The Centers for Disease Control (CDC) has published the most extensive statistics yet involving reports of adverse events among children who received Pfizer’s Covid-19 vaccine.

According to CDC, there were about 400 cases of myocarditis, or inflammation of the heart muscle, reported in young people aged 12-17 after the Pfizer-BioNTech shot as of July 16.

According to the data, about 8.9 million children aged 12-17 had gotten the Pfizer-BioNTech shot as of July 16.

The Vaccine Adverse Event Reporting System (VAERS) received 9,246 reports of illnesses after the Pfizer shots in the youth age group; the vast majority for what CDC considers “nonserious events.”

About nine percent (9%) of the reports were for “serious adverse events” including myocarditis.