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People who see people: How high mixers help spread COVID-19

Some people interact with many others in the course of a day; others see very few. Sounds basic, but it’s a critical distinction, often overlooked in epidemiological models, and may explain the sharp rise and recent fall in US COVID-19 cases.

The dynamics of uneven mixing can expand COVID-19 transmission.
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To read more, see “All in the mix: Why US COVID-19 cases rose and fell, and what comes next,” March 29, 2021.