Geographic concentration of SARS-CoV-2 cases by social determinants of health in metropolitan areas in Canada: a cross-sectional study

Background: Understanding inequalities CoV-2 in each city, and calculated Gini in SARS-CoV-2 transmission associated covariance coefficients to determine with the social determinants of health each city’s heterogeneity by each social could help the development of effective determinant (income, education, housmitigation strategies that are responsive ing density and proportions of visible to local transmission dynamics. This minorities, recent immigrants and study aims to quantify social determiessential workers). We visualized hetnants of geographic concentration of erogeneity using Lorenz (concentraSARS-CoV-2 cases across 16 census met-tion) curves. ropolitan areas (hereafter, cities) in 4 Canadian provinces, British Columbia, Results: We observed geographic con-Manitoba, Ontario and Quebec. centration of SARS-CoV-2 cases in cities, as half of the cumulative cases were Methods: We used surveillance data on concentrated in DAs containing 21%–confirmed SARS-CoV-2 cases and cen-35% of their population, with the greatsus data for social determinants at the est geographic heterogeneity in Ontario level of the dissemination area (DA). We cities (Gini coefficients 0.32–0.47), fol-calculated Gini coefficients to deter-lowed by British Columbia (0.23–0.36), mine the overall geographic hetero-Manitoba (0.32) and Quebec (0.28–geneity of confirmed cases of SARS-0.37). Cases were disproportionately concentrated in areas with lower income and educational attainment, and in areas with a higher proportion of visible minorities, recent immigrants, high-density housing and essential workers. Although a consistent feature across cities was concentration by the proportion of visible minorities, the magnitude of concentration by social determinant varied across cities.