One of the most concerning aspects of the ongoing COVID-19 pandemic is that it disproportionately affects people from some specific ethnic and socio-economic minorities. In particular, since from the beginning of the pandemic it has been clear that people from Black and African American backgrounds seem to be hit especially hard by the virus, creating a substantial infection gap. The observed abnormal impact on these ethnic groups could probably be due to the co-occurrence of other known risk factors, including co-morbidity, poverty, level of education, access to healthcare, residential segregation and response to cures, although those factors do not seem able to explain fully and in depth the excess incidence of infections and deaths among African Americans. Here, we introduce the concept of diffusion segregation, that is the extent to which a given group of people is internally clustered or exposed to other groups, as a result of mobility and commuting habits. By analysing census and mobility data on major US cities, we found that the weekly excess COVID-19 incidence and mortality in African American communities at the beginning of the COVID-19 pandemic is significantly associated with their level of diffusion segregation. The results confirm that knowing where people commute to, rather than where they live, is potentially much more important to contain and curb the spreading of infectious diseases.

中文翻译：

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非裔美国人社区中的扩散隔离和 COVID-19 不成比例的发病率

正在进行的 COVID-19 大流行最令人担忧的方面之一是它对来自某些特定种族和社会经济少数群体的人产生了不成比例的影响。特别是，自大流行开始以来，很明显，来自黑人和非裔美国人背景的人似乎受到病毒的打击特别严重，造成了巨大的感染差距。观察到的对这些族群的异常影响可能是由于其他已知风险因素的共同发生，包括合并症、贫困、教育水平、医疗保健、居住隔离和对治疗的反应，尽管这些因素没有似乎能够充分而深入地解释非裔美国人感染和死亡的高发率。在这里，我们引入了扩散分离的概念，这是由于流动性和通勤习惯，特定人群在内部聚集或接触其他人群的程度。通过分析美国主要城市的人口普查和流动数据，我们发现，在 COVID-19 大流行开始时，非裔美国人社区每周的 COVID-19 超额发生率和死亡率与其扩散隔离水平显着相关。结果证实，了解人们通勤的地点，而不是他们住的地方，对于遏制和遏制传染病的传播可能更为重要。我们发现，在 COVID-19 大流行开始时，非裔美国人社区每周的 COVID-19 超额发生率和死亡率与其扩散隔离水平显着相关。结果证实，了解人们通勤的地点，而不是他们住的地方，对于遏制和遏制传染病的传播可能更为重要。我们发现，在 COVID-19 大流行开始时，非裔美国人社区每周的 COVID-19 超额发生率和死亡率与其扩散隔离水平显着相关。结果证实，了解人们通勤的地点，而不是他们住的地方，对于遏制和遏制传染病的传播可能更为重要。