Social inequalities and the early provision and dispersal of COVID-19 vaccinations in the United States: A population trends study

Abstract

Background: In December 2020 the U.S. began a massive COVID-19 vaccination campaign, an action that researchers felt could catalyze inequalities in COVID-19 vaccination utilization. While vaccines have the potential to be accessible regardless of social status, the objective of this study was to examine how and when socioeconomic status (SES) and racial/ethnic inequalities would emerge in vaccination distribution.

Methods: Population vaccination rates reported at the county level by the Centers for Disease Control and Prevention across 46 states on 3/30/2021. Correlates included SES, the share of the population who were Black, Hispanic, Female, or aged ≥65 years, and urbanicity (thousands of residents per square mile). Multivariable-adjusted analyses relied on zero-inflated negative binomial regression to estimate the odds of providing any vaccine, and vaccination rate ratios (aVRR) comparing the distribution rate for vaccinations across the U.S.

Results: Across the U.S., 16.3 % of adults and 37.9 % of adults aged 65 and older were vaccinated in lower SES counties, while 20.45 % of all adults and 48.15 % of adults aged 65 and older were vaccinated in higher SES counties. Inequalities emerged after 41 days, when < 2 % of Americans were vaccinated. Multivariable-adjusted analyses revealed that higher SES was associated with improved vaccination distribution (aVRR = 1.127, [1.100-1.155], p < 1E-06), while increases in the percent reporting Black or Hispanic race/ethnicity was associated with lower vaccination distribution (aVRR = 0.998, [0.996-0.999], p = 1.03E-04).

Conclusions: Social inequalities in COVID-19 vaccines reflect an inefficient and inequitable distribution of these technologies. Future efforts to improve health should recognize the central role of social factors in impacting vaccine delivery.

Keywords: COVID-19; Immunization disparities; Pandemic response; Race/ethnicity; Social epidemiology; Social inequalities; Social inequality; Socioeconomic status; Vaccination; Vaccine.

Fig. 1.

Geographic Distribution of Vaccination among individuals aged ≥65 stratified by U.S. County. Darker green show areas with coverage further above 70 % coverage. Darker orange shows counties with coverage under 70 %. Areas that appear whiter show regions where coverage is close to 70 %, the U.S. average on the date shown. Data from 3/30/2021 shown for comparison purposes. Gray areas lacked information about vaccination.

Fig. 2.

Trends showing average vaccination uptake among U.S. residents aged 12 and older throughout the U.S. (black solid line). Additional lines show trends stratified by socioeconomic tertile (the lowest SES tertile: short dashes with orange coloring, the average SES tertile is gray-blue lines with medium dashes, and the highest SES tertile is long dashes with black line).

Fig. 3.

Trends showing vaccination uptake in U.S. counties, separated by racial/ethnic composition: White (solid), %Black > 10 % (long dashes), % Hispanic > 10 % (short dashes), both % Black and %Hispanic > 10 % (dots).