dr. fauci said today that there will be boosters but not right now for everyone. give us a rough timeline. when are we roughly talking about that the other 97% of americans get their third shot? >> you know, mehdi, i don't entirely know the answer to that. it depends on watching closely the data in the coming weeks because the big wrinkle in our plans is called delta. you knee that the vaccine antibody levels were going to gradually drop over time. they have been doing that, but slowly, and right now, we're still fine. if you have full immunization from pfizer, moderna, or j&j, you're covered. but delta comes along and it's harder to deal with. as we look week after week since delta has taken over the country, we'll figure out what the timing is. not yet, but it could well be some time later this fall or early next year. >> later this fall or early next year. many of our viewers are marking their diaries right now.