The Brief The FDA, under Health Secretary Robert F. Kennedy Jr., has taken another step to question the safety of Covid-19 vaccines, going against prior findings of U.S. government scientists. Myocarditis, a type of heart inflammation that is usually mild, emerged as a complication after the first Covid shots became widely available in 2021. The Food and Drug Administration has expanded warnings about a rare heart side effect rarely seen in young men who take the two leading Covid-19 vaccines. FILE - Covid-19 vaccine (Photo illustration by Joe Raedle/Getty Images)Medical experts say vaccine rules are heading in the wrong direction. FDA Commissioner Marty Makary and a top deputy recently restricted annual COVID-19 shots to seniors and other Americans at higher risk from the virus.