A study today in JAMA Network Open details US county-level COVID-19 infection and death inequities based on racial composition and income in the first 200 days of the pandemic, adding to mounting evidence of disproportionate burdens among racial minorities and those of lower income levels.
Researchers from University of Illinois at Urbana-Champaign and DePaul University analyzed data from seven US agencies and organizations on all but 1 of 3,142 counties in 50 states and Washington, D.C. from Jan 22 to Aug 8. They found that a 1.0% increase in a county's income inequality was associated with a 2.0% increase in COVID-19 infection and a 3.0% rise in related deaths.
An increase of 1.0% in a county's black population was associated with a 1.9% increase in coronavirus infection and a 2.6% rise in related deaths. Similarly, a 1.0% increase in a county's Hispanic population was linked to a 2.4% rise in infections and a 1.9% increase in related deaths.
The interaction between county black population and income disparities was not as strong as that between Hispanic composition and income inequality. But income inequity was most strongly linked to higher COVID-19 infection rates in counties with relatively low black or Hispanic populations.
In counties with high levels of income inequality, the link between estimated coronavirus death rate and black population remained positive, but it was negligible between estimated death rate and Hispanic composition.
Medicaid expansion, fewer infections
After controlling for state-level factors, state politics (governor sex, political affiliation, and term limit) weren't tied to coronavirus infection or death rates, but the COVID-19 infection rate in counties in states with Affordable Care Act expanded Medicaid eligibility was, on average, 32% lower than in counties that did not participate in Medicaid expansion. However, Medicaid expansion was not tied to a difference in coronavirus death rates.
Among all counties, black residents made up a mean of 9.37% of the population, while Hispanics accounted for 9.75%. On average, the number of confirmed COVID-19 cases per 100,000 people was 1,093.88 (range, 0 to 14,019.85), and the mean number of coronavirus-related deaths was 26.17 per 100,000 people (range, 0 to 413.86).
The authors noted that counties with a higher proportion of black or Hispanic residents and those with higher levels of income inequality were associated with higher rates of COVID-19 infections and deaths. But they said that while racial and ethnic composition is important, income differences also contribute to coronavirus health disparities.
"High levels of income inequality harm population health (indicated by high levels of COVID-19 incidence and mortality), irrespective of racial/ethnic composition," they wrote.
The researchers concluded by calling for "a dedicated commitment to dismantling structural racism and economic inequality, particularly racialized economic inequality."