concern that they could get sicker and are at a higher risk for spreading it to others. jim? >> understood. interesting to watch. elizabeth cohen, thank you very much. all right, joining me now to answer your and my questions, dr. paul offit, a member of the fda's vaccine advisory committee. great to have you back. first, big picture. we talked a couple of weeks ago very early in the omicron wave, i'm curious what you learned since then in looking at the data from south africa, israel, what we have begun to see in europe and also here about how serious illness omicron causes. have you learned anything? is it pointing towards the direction that this might cause less severe illness? >> right, i think we learned from south africa, their experience. what happened with -- in south africa, was initially they had a big wave of the beta variant or the south african variant had a