In the first two and half months of Covid-19 vaccine distribution in the US, counties considered to have high social vulnerability had lower vaccine coverage than counties considered to have low social vulnerability, according to a study published Wednesday by the US Centers for Disease Control and Prevention.
The CDC social vulnerability index identifies communities that may need additional support during emergencies based on 15 indicators across four categories: socioeconomic status, household composition, racial/ethnic minority status and housing type. Counties were split equally between high, moderate and low social vulnerability.
By March 1, nearly 52 million vaccine doses had been administered in the US, and about 15.1% of the population had received at least one dose. But vaccination coverage was about 2 percentage points higher in counties with low social vulnerability (15.8%) than in counties with high social vulnerability (13.9%). The differences were largely driven by socioeconomic disparities, particularly differences in the share of the population with a high school diploma and per capita income.
Only five states – Arizona, Montana, Alaska, Minnesota and West Virginia – had higher coverage in counties with high social vulnerability than in counties with low social vulnerability based on the overall index.
Best practices in these states included prioritizing racial/ethnic minority groups in early vaccine coverage, actively monitoring barriers to vaccination, directing vaccines to vulnerable communities, offering free transportation to vaccination sites and collaborating with community partners and tribes, according to the study.
The CDC says that achieving vaccine equity – not just equality – is an important goal, requiring “preferential access and administration to those who have been most affected” beyond proportionate distribution based on population.
Despite disproportionate incidence of Covid-19 among non-English speaking communities and people with a disability, equal vaccination coverage was observed in these metrics for communities with both high and low social vulnerability.
Also, higher coverage in counties with larger shares of older adults is consistent with prioritization strategies. But disparities linked to access to a vehicle were “unexpected and warrants further investigation,” according to the CDC.
The CDC social vulnerability index does not include all factors that may be used to identify disparities. Internet access, for example, is not measured. Also, population-based measures do not assess individual-level vulnerability, and vulnerabilities may vary within counties. Finally, vaccine priority groups varied by state, which may drive some differences.