States With More Insured Residents Have Higher COVID-19 Vaccination Rates

The COVID-19 vaccine is free for all, but as Sarah Kliff writes in the New York Times, a recent Kaiser Family Foundation poll found that “about a third of unvaccinated adults were unsure whether insurance covered the new vaccine and were concerned they might need to pay for the shot.” This raises the question of whether state variation in COVID vaccination rates is due in part to state-level differences in the percentage of residents with health insurance and state policy decisions that influence the availability and quality of health insurance.

The figure below shows the relationship between state vaccination rates as of May 30, 2021 and state health insurance rates. Both rates are for adults 18 and over. The health insurance data is for 2019, the most recent year available. As the figure below shows, states with higher rates of insured residents generally have higher COVID-19 vaccination rates.

Fourteen states have yet to adopt or implement the Affordable Care Act’s Medicaid expansion for low-income adults, despite a large body of research finding that it “has expanded coverage and led to increases in access and utilization to health care services, improvements in financial security and positive net effects for state budgets and revenues.” The average full vaccination rate for adults across these states is about 8 percentage points lower than it is across the states that have expanded Medicaid.

Of course, a much more sophisticated analysis than this will be required to understand state variations in COVID-19 vaccination rates. But these results, combined with the Kaiser poll and Kliff’s reporting, suggest that the inability to pay for or the lack of insurance, medical debt, or past experiences with surprise medical bills explain at least some of it.

This first appeared on CEPR.