second, asking people to be isolated longer than they need to be. it is hugely burdensome to them. i think this cdc move is exactly right. if people follow what cdc laid out, it will still keep people safe and let them get out of isolation more quickly. >> and, doctor, you made the point, this is about incentive structures and if there is a more reasonable window, rooted in sound science, that will increase people's ability or instinct to participate. we see the distinction between asymptomatic cases and symptomatic, but what about for folks vaccinated versus unvaccinated? should there be a distinction there? >> i think there is. i -- even though i applaud the cdc's decision, this is not how i would have done it. i think they should have done this a bit differently for vaccinated versus unvaccinated. we know -- when they have a breakthrough infection shed for much shorter period of time, so this is really reasonable for vaccinated people. i think they could have made that distinction, i wish they had. >> i do think it is surprising they did not make that distinction or recommend that