On the Daily Show with Trevor Noah on April 2, 2020, Bill Gates said:
Sadly, at some level of wealth, there’ll be countries that no matter how hard they try, they will have a widespread epidemic, and so again, sadly, the richer countries that do contain the epidemic will not allow people from those countries to come in unless they are quarantined, or tested or prove they are immune. And so this is gonna stop people going across borders, very dramatically these next few years, till we get to that full vaccination. Within the United States is different because we’re not gonna partition the country, and so therefore, we are all in it together, we can’t do what we’re gonna do with foreign nationals, which is reduce the numbers a lot and have very strict screening there. We’re not gonna have it at every state border, some complex quarantine center, and so the whole country needs, even when you have small numbers, because those can exponentiate to big numbers so quickly, the doubling time is like three days when you’re still behaving in the pre-epidemic way. So each country has to get the entire populous, even some who initially resisted, maybe for very good reasons, because the economic effect on them is strong. So this is powerful medicine, but if you take a big dose of it earlier, you don’t have to take it for nearly as long.