Hours after the Food and Drug Administration (FDA) authorized a fourth shot of the Moderna and Pfizer COVID-19 vaccines for all Americans 50 and older, an FDA official said a fifth shot may be needed in the fall. “I don’t want to shock anyone but there may be a need for people to get an additional booster in the fall, along with a more general booster campaign if that takes place, because we may need to shift over to a different variant coverage,” Dr. Peter Marks, head of the FDA center that regulates vaccines, told reporters on a call on March 29. The fresh emergency use authorization is for a fourth shot for Americans 50 and up and a fifth shot for people as young as 12 with weakened immune systems. The boosters from Moderna and Pfizer target the strain of SARS-CoV-2, or the CCP (Chinese Communist Party) virus, that was circulating in …