On July 14, 2022, the Public Health Agency of Canada (PHAC) released recommendations from the National Advisory Committee on Immunization (NACI) regarding the use of Moderna Spikevax COVID-19 vaccine in children aged 6 months to 5 years. This guidance is based on current evidence and NACI’s expert opinion. Health Canada authorized Moderna Spikevax (25 mcg) mRNA COVID-19 vaccine for use as a two dose primary series in children aged 6 months to 5 years.

NACI reviewed clinical trial data on the safety, efficacy, and immune response generated by Moderna Spikevax (25 mcg) COVID-19 vaccine in children aged 6 months to 5 years, as well as the spread and severity of COVID-19 in children under 5. For children 6 months to 5 years old, NACI recommends that:

  1. A primary series of two doses of Moderna Spikevax (25 mcg) COVID-19 vaccine may be offered to children aged 6 months to 5 years who do not have contraindications to the vaccine, with a dosing interval of at least 8 weeks between the first and second dose. (Discretionary NACI recommendation)
  2. A primary series of three doses of Moderna Spikevax (25 mcg) COVID-19 vaccine may be offered to children aged 6 months to 5 years who are moderately to severely immunocompromised, with an interval of 4 to 8 weeks between each dose. (Discretionary NACI recommendation)
  3. At this time, Moderna Spikevax (25 mcg) COVID-19 vaccine should not routinely be given concurrently (i.e., same day) with other vaccines. (Strong NACI recommendation)

As this is a newly authorized COVID-19 vaccine in this age group, NACI recommends that Moderna Spikevax (25 mcg) COVID-19 vaccine should be given 14 days before or after a different vaccine. This will help to determine if a potential side effect is due to Moderna Spikevax (25 mcg) COVID-19 vaccine or a different vaccine. A shorter interval between the administration of Moderna Spikevax (25 mcg) vaccine and a different vaccine may be warranted in some circumstances at the discretion of a health care provider.

Why should I get my 6 month – 5-year-old Immunized for COVID-19

Most children who get COVID-19 have mild or asymptomatic disease; however, some children experience severe disease and require hospitalization. Children who have had COVID-19 are at risk of experiencing multisystem inflammatory syndrome in children (MIS-C), a rare but serious complication from COVID-19 that usually requires hospitalization. Children who have an underlying medical condition are at higher risk of severe outcomes from COVID-19, but severe disease and MIS-C can occur in any child, even those without an underlying condition.

Clinical trial findings show a Moderna Spikevax 25 mcg dose primary series, produces an immune response in children under the age of 5 equivalent to the immune response seen in young adults aged 18 to 25 years who receive the 100-mcg dose primary series. Preliminary efficacy of the vaccine in preventing symptomatic COVID-19 when Omicron is the dominant variant, is estimated at 50.6% in children aged 6 to 23 months and 36.8% in children 2 to 5 years of age starting 14 days after the second dose.

Clinical trial data shows Moderna Spikevax (25 mcg) COVID-19 vaccine was well tolerated in children 6 months to 5 years of age. No safety signals were reported in the trial. It is important to note, due to the size of the trial, it is unlikely that adverse events occurring at a frequency less often than 6 in 10,000 people would be detected. NACI, Health Canada and PHAC will continue to closely monitor real world data from the use of this vaccine for potential rare and very rare side effects.

My child is healthy, and I have been told children are not impacted by COVID-19. Why should I get my child vaccinated?

Even though COVID-19 infections are relatively milder in many children, we still do not know the long-term impact of COVID-19 infections in children or adults. Being vaccinated reduces the risk of serious complications, including hospitalization and death. Recently, children 5 to 11 years old have become the population with the highest incidence of confirmed COVID-19 infections, although their hospitalization rate has remained low.

Children who get COVID-19 are at risk of developing multisystem inflammatory syndrome in children (MIS-C), which is a serious though uncommon condition. MIS-C is estimated to affect 0.5-3.1% of all children diagnosed with COVID-19, and 0.9-7.6% of hospitalized pediatric COVID-19 patients. Most MIS-C cases recover fully, and no MIS-C-associated deaths have been reported in Canada to date. While evidence is limited in pediatric populations, children may also be at risk of developing so-called “long-haul COVID” (post-acute COVID-19 syndrome).

Children with certain underlying chronic medical conditions have an increased risk of severe COVID-19 disease, but evidence specific to the aged 5 to 11 group is limited. For children under 18, the research has shown:

  • 39 per cent of hospitalizations had at least one underlying comorbidity.
  • An increased risk of ICU admission for those with chronic pulmonary disease, congenital heart disease, or neurological disorders.
  • 75 per cent who required mechanical ventilation had comorbidities, most commonly chronic cardiac disease, immunosuppression, chronic respiratory disease, and obesity.
  • Multiple comorbidities, obesity, neurological disorders, feeding tube dependence, Down Syndrome, immunocompromising conditions, and living in group settings as risk factors for severe COVID-19 infection.

