ArticlePloS one2021
Population density and basic reproductive number of COVID-19 across United States counties.
Article in PloS one, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 98 papers.
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Who cites it
98 citing papers in PubMed.
- Hesitancy Toward a COVID-19 Vaccine.EcoHealth · 2021Trial
- Decoding Viral Transmission Dynamics in Structured Populations Using a Microfluidic Herd-Immunity-on-a-Chip Platform.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2026Article
- Preliminary Study on the Development of a Transmission Model for Canine Distemper Virus in Wildlife Populations Using Heat Mapping and the Basic Reproduction Number.Veterinary sciences · 2026Article
- Modeling the impact of hospitalization-induced behavioral changes on the spread of COVID-19 in New York City.Infectious Disease Modelling · 2025Article
- How Population Structure and Nest Membership Shape Pathogen Patterns in Bumble Bees.Molecular ecology · 2025Article
- Clustering-based methodology for comparing multi-characteristic epidemiological dynamics with application to COVID-19 epidemiology in Europe.Royal Society open science · 2025Article
- The Covid-19 hospitalization risk associated with air pollution in New York state counties after the 2023 Quebec wildfires.Journal of public health research · 2025Article
- The effectiveness of the states' crisis response policies: Survival analysis on the COVID-19 transmission suppression in the United States.Health policy OPEN · 2025Article
- Methodology of Epidemic Risk Analysis in the Naval Military.International journal of environmental research and public health · 2025Review
- Scaling COVID-19 rates with population size in the United States.Journal of the Royal Society, Interface · 2025Article
- Geosocial Media's Early Warning Capabilities Across US County-Level Political Clusters: Observational Study.JMIR infodemiology · 2025Observational
- Measuring influencing factors affecting mortality rates during the COVID-19 pandemic.Global health action · 2024Article
- Early COVID-19 Pandemic Preparedness: Informing Public Health Interventions and Hospital Capacity Planning Through Participatory Hybrid Simulation Modeling.International journal of environmental research and public health · 2024Article
- Article
- Socioeconomic factors and COVID-19 mortality in immune-mediated rheumatic diseases patients: regional analysis from Argentina, Mexico and Brazil.Advances in rheumatology (London, England) · 2024Article
- What makes health systems resilient? An analytical framework drawing on European learnings from the COVID-19 pandemic based on a multitiered approach.BMJ public health · 2024Article
- The Impact of Wireless Emergency Alerts on a Floating Population in Seoul, South Korea: Panel Data Analysis.JMIR public health and surveillance · 2024Article
- Influence of Environmental Factors and Genome Diversity on Cumulative COVID-19 Cases in the Highland Region of China: Comparative Correlational Study.Interactive journal of medical research · 2024Article
- Risk perceptions and behaviors concerning rural tourism and economic-political drivers of COVID-19 policy in 2020.PloS one · 2024Article
- Controlling the first wave of the COVID-19 pandemic in Malawi: Results from a multi-round study.PLOS global public health · 2024Article
38 more citing papers are in PubMed but not listed here.
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3 authors.
Funding
Abstract
The basic reproductive number (R0) is a function of contact rates among individuals, transmission probability, and duration of infectiousness. We sought to determine the association between population density and R0 of SARS-CoV-2 across U.S. counties. We conducted a cross-sectional analysis using linear mixed models with random intercept and fixed slopes to assess the association of population density and R0, and controlled for state-level effects using random intercepts. We also assessed whether the association was differential across county-level main mode of transportation percentage as a proxy for transportation accessibility, and adjusted for median household income. The median R0 among the United States counties was 1.66 (IQR: 1.35-2.11). A population density threshold of 22 people/km2 was needed to sustain an outbreak. Counties with greater population density have greater rates of transmission of SARS-CoV-2, likely due to increased contact rates in areas with greater density. An increase in one unit of log population density increased R0 by 0.16 (95% CI: 0.13 to 0.19). This association remained when adjusted for main mode of transportation and household income. The effect of population density on R0 was not modified by transportation mode. Our findings suggest that dense areas increase contact rates necessary for disease transmission. SARS-CoV-2 R0 estimates need to consider this geographic variability for proper planning and resource allocation, particularly as epidemics newly emerge and old outbreaks resurge.
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