Gates Package — page 974

f people around the world, nearly as overwhelming or Researchers have drawn other conclusions about the differences among and within countries. Contact tracing is more effective in places with a good system for reporting and processing the data about each person's contacts, though once the case numbers get high, it becomes much harder. Social distancing and lockdowns work better in richer countries than in poorer ones, for many of the same reasons as the disparity within the U.S. that I just described. In some countries, lockdowns can backfire, as the disease is spread by people who migrate (returning to their home community from a job in the city, for example). Lockdowns may not be necessary in places where the disease burden is modest. They're also more effective in countries where residents have less of a voice in the country's affairs, and the government is in a position to strictly enforce lockdowns and other mandates. What this all means is that there is no single ideal mix of NPIs that works equally well everywhere. Context matters, and protective measures need to be tailored for the places where they'll be used. The flu almost went away, at least for a while. In the fall of 2020, as we got closer to flu season, I started to worry. Every year, influenza kills tens of thousands of Americans10 and hundreds of thousands of people around the world, nearly all of them elderly.* Even more are hospitalized. At a time when COVID was overwhelming or * The estimates of how many people get sick and how many die from the flu every year vary widely. Deaths in particular are probably undercounted, because not all flu deaths get reported to infectious disease center like the CDC, and because flulike symptoms might not be reported on a death certificate.