Measuring and Promoting SARS-CoV-2 Vaccine Equity: Development of a COVID-19 Vaccine Equity Index

Abstract

Purpose: The coronavirus pandemic has created the greatest public health crisis in a century, causing >500,000 deaths in the United States alone. Minoritized and socioeconomically disadvantaged groups have borne a disproportionate burden of severe illness, hospitalization, and death from COVID-19. Recently developed FDA-approved vaccines have been shown to significantly reduce severe COVID-19-related outcomes. Vaccination campaigns have the potential to advance health equity by prioritizing allocation to those at highest risk while striving for herd immunity. Large integrated health systems have been faced with the daunting task of meeting the rapidly evolving needs of diverse patient populations for the provision of population-based testing, treatment, education, and now vaccine distribution. We have designed a COVID-19 vaccine equity index (CVEI) to guide health system vaccination strategy. Methods: We considered proportion unvaccinated within a health care system. We then used real-time readily available electronic health record (EHR) COVID-19 testing positivity and proportion hospitalized to measure burden of illness by race/ethnicity. We used conditional probability and statistical theory to measure equity for unvaccinated individuals and to derive an index to highlight these inequities for specific subgroups. Results: We present an illustrative hypothetical example using simulated data for which we calculated the CVEI for non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, and Hispanic patients. In the example, non-Hispanic Black and Hispanic patients had inequitable outcomes. Conclusion: The index can be widely implemented to promote more equitable outcomes among racial/ethnic groups, reducing morbidity and mortality within the overall population as we pursue the collective goal of herd immunity through mass vaccination.

Keywords: COVID-19; COVID-19 vaccine equity index; SARS-CoV-2; health equity; vaccine equity.

FIG. 1.

Cascade of conditional probability of hospitalization with COVID-19. Illustration of sequential pathway: (1) unvaccinated to infected among the unvaccinated; (2) infected to hospitalized among the infected and unvaccinated.

FIG. 2.

Demonstration graph of equality and equity goals by race/ethnicity. Bar graph represents percentage vaccinated for each race/ethnicity. A goal for herd immunity of 70% is assumed. Dark blue markers represent goals for each race/ethnicity based on a vaccination strategy of equality. Light blue markers represent goals for each race/ethnicity based on a vaccine strategy of equity.