{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:14:07Z","timestamp":1778199247411,"version":"3.51.4"},"reference-count":53,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,14]],"date-time":"2021-11-14T00:00:00Z","timestamp":1636848000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002322","name":"Coordena\u00e7\u00e3o de Aperfeicoamento de Pessoal de N\u00edvel Superior","doi-asserted-by":"publisher","award":["001"],"award-info":[{"award-number":["001"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The novel coronavirus disease 2019 (COVID-19) pandemic is an unprecedented global event that has been challenging governments, health systems, and communities worldwide. Available data from the first months indicated varying patterns of the spread of COVID-19 within American cities, when the spread was faster in high-density and walkable cities such as New York than in low-density and car-oriented cities such as Los Angeles. Subsequent containment efforts, underlying population characteristics, variants, and other factors likely affected the spread significantly. However, this work investigates the hypothesis that urban configuration and associated spatial use patterns directly impact how the disease spreads and infects a population. It follows work that has shown how the spatial configuration of urban spaces impacts the social behavior of people moving through those spaces. It addresses the first 60 days of contagion (before containment measures were widely adopted and had time to affect spread) in 93 urban counties in the United States, considering population size, population density, walkability, here evaluated through walkscore, an indicator that measures the density of amenities, and, therefore, opportunities for population mixing, and the number of confirmed cases and deaths. Our findings indicate correlations between walkability, population density, and COVID-19 spreading patterns but no clear correlation between population size and the number of cases or deaths per 100 k habitants. Although virus spread beyond these initial cases may provide additional data for analysis, this study is an initial step in understanding the relationship between COVID-19 and urban configuration.<\/jats:p>","DOI":"10.3390\/e23111512","type":"journal-article","created":{"date-parts":[[2021,11,14]],"date-time":"2021-11-14T20:48:36Z","timestamp":1636922916000},"page":"1512","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Understanding the Impact of Walkability, Population Density, and Population Size on COVID-19 Spread: A Pilot Study of the Early Contagion in the United States"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7501-1466","authenticated-orcid":false,"given":"Fernando T.","family":"Lima","sequence":"first","affiliation":[{"name":"Stuckeman Center for Design Computing, The Pennsylvania State University, University Park, State College, PA 16802, USA"},{"name":"Faculty of Architecture and Urbanism, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-900, Brazil"}]},{"given":"Nathan C.","family":"Brown","sequence":"additional","affiliation":[{"name":"Department of Architectural Engineering, The Pennsylvania State University, University Park, State College, PA 16802, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3826-3987","authenticated-orcid":false,"given":"Jos\u00e9 P.","family":"Duarte","sequence":"additional","affiliation":[{"name":"Stuckeman Center for Design Computing, The Pennsylvania State University, University Park, State College, PA 16802, USA"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Andersen, M. 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