Practically everybody will be directed in the future to get a booster dose of a COVID-19 vaccine, Dr. Anthony Fauci signaled on Tuesday. “Ultimately I believe that the optimal regimen for the vaccine for the mRNAs is going to include that third booster shot,” Fauci, the director of the National Institute of Allergy and Infectious Diseases, said during a remote talk held as part of the Atlantic Festival. Three doses will become “the proper, complete regimen,” he also said. The two most widely used COVID-19 vaccines, from Pfizer and Moderna, use messenger RNA technology. The vaccines were originally recommended as a two-dose regimen but Biden administration officials recently allowed and recommended third shots for multiple population groups, including everybody 65 or older. Experts advising the Centers for Disease Control and Prevention (CDC) said that data so far show the vaccines continue to work well in terms of preventing hospitalization and death …