The Centers for Disease Control and Prevention this week quietly changed its vaccine recommendations for males between the ages of 12 and 39 to reduce the risk of myocarditis, encouraging them to wait for eight weeks after their first dose of an mRNA COVID-19 vaccine to get their second dose -- a longer timeframe than CDC’s previously recommended three to four weeks between the doses. The two mRNA vaccines authorized for use in the United States, developed by Pfizer and...