Known since 2020: "CHOP Researchers Find Elevated Biomarker Related to Blood Vessel Damage in All Children with SARS-CoV-2 Regardless of Disease Severity"

From 2022 It is not just adults that die from COVID-19. A recent study in Japan looked at 41 children under the age of 20 who were infected and died between January and August of this year, 73% within a week after symptom onset

From 2020: "Virtually all children infected with COVID-19 show signs of blood vessel damage, study shows"