Patterns and mediators of racial and ethnic disparities in COVID-19 vaccine hesitancy among young adults.

COVID-19 vaccines have been available for over a year, yet 26% of U.S. young adults remain unvaccinated. This study examines racial and ethnic disparities in young adult vaccine hesitancy and attitudes/beliefs that mediate disparities in vaccine hesitancy. Young adults (n = 2041;Mean[SD]:21.3[0.7] years-old) from a Los Angeles, CA, USA cohort were surveyed online in January-May 2021 and classified as vaccine hesitant (those who reported "Not at all likely"/"Not very likely" /"Slightly likely" to get vaccinated) versus non-hesitant (those who reported "Moderately likely"/"Very likely"/"Definitely likely" to get vaccinated or already vaccinated). Multivariable logistic regression was performed to examine racial/ethnic disparities in vaccine hesitancy. Factor analysis was conducted to create three subscales toward vaccination: positive, negative, and lack-of-access beliefs. Mediation analyses were performed to assess pathways from attitude/belief subscales to racial disparities in vaccine hesitancy. Overall 33.0% of respondents reported vaccine hesitancy. Black vs. White young adults had a higher prevalence of vaccine hesitancy (AOR[95%CI] = 4.3[2.4-7.8]), and Asians vs. Whites had a lower prevalence (AOR[95%CI] = 0.5[0.3-0.8]). Mediators explained 90% of the Black (vs. White) disparity in vaccine hesitancy, including significant indirect effects through positive belief-reducing (β = 0.23,p < .001) and negative belief-enhancing (β = 0.02,p = .04) effects. About 81% of the Asian (vs. White) disparity in vaccine hesitancy was explained by the three combined subscales, including significant positive belief-reducing (β = -0.18,p < .001) indirect effect. Substantial racial and ethnic disparities in young adult COVID-19 vaccine hesitancy were found, which were mediated by differences in attitudes and beliefs toward vaccination. Targeted education campaigns and messages are needed to promote equitable utilization of the effective vaccine.