Myocarditis and Pericarditis Observed in Children and Adolescents After COVID-19 Vaccination, But Rare: NHS Preprint

Adolescents had a higher incidence of post-vaccine myocarditis and pericarditis than children.

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Myocarditis and pericarditis only occur after vaccination according to a recent preprint led by researchers at Oxford University, which compared health outcomes among COVID-vaccinated and unvaccinated adolescents and children.

“Whilst rare, all myocarditis and pericarditis events during the study period occurred in vaccinated individuals,” the authors wrote. There were no deaths from myocarditis or pericarditis.

The primary conclusion of the broad study—which also looked at the effectiveness of the vaccine—was that vaccination in adolescents reduced COVID-19  hospitalisations, noting that such incidents in that age bracket are rare.

The study evaluated over 1 million English children aged 5 to 11 and adolescents aged 12 to 15. Vaccinated minors were compared to an equal number of unvaccinated, and children who took one dose were also compared to those who took two doses.

Vaccinated adolescents had significantly lower chances of testing positive for COVID-19 and needing COVID-related hospitalization and critical care compared to their unvaccinated counterparts. Vaccinated children, however, were not substantially different from unvaccinated children in terms of COVID-19 infection and hospitalization.

Additionally, “COVID-19-related hospitalisation, and critical care attendance were rare in both adolescents and children and there were no COVID-19 related deaths,” the authors observed.

18 Cases

The study analyzed data from the National Health Service (NHS) England’s OpenSAFELY-TPP database, which covers 40 percent of English primary care practices.

Vaccinated adolescents and children were matched to unvaccinated cohorts and followed for 20 weeks to compare positive COVID-19 tests, hospitalizations, COVID-19 critical care, adverse events, and non-COVID hospitalizations.

England’s data showed that myocarditis and pericarditis were only documented in the vaccinated.

The study did not directly compare the incidence of myocarditis and pericarditis in vaccinated individuals and those with COVID-19.

COVID-19 infection has been associated with a higher incidence of myocarditis, according to data from other studies.

Adolescents had a higher incidence of post-vaccine myocarditis and pericarditis than children.

There were 15 cases of pericarditis and three cases of myocarditis among more than 839,000 vaccinated children and adolescents. All of the myocarditis and 12 pericarditis cases appeared in the adolescent cohort.

Except for three pericarditis cases, all other cases occurred after the first vaccine dose. More than half of the adolescents with pericarditis and myocarditis were hospitalized or went to the emergency room. It is unknown how many adolescents needed critical care, though the maximum length of stay for myocarditis treatment was one day.

COVID-19 Hospitalization

The authors also compared myocarditis and COVID-19 hospitalization risks in the vaccinated.

While rare, children and adolescents were more likely to be hospitalized with COVID-19 than develop myocarditis or pericarditis, regardless of vaccine status.

Of the adolescents who took one dose of the COVID-19 vaccine, 33 were hospitalized from COVID-19, while three developed myocarditis. In the unvaccinated group, 57 were hospitalized.

The authors concluded that adolescents may have more to benefit from COVID-19 vaccines than children because compared to adolescents, children had a greater risk of myocarditis post-vaccination and a lower risk reduction of hospitalization due to COVID-19 infection.

Children Are Different

Vaccination appears to significantly reduce the risks of having severe COVID-19 outcomes for adolescents but not for children.

Of the over 552,000 unvaccinated children or adolescents, only three cases of COVID-19 required critical care. All three cases occurred among unvaccinated adolescents.

Furthermore, there was no significant difference in COVID-19 infection severity between vaccinated and unvaccinated children.

Since the appearance of COVID-19, researchers have been mystified by how young children have a survival advantage compared to adults. Infectious diseases often kill the very young and the very old; however, research has shown that COVID-19 usually spares infants.

Some researchers have reasoned that children are better protected because, compared to adults, they have a faster-responding innate immune system, often referred to as the first line of defense. This enables them to mount a robust defense against COVID-19 infections more quickly.

This article has been updated to reflect the fact that the study compared only the vaccinated to the unvaccinated. A previous version incorrectly indicated a comparison between vaccinated and COVID-19 infected individuals. The Epoch Times regrets this error.