By following the science developed by world-renowned experts, Japan has been able to avoid the worst effects of the pandemic without mandatory lockdowns. How have we done it? High-quality medical care—accessible to all thanks to universal health insurance—no doubt helps. Social and cultural factors might be at play, too.
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However, the core insight that has helped us in our fight against Covid-19 is the notion of transmission clusters. Early on, our health experts noticed that the disease spreads in a peculiar way… Most who are infected by it—about 80%—never pass it on to anyone else. The bulk of infections can be traced to a small number of “super-spreading events.”
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First, Japanese health experts recommended a special kind of contact tracing called “retrospective tracing.”… By mapping them and cross-referencing them with those of other infected people, tracers can identify common sources of infection—the people and places behind an infection cluster.
Second, we developed a guide for avoiding high-risk situations. We call them the “three Cs”: closed spaces, crowded places and close-contact settings, especially those involving loud talking. These settings all pose a major risk of infection. Today, thanks to extensive public-awareness campaigns, even children in Japan know to avoid them.