(MENAFN) Children and adolescents face significantly higher and more prolonged risks of rare heart and inflammatory complications from COVID-19 than from vaccination, according to new research published in The Lancet Child and Adolescent Health.

The landmark study—the largest of its kind in this age group—was conducted by scientists from the Universities of Cambridge and Edinburgh, and University College London.

Researchers analyzed electronic health records of nearly 14 million children in England under 18, spanning January 2020 to December 2022 and covering 98% of this population. During this period, 3.9 million children received a first COVID-19 diagnosis, while 3.4 million were administered their first dose of the Pfizer–BioNTech vaccine, the primary vaccine for 5–18-year-olds during the study period.

Although the overall incidence of heart and inflammatory complications was low, the study found the risk after infection was “much higher and longer-lasting” compared with vaccination.

Principal author Dr. Alexia Sampri, of the Cardiovascular Epidemiology Unit at the University of Cambridge, stated: “Our whole-population study during the pandemic showed that although these conditions were rare, children and young people were more likely to experience heart, vascular or inflammatory problems after a COVID-19 infection than after having the vaccine — and the risks after infection lasted much longer.”

The research assessed both short- and long-term risks for conditions including myocarditis and pericarditis (inflammation of the heart and surrounding tissue), blood clots, low platelet counts, and other inflammatory complications.

Following a COVID-19 diagnosis, the risk for all five conditions peaked within the first four weeks, with some remaining elevated for up to a year. By contrast, after vaccination, only a brief increase in myocarditis or pericarditis was observed during the first four weeks, after which risk levels returned to baseline.

MENAFN05112025000045017169ID1110299071