When we visualize the epicenter of an outbreak, the mind conjures images of a densely populated cities. This seems logical because the chances of human contact and interaction are naturally much higher in these places.
Contrary to this popular assumption, such locations could be better equipped with superior medical facilities and systems to mitigate diseases on a large scale. Authorities in dense areas can easily enforce strong social distancing policies with more public awareness able to spread. Also, neighbors and family members can provide each other the much required emotional support while following sheltering-in-place policies.
According to a recent preliminary study conducted by Johns Hopkins Bloomberg School of Public Health, dense counties compared to well spread out ones have low rates of COVID-19 infection. That is possibly because populated areas tend to be more developed. Surprisingly, researchers found that when counties are economically and socially integrated with large metropolitan areas, they are more prone to suffering from pandemics.
The study led by Shima Hamidi, Bloomberg Assistant Professor of American Health in Environmental Challenges in the Department of Environmental Health and Engineering at the Bloomberg School
, was published in the Journal of the American Planning Association on June 18. The analysis included 913 metropolitan counties across the United States between Jan. 20 and May 25. It was performed through the Structural Equation Modeling approach, by balancing out demographic variables and health infrastructure.
When the researchers also calculated another measure known as “activity density,” which accounts for the density of both residents and workers in a particular location, it was found that infection rate of COVID-19 was not significantly high. Age, size, education and race as well as multiplying the activity density twice revealed that the death rate was lowered by 11.3 percent. Inversely, mortality rate in these regions with increased activity density was higher than expected.
“The fact that density is unrelated to confirmed virus infection rates and inversely related to confirmed COVID-19 death rates is important, unexpected, and profound. It counters a narrative that, absent data and analysis, would challenge the foundation of modern cities and could lead to a population shift from urban centers to suburban and exurban areas,” Hamidi said.
“Indeed, we find that pandemics are deadlier in low-density areas that have less access to quality health care. Our findings suggest that planners should continue to practice and advocate for compact places rather than sprawling ones due to several environmental, transportation, health, and economic benefits of compact development confirmed by dozens of empirical studies,” the study concluded.
The researchers will continue updating the data as the global health crises advances over the next few months. They are also in the process of putting together a longitudinal study on the relationship between county density and mortality rates.