Racial/Ethnic Disparities In COVID-19 Exposure Risk, Testing, And Cases At The Subcounty Level In California

Abstract

With a population of forty million and substantial geographic variation in sociodemographics and health services, California is an important setting in which to study disparities. Its population (37.5 percent White, 39.1 percent Latino, 5.3 percent Black, and 14.4 percent Asian) experienced 59,258 COVID-19 deaths through April 14, 2021-the most of any state. We analyzed California's racial/ethnic disparities in COVID-19 exposure risks, testing rates, test positivity, and case rates through October 2020, combining data from 15.4 million SARS-CoV-2 tests with subcounty exposure risk estimates from the American Community Survey. We defined "high-exposure-risk" households as those with one or more essential workers and fewer rooms than inhabitants. Latino people in California are 8.1 times more likely to live in high-exposure-risk households than White people (23.6 percent versus 2.9 percent), are overrepresented in cumulative cases (3,784 versus 1,112 per 100,000 people), and are underrepresented in cumulative testing (35,635 versus 48,930 per 100,000 people). These risks and outcomes were worse for Latino people than for members of other racial/ethnic minority groups. Subcounty disparity analyses can inform targeting of interventions and resources, including community-based testing and vaccine access measures. Tracking COVID-19 disparities and developing equity-focused public health programming that mitigates the effects of systemic racism can help improve health outcomes among California's populations of color.

Exhibit 3:. Relationship Between Household Exposure Risk, Test Rate, and Test Positivity Rate

SOURCE Authors’ analysis of data from the American Community Survey and the California Department of Public Health. NOTES Outcomes span March 22 to October 3, 2020. Month–specific results are located in the Appendix. Colors show quartiles of testing rates. Each circle shown represents one of California’s PUMAS. To improve visualization, household exposure risk was capped at 30%.

Exhibit 4:. Test Positivity Rate by Race/Ethnicity and Household Exposure Risk

SOURCE Authors’ analysis of data from the American Community Survey and the California Department of Public Health. NOTES Outcomes span March 22 to October 3, 2020. Each circle shown represents the racial/ethnic-specific subpopulation of one of California’s PUMAs. Month–specific results are located in the Appendix.