Not All Cities Are COVID-Equal

"I think we can safely say that certain drivers, such as a dense way of living, as well as age structure, in particular, the share of the population living in nursing homes, will strongly continue to predict worse [COVID] outcomes."
"What we find is that large metropolis are vulnerable mainly for two reasons. First, they are places with a dense way of life. Second, in large urban areas it is very hard to create a disease-free bubble because there is always inflow and outflow."
"Any epidemiological model of infectious disease will tell you that one of the most important drivers of the spread of the disease is the infection rate. Obviously that infection rate depends on how many other people an infected individual bumps into every day [and] that'll be much larger if I use the metro than if I live on an isolated farm in the countryside."
"Taken together, being connected to many other people makes you vulnerable. Ironically, what is very beneficial in normal times for the economy, makes you vulnerable in these abnormal times."
Klaus Desmet, economist, Southern Methodist University, Texas

The Toronto skyline on June 2. Photo by Peter J. Thompson / National Post

According to new research, certain cities become susceptible to the novel coronavirus infection rate much in excess of others as a result of complicating circumstances. In view of expectations of potential second and even third waves in the near future as SARS-CoV-2 reasserts itself, this research may be a critical tool for planning on the part of public health officials. Experts have been busy tracking the inexorable path of the coronavirus in view of the dread toll it has taken in Italy where close to 35,000 people lost their lives from its dread effects.

Germany, on he other hand experienced a quarter