Some of the previous numbers from delta and the original wuhan strain. >> so get your boosters is the message on that front. so we know this week the cdc announced masks will be required at least until may 3rd and this is on planes, trains, buses that sort of thing. after that they'll reevaluate, but two weeks, is that premature at this point given what we know seen on the mask requirement for travel? >> just to be objective about it, there are two camps in this. number one there's a lot more travel going on because of spring break and we have people, still kids under five can't get immunized....