Exploring the role of the social vulnerability index in understanding COVID-19 immunization rates

Communities that are historically marginalized and minoritized were disproportionately impacted by the COVID-19 pandemic due to long-standing social inequities. It was found that those who experience social vulnerabilities faced a heightened burden of COVID-19 morbidities and mortalities and concerningly lower rates of COVID-19 vaccination. The CDC's Social Vulnerability Index (CDC-SVI) is a pivotal tool for planning responses to health crises such as the COVID-19 pandemic. This study explores the associations between CDC-SVI and its corresponding themes with COVID-19 vaccine uptake in Nevada counties. Additionally, the study discusses the utility of the CDC-SVI in the context of equitable vaccine uptake in a pandemic setting. We examined the linear association between the 2020 CDC-SVI (including the composite score and the four themes) and COVID-19 vaccine uptake (including initial and complete vaccinations) for the seventeen Nevada counties. These associations were further examined for spatial-varied effects. Each CDC-SVI theme was negatively correlated with initial and complete COVID-19 vaccine uptake (crude) except for minority status, which was positively correlated. However, all correlations were found to be weak. Excessive vaccination rates among some counties are not explained by the CDC-SVI. Overall, these findings suggest the CDC-SVI themes are a better predictor of COVID-19 vaccine uptake than the composite SVI score at the county level. Our findings are consistent with similar studies. The CDC-SVI is a useful measure for public health preparedness, but with limitations. Further understanding is needed of which measures of social vulnerability impact health outcomes.