pandemic. how hard would it be to replicate what you were able to do at the nfl? >> what prevented transmission was mask usage. avoiding in-person meetings. staying in the open air environments. not eating together. prompt symptom reporting. isolation of anyone exposed. >> reporter: now a summer surge fueled by the delta variant, dr. anthony fauci says the nfl's move could encourage others to enforce similar vaccine protocols to help slow the spread of the virus. >> i think the nfl is sending a very strong signal that it's very important to get vaccinated if you want to play football and you want to do it in a way that you are -- feel unrestricted and not worry about any penalties, you just get vaccinated.