded well to conservative therapy, and tend to recover quickly.
• Recently, a higher rate of cases of myocarditis and/or pericarditis has been reported after the administration of the Moderna vaccine compared to the Pfizer-BioNTech vaccine, although verification of this potential difference is ongoing.
• Some provinces and territories may decide to continue using the Pfizer-BioNTech vaccine for their adolescent program because there is more experience to date with the Pfizer-BioNTech vaccine in this age group and there is the possibility of a lower rate of myocarditis and/or pericarditis with this vaccine compared to the Moderna vaccine.
• For both mRNA vaccines, informed consent should include a discussion about the rare risk of myocarditis and/or pericarditis following immunization. People who receive mRNA vaccines should be advised to seek immediate medical attention if they develop symptoms, which may include chest pain, shortness of breath, or the feeling of a fast, pounding or fluttering heartbeat.
• As a precaution, NACI recommends that people who experienced myocarditis and/or pericarditis after a first dose of an mRNA vaccine should wait to get their second dose until more information is available.
• Individuals who have a history of myocarditis unrelated to mRNA COVID-19 vaccination should consult their clinical team for individual considerations and recommendations. People previously diagnosed with myocarditis who are no longer being followed by a medical professional for heart issues should receive the vaccine.
• The Public Health Agency of Canada and Health Canada will continue to collaborate with provincial and territorial authorities, vaccine manufacturers, international regulators and NACI to closely monitor cases of myocarditis and/or pericarditis following immunization with the mRNA COVID-19 vaccines.
• NACI continues to monitor the safety and effectiveness of mRNA vaccines in adolescents and will update recommendations as needed.

To see the full update, please visit NACI Recommendation on the use of mRNA vaccines in adolescents 12 to 17 years of age.

Quotes

"Following Health Canada's recent authorization for the use of Moderna in adolescents 12 to 17 years of age, NACI is recommending that a complete series with an mRNA COVID-19 vaccine should be offered to adolescents 12 to 17 years of age without contraindications. Both mRNA vaccines are very effective at preventing COVID-19 illness and have so far continued to show good effectiveness against variants, including Delta.

It is important to be aware that rare cases of myocarditis/pericarditis following receipt of an mRNA vaccine have been reported, and NACI continues to follow the evidence related to this safety issue closely. We have seen that myocarditis/pericarditis appears to be reported more often in young males and after the second dose. More recently, we have seen that there may also be a difference in risk between different vaccine products, and this continues to be investigated. Considering the rare risks and known benefits of COVID-19 vaccines, vaccination is strongly recommended for adolescents to prevent severe illness and to allow teenagers to safely resume activities central to their health and well-being, such as in-person schooling and events with family and friends."

Dr. Shelley Deeks, NACI Chair

"I would like to thank the experts on NACI for their continued guidance on the use of mRNA vaccines in adolescents. Since May, provinces and territories have done a great job rolling out the Pfizer-BioNTech vaccine to adolescents and have made significant progress in increasing vaccine coverage in this age group across Canada. As of August 21st, more than 76% of adolescents aged 12 to 17 years have received one dose and more than 63% are fully vaccinated. NACI's updated recommendations will help provinces and territories continue to rollout their adolescent COVID-19 vaccination programs to better protect the health and wellbeing of our adolescents, their families and communities."

Dr. Theresa Tam, Chief Public Health Officer