title: Disparities in influenza mortality and transmission related to sociodemographic factors within Chicago in the pandemic of 1918.
abstract: Social factors have been shown to create differential burden of influenza across different geographic areas. We explored the relationship between potential aggregate-level social determinants and mortality during the 1918 influenza pandemic in Chicago using a historical dataset of 7,971 influenza and pneumonia deaths. Census tract-level social factors, including rates of illiteracy, homeownership, population, and unemployment, were assessed as predictors of pandemic mortality in Chicago. Poisson models fit with generalized estimating equations (GEEs) were used to estimate the association between social factors and the risk of influenza and pneumonia mortality. The Poisson model showed that influenza and pneumonia mortality increased, on average, by 32.2% for every 10% increase in illiteracy rate adjusted for population density, homeownership, unemployment, and age. We also found a significant association between transmissibility and population density, illiteracy, and unemployment but not homeownership. Lastly, analysis of the point locations of reported influenza and pneumonia deaths revealed fine-scale spatiotemporal clustering. This study shows that living in census tracts with higher illiteracy rates increased the risk of influenza and pneumonia mortality during the 1918 influenza pandemic in Chicago. Our observation that disparities in structural determinants of neighborhood-level health lead to disparities in influenza incidence in this pandemic suggests that disparities and their determinants should remain targets of research and control in future pandemics.
authors.affiliation: Department of Biology, University of Florida, Gainesville, FL 32611.|Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611.
authors.forename: Kyra H
authors.initials: KH
authors.lastname: Grantz
authors.affiliation: Department of Epidemiology, University of Washington, Seattle, WA 98195.
authors.forename: Madhura S
authors.initials: MS
authors.lastname: Rane
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205.|Mathematical Modelling Unit, Institut Pasteur, Paris 75015, France.
authors.forename: Henrik
authors.initials: H
authors.lastname: Salje
authors.affiliation: Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611.|Department of Geography, University of Florida, Gainesville, FL 32611.
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Glass
authors.affiliation: Epidemiology, Worldwide Safety & Regulatory, Pfizer Inc., New York, NY 10017.
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Schachterle
authors.affiliation: Department of Biology, University of Florida, Gainesville, FL 32611; datc@ufl.edu.|Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611.|Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205.
authors.forename: Derek A T
authors.initials: DA
authors.lastname: Cummings
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D049673:History, 20th Century; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053118:Influenza A Virus, H1N1 Subtype / Q000472:pathogenicity; D007251:Influenza, Human / Q000401:mortality* / Q000473:pathology / Q000821:virology; D008297:Male; D008875:Middle Aged; D058873:Pandemics / Q000266:history*; D011014:Pneumonia / Q000401:mortality* / Q000473:pathology / Q000821:virology; D012959:Socioeconomic Factors; D055815:Young Adult
keywords: 1918; influenza; mortality; sociodemographic; transmission