Harvard Health Letter
Is it too late to get a flu shot?
Ask the doctor Q. I haven't gotten my flu shot yet, but now it's later in the flu season. Is it too late? A. Typically, winter epidemics of influenza (“flu”) hit hardest in December through February. But they can start as early as late September and last as late as May. So the best time to get your annual flu shot is in mid-October. However, if December has arrived and