>> any influenza that comes through comes through in waves. tbd be so many people are immune it won't take hold again. but you don't know that. it's unpredictable. that doesn't help us at all to decide what to do. it has not been -- it does not come back as hard in the places where you got -- >> we want to talk about the fear factor here. headline in "the new york times," why are we afraid of the new flu vaccine and bill maher, very popular guy, he tweeted to his 50,000 followers, warning about the new flu shot. there is a fear going on. >> warning what? >> i can't speak for bill maher. >> right. i don't think he's a scientist. >> no, no, but what he represents is a group of people who are afraid, not justified, sieps or otherwise, but you did a report last night where there has been a history with vaccines where it went wrong.