Disparities in SARS-CoV-2 Positivity Rates: Associations with Race and Ethnicity

Abstract

Numerous reports indicate that African Americans and Latinos are being affected disproportionately by coronavirus disease 2019 (COVID-19). Positivity rates have not been analyzed on scale because only 4 states report race/ethnicity as part of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing. Previous studies also have had little ability to control for many known risk factors to better identify the effects of COVID-19 on racial and ethnic communities. Using test results from a large national reference laboratory database that included patients from all 50 states and the District of Columbia, this study compared positivity rates for SARS-CoV-2 nucleic acid amplification tests (NAAT) among various race/ethnicity groups by linking zip code-based race/ethnicity proportions from US Census data. Analysis of 2,331,175 unique patients tested March-May 2020 demonstrated an increasing trend in SARS-CoV-2 NAAT positivity across Black non-Hispanic community progressive quintiles (from 7.8% to 17.2%, P < 0.0001) and Hispanic community progressive quintiles (from 8.4% to 15.5%, P < 0.0001) and a decreasing trend across White non-Hispanic community progressive quintiles (from 17.4% to 7.1%, P < 0.0001). These trends in viral ribonucleic acid positivity remained in stratified analyses and in multivariable models that controlled for known risk factors including sex, population density, and the states initially hardest hit by COVID-19. These findings indicate that communities with the highest proportions of Black non-Hispanic and Hispanic populations have the highest SARS-CoV-2 NAAT positivity rates, even after controlling for other risk factors. More efforts are needed to mitigate the increased impact of COVID-19 on both the African American and Hispanic communities.

Keywords: COVID-19; SARS-CoV-2; ethnicity; race.

FIG. 1.

COVID-19 positivity by race/ethnicity community quintiles. Quintiles were derived from analysis of race/ethnicity proportions as estimated by the US Census Bureau (2018 American Community Survey 5-Year Estimates). Cochran-Armitage test for trend, P < 0.0001 for each race/ethnicity group.

FIG. 2.

COVID-19 positivity by race/ethnicity community quintiles in the most and least densely populated areas. Quintiles were derived from analysis of race/ethnicity proportions as estimated for each zip code by the US Census Bureau (2018 American Community Survey 5-Year Estimates). Population density quintiles were derived from analysis of each zip code by the US Census Bureau (2010 Census). Cochran-Armitage test for trend, P < 0.0001 for all groups except Asian non-Hispanic in least densely populated areas (not significant).

FIG. 3.

COVID-19 positivity by race/ethnicity community quintiles in the highest and lowest income areas. Quintiles were derived from analysis of race/ethnicity proportions and mean income as estimated for each zip code by the US Census Bureau (2018 American Community Survey 5-Year Estimates). Cochran-Armitage test for trend, P < 0.0001 for all groups.