demand. for most of the world, it's the reverse, a lot of demand but not enough supply. it will make a difference. you can get a sense of the scale of what they're trying to talk about here, these mass world vaccination programs, they're audacious. the thing about it is, you've got to make the vaccine, but then you've got to distribute it to some pretty hard to access areas around the world. then you have to have people over there that can give the shots. remember you need personnel, who can do that work as well. you have to build up infrastructure which i think the president is talking about. from a public health standpoint, it's -- i think it's the most audacious task we take on as a world. >> one thing you just mentioned, having the right people, the right storage, the right chain of custody, infrastructure in place in some of these countries, is a real problem.