In fact, they do not know enough about those risks at all, which is why teens getting myocarditis after the second shot has made headlines. It was found in young Israeli males (they don’t vaccinate kids as young as the US yet) so very little to go off when trying to find individual risks for younger teens. You can’t make a proper risk-benefit calculation without this information.
In fact they're watching the issue very carefully, but given that myocarditis among those receiving the vaccine is no higher than myocarditis among that age group generally they're struggling to find a link.
Whereas they have quite clearly seen issues with myocarditis among children who have had Covid, as I posted above in a piece from Johns Hopkins, quoting staff from the multidisciplinary team at Kennedy Krieger Institute’s Pediatric Post COVID-19 Rehabilitation Clinic, which addresses lingering coronavirus symptoms in children and teens. I'll repeat in case you missed it.
www.hopkinsmedicine.org/health/conditions-and-diseases/coronavirus/covid-long-haulers-long-term-effects-of-covid19#:~:text=SARS%2DCoV%2D2,palpitations%20and%20rapid%20heartbeat.
Long-hauler coronavirus symptoms in children and teens
It’s not yet known whether children who have had COVID-19 are more or less likely than adults to experience continuing symptoms. But long-term COVID-19 in children is a possibility, showing up as fatigue, depression, shortness of breath and other long-hauler symptoms.
Amanda Morrow, M.D., a specialist in physical medicine and rehabilitation, is part of the multidisciplinary team at Kennedy Krieger Institute’s Pediatric Post COVID-19 Rehabilitation Clinic, which addresses lingering coronavirus symptoms in children and teens. She says it isn't clear why long COVID-19 symptoms affect some children and not others.
“We are seeing patients who are often very high-functioning, healthy children who did not have any previous illnesses or medical conditions,” she says, noting that many of the kids being treated at the clinic only had mild bouts of COVID-19.
Heart inflammation after COVID-19 is a concern, especially among young athletes returning to their sports after a mild or even asymptomatic case of the coronavirus. They should be screened for any signs of heart damage to ensure it is safe for them to resume activity.
Kids who have experienced the (thankfully) very rare complication of COVID-19 called multisystem inflammatory syndrome in children, or MIS-C, can be left with serious heart damage, and should be followed by a pediatric cardiologist.