Public health interventions, more hospitals associated with reduction in COVID-19 case-fatality rates

Counties that banned in-person religious gatherings and those with a greater number of hospitals per capita were associated with a decreased case-fatality rate of COVID-19 during the pandemic’s first wave, according to a new University of Michigan study.

On the other hand, counties with high prevalence of asthma and a greater concentration of people over 65 were linked to higher fatality rates, the analysis showed.

This study, published in PLOS ONE, was completed as part of the COVID-19 Dispersed Volunteer Research Network and was presented at the World Microbe Forum, a collaborative virtual meeting conference hosted by the American Society for Microbiology and the Federation of European Microbiological Societies, earlier this year.

Our work provides insights that may help officials target public health interventions and health care resources to locations that are at increased risk of COVID-19 fatalities in subsequent waves.”

Jess Millar, graduate research assistant, U-M departments of Computational Medicine and Bioinformatics, and of Epidemiology

Millar and colleagues looked at public data from 3,000 counties to do the risk factor analysis of demographic, socioeconomic and health-related variables during the first wave of the pandemic (March 28 to June 12, 2020). The case-fatality rate was defined as the number of deaths divided by the total number of confirmed COVID-19 cases.

Researchers found a reduction in case-fatality rates of:

• 32% per additional hospital per 10,000 people
• 13% if religious gatherings were banned
• 1.5% per 1% increase in the proportion of population without health insurance
• 0.79% per 1% increase in the proportion of mobile homes

They saw an increase in case-fatality rates of:

• 9.5% per 1% increase in asthma prevalence
• 4.5% increase per 1% increase in population over age 65
• 3.2% per one additional hospital
• 0.97% per 1% increase in Black or African American population