Along with the physical health risks posed by COVID-19, the pandemic and public health response have indirectly but significantly affected the mental health and physical well-being of children: disruptions in family routines, school, educational activities, and sports; separation from friends, grandparents, and other close family members. In addition, the pandemic and public health measures may further exacerbate social inequities among racialized and Indigenous communities, refugees and other newcomers to Canada, persons living in low-income settings, as well as children with disabilities.

Children also transmit COVID-19, although it’s not clear how important they are to transmission in different settings. Research on household transmission has reported children aged 0 to 3 have greater odds than older children of passing on the disease to household contacts.

Is the dosage different for children 11 and under?

Each dose is 0.2 mL and contains 10 mcg of SARS-CoV-2 spike protein mRNA (compared with 30 mcg of mRNA in a 0.3 mL dose of vaccine for older children).

A buffer ingredient, tromethamine, has been added to facilitate storage. Tromethamine (also known as “trometamol” or “tris”) is present in vaccine and has been used for many years in some routine childhood vaccines, as well as in other injectable medications, without safety concerns. Allergies to tromethamine have been reported but are extremely rare.

When can I get the second dose for my child?

The National Advisory Committee on Immunization (NACI) recommends two doses of the Pfizer-BioNTech COVID-19 vaccine (10 mcg per dose) for children 5 to 11 years of age, with at least eight weeks between the first and second dose. Children who are moderately or severely immunocompromised should receive three doses, with the third dose given at least 28 days after the second.

What are the potential side-effects of the COVID-19 vaccine for my child?

The Pfizer vaccine clinical trial in children aged 5 to 11 years old followed 1,518 children receiving the vaccine and 750 receiving placebo for at least two months. Another 1,591 children receiving the vaccine were followed for adverse effects for a median of 2.4 weeks. Interim findings indicated the vaccine’s efficacy against symptomatic disease and its immune response were similar to those in adolescents and young adults.

Local reactions were very common, mostly mild to moderate in severity and more frequent than in older children. Side effects, predominantly fatigue, headaches, muscle pain, chills, fever, and joint pain, occurred more frequently after the second dose and were mostly mild or moderate. Common immune responses in 5 to 11 year olds were fewer than in adolescents and young adults. There were no cases of myocarditis or pericarditis or any other serious adverse event.

What is the risk of myocarditis (inflammation of the heart) from the vaccine?

Rare cases of myocarditis and/or pericarditis have been reported in adolescents and young adults after receiving the Pfizer vaccine (30 mcg), most commonly after the second dose and more often in males than females. Emerging Canadian safety surveillance data suggest longer wait times between the first and second dose of an mRNA COVID-19 vaccine may reduce the risk of myocarditis/pericarditis.

Data from the United States further suggest the risk of myocarditis/pericarditis from mRNA COVID-19 vaccination may be higher in adolescents aged 16 to 17 than in those aged 12 to 15.

As of now, the risk of myocarditis/pericarditis in children 5 to 11 years old immunized with the 10 mcg dose of the Pfizer vaccine is unknown. However, in general, myocarditis unrelated to the COVID-19 vaccine is less common in children this age than in older adolescents and young adults.

Is the risk of COVID-related myocarditis greater than that of the vaccine?

The risk of COVID-19 related myocarditis/pericarditis is much greater than the risk of vaccine-related myocarditis/pericarditis. Additional risks associated with COVID-19 infection are outlined above. The vaccine is very safe and effective at preventing COVID-19 infection, as well as severe outcomes from COVID-19.

My child is turning 12 in January, should I wait to get the adult dosage?

Currently, children are recommended to get the COVID-19 vaccine available to them. There is insufficient evidence that waiting improves the vaccine’s efficacy or change its risks, but it would increase the risk of catching COVID-19 in the interval.

If they get the pediatric dose for age 5-11 but they are 12 for their second dose, which will they receive?

Children who receive the 10 mcg Pfizer for their first dose and turn 12 years old before their second dose may receive the 30 mcg per dose Pfizer vaccine. However, if the second dose of 10 mcg is given instead, the dose is considered sufficient.

Will my child be forced to be vaccinated to attend school, events, or recreational activities?

Public health orders and vaccine requirements vary by local, provincial, and federal jurisdictions. Certain activities, such as flying on commercial airlines, may be restricted to those with up-to-date vaccinations or valid medical exemptions and proof of negative COVID-19 tests. We recommend checking with schools, events, and any other activities about restrictions prior to attending.

I want to get my child vaccinated for COVID-19, but they just had immunizations in school. Can I still get the COVID-19 shot?

NACI recommends waiting at least 14 days before or after receiving another vaccine before getting a COVID-19 vaccine. This waiting period is precautionary, and feasibility may be challenging for both health care providers and parents. Simultaneous administration or a shortened interval between vaccines may be decided on an individual basis by their health care provider.

Where can I find safe and trusted sources about the vaccine?

It is important to access reliable information when you are researching vaccines. Social media can be an easy and informative source; however, it is also easy for anyone to post misleading, non-factual information, and personal opinions.

The MNA has provided a list of sources to read about vaccines that are accurate and factual. You can find a list of these resources on our COVID-19 Resource Page.