COVID-19 infection vs vaccine side effects: Here’s what Lancet report on children below 18 reveals

There has been much speculation about the COVID‑19 virus, vaccine and its potential side effects, but this study may put those concerns into perspective.

According to an England-based study, the largest of its kind, children and young people face a higher risk of rare but serious heart and inflammatory complications from COVID‑19 infection than from vaccination. Analyzing health records for nearly 14 million children aged 18 and under, covering 98 percent of the population.

Researchers discovered that COVID‑19 infection carries elevated risks of vascular and inflammatory diseases for up to 12 months, while the Pfizer‑BioNTech vaccine slightly raises the risk of myocarditis or pericarditis for about four weeks, though far less than infection itself. Between January 2020 and December 2022, roughly 3.9 million children were diagnosed with COVID‑19, compared with about 3.4 million who received the vaccine.


The study, titled “Vascular and inflammatory diseases after COVID-19 infection and vaccination in children and young people in England: a retrospective, population-based cohort study using linked electronic health records,” was published in The Lancet Child and Adolescent Health. It was led by Dr. Alexia Sampri of the University of Cambridge’s Cardiovascular Epidemiology Unit, along with a team of researchers including Wen Shi, Thomas Bolton, Samantha Ip, Rochelle Knight, Venexia Walker, Rachel Denholm, Elena Raffetti, Spencer Keene, Elias Allara, Xiyun Jiang, and senior authors such as Prof. William N. Whiteley and Prof. Angela M. Wood, among others, representing the CVD-COVID-UK/COVID-IMPACT Consortium and the Longitudinal Health Wellbeing COVID-19 National Core Study.

COVID‑19 caused 2.24 extra heart inflammation over six months per 100,000 children versus 0.85 after vaccination. These results and the study offer important data to help policymakers weigh the relative risks of infection versus vaccination in younger populations.

Dr. Alexia Sampri said, “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 examined health issues, including inflammatory conditions, blood clots, low platelet counts, and inflammation of the heart or its surrounding tissue, known medically as myocarditis and pericarditis.

After the first COVID‑19 infection, risks of the five studied conditions peaked in the first four weeks and remained elevated for up to a year compared to uninfected children.

Rare cases of myocarditis have also been reported in young people shortly after receiving mRNA-based vaccines. Myocarditis is inflammation of the heart muscle that can affect its ability to pump blood effectively.

Co-author Professor Angela Wood explained, “Whilst vaccine-related risks are likely to remain rare and short-lived, future risks following infection could change as new variants emerge and immunity shifts. That’s why whole-population health data monitoring remains essential to guide vaccine and other important public health decisions.”