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Advisers to the Centers of Disease Control and Prevention met on Wednesday to discuss the possible link between myocarditis — inflammation of the heart muscle — and the two coronavirus vaccines that use mRNA, Pfizer and Moderna. They determined that while there is an association between the vaccines and myocarditis, all age groups eligible to receive them should continue to, including adolescents 12 and over.

This was the right decision based on a thoughtful weighing of risks and benefits. While myocarditis and an associated condition, pericarditis (inflammation of the lining around the heart), could be serious, the likelihood of this occurring is low and most cases are mild. By comparison, the risk of severe and lasting outcomes from covid-19 are much higher and can be prevented through vaccination.

Here’s what the CDC reported: Of the more than 300 million doses of the mRNA vaccines administered in the United States, there have been 323 documented cases of myocarditis, pericarditis or both, in those under 30. Most occurred after the second of the two-dose vaccination. The median age for those diagnosed with the conditions after the second dose was 24 years old, and 79 percent occurred in males. Symptoms generally started within three to four days. Of these 323 reports, nearly 80 percent are known to have recovered from their symptoms at this time. Nine are still hospitalized and two are in intensive care. No one has died.

That most cases are mild, treatable and do not leave lasting effects is crucial to assessing the potential harm of myocarditis. Some may question why the CDC isn’t advising to stop administration of the mRNA vaccines, when it paused the Johnson & Johnson vaccine after there were fewer than 10 reports of a rare blood clotting disorder. That condition was severe, difficult to treat, and caused debilitating strokes and deaths. Myocarditis, on the other hand, affects thousands of adults and children in the United States every year. It occurs as a result of other viruses such as influenza. Some medications, as well as parasitic and bacterial infections, can cause it, too. Covid-19 itself can lead to myocarditis; a study of nearly 1,600 collegiate athletes recovering from the coronavirus found that 2.3 percent have shown signs consistent with myocarditis.

And this is the most critical part of the argument: The risk of myocarditis from the vaccine must be weighed against the risk of adverse effects from covid-19. The CDC reports that adolescents and young adults now constitute 33 percent of all new covid-19 cases. Since the beginning of the pandemic, there have been 7.7 million infections in the 12 to 29 age group, resulting in 2,767 deaths. More than 300 of these deaths occurred since April 1.

More and more studies also point to long-term symptoms, even in people with mild or asymptomatic disease. In an analysis of medical records from nearly 2 million people who tested positive for covid-19, about 1 in 4 reported going to the doctor for symptoms they didn’t have before, including nerve and muscle pain, fatigue and foggy brain. Covid-19 is associated with lasting effects on virtually every organ system, leaving previously healthy people with new problems, such as exercise intolerance, lack of concentration and hair loss. Many also have been newly diagnosed with chronic diseases, such as hypertension, diabetes and kidney disease. A new report, not yet pre-reviewed, found that those recovered from both mild and severe coronavirus could have loss of brain tissue that may be irreversible.

Surely, covid-19 is something that no one wants to get. The question is: at what cost are people willing to avoid it? In their meeting with advisers, the CDC presented this crucial risk-benefit analysis: They calculated that for males between the ages of 18 and 29, every 1 million second vaccine doses would result in fewer than 60 cases of myocarditis. But those same vaccinations would prevent 12,000 infections, 530 hospitalizations and three deaths. For males between 12 and 17, every 1 million second doses could be linked to fewer than 70 myocarditis cases, preventing 5,700 infections, 215 hospitalizations and two deaths.

In light of these numbers, the decision to continue vaccinating teenagers and young adults is clearer than ever. It’s important to be aware of the rare association with myocarditis, and young males, in particular, should be on the lookout for symptoms in the week following vaccination, such as chest pain, shortness of breath and rapid or abnormal heart rhythm. The vast majority who are vaccinated will never have these symptoms, and instead, can return to school, sports and being with their friends with much less worry and fear of contracting — and spreading — covid-19.

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