Australian children aged 5-15 years report fewer side effects in the days following mRNA COVID-19 vaccination than those reported in clinical trials and published safety data, new AusVaxSafety-led research has found.
Researchers analysed 392,268 survey responses captured via AusVaxSafety’s national active vaccine safety surveillance system following mRNA COVID-19 vaccine encounters between July 2021 and May 2022.
In children aged 5-11 years, 25% of respondents reported at least one side effect in the first 3 days after Pfizer 10 micrograms dose 1 and 28% after Pfizer 10 micrograms dose 2.
In children aged 12-15 years, 32% of respondents reported at least one side effect in the first 3 days after Pfizer 30 micrograms dose 1; 49% after Pfizer 30 micrograms dose 2; 34% after Moderna 100 micrograms dose 1; and 64% after Moderna 100 micrograms dose 2.
Local reaction (including pain, itching, redness and swelling at injection site), fatigue, headache and muscle/joint pain were the most common side effects in both age groups. These side effects are known to occur after vaccination; they are generally mild and short-lived, with most resolving within one day or less.
The rate of side effects reported was similar across sex and Indigenous status, but increased with increasing age and was higher for children with parent-reported chronic medical conditions. Overall medical attendance rates remained low (0.3%) and overall impact on routine activities was also low (7%).
Lead author Associate Professor Nick Wood, Associate Director of Clinical Services and Vaccine Safety at the National Centre for Immunisation Research and Surveillance (NCIRS) said, “Australian data analysed to date are extremely reassuring and side effect rates in children aged 5-11 years are below what has been observed internationally for this age group.”
“Importantly fever, which is a concern in children under 6 years of age due to the potential for febrile seizures, was low in the youngest age group and similar to that seen following annual influenza vaccination.”
“No self-reported cases of myocarditis or pericarditis were identified in this study and these data provide confidence to parents on the safety of mRNA COVID-19 vaccines used in Australia,” added Associate Professor Wood.
AusVaxSafety continues to actively monitor COVID-19 vaccine safety in children, including Moderna 30 micrograms COVID-19 vaccine to children under 12 years of age and third doses. Safety data for these groups will be updated on the AusVaxSafety website.
AusVaxSafety will commence surveillance in children aged 6 months to 5 years once vaccines become available for use pending recommendations from the Australian Technical Advisory Group on Immunisation (ATAGI).
