Pfizer Exec: Patients May Need More Doses of COVID Vaccine That’s according to Pfizer chief executive Albert Bourla said Thursday that a third dose would be followed by annual vaccinations. “There are vaccines like polio where one dose is enough, and there are vaccines like flu that you need every year, ” Bourla said during a conversation hosted by CVS Health. “The Covid virus looks more like the influenza virus than the polio virus.” The report says Bourla expounded on his claim. Mr. Bourla said that “a likely scenario” is “a third dose somewhere between six and 12 months, and from there it would be an annual re-vaccination.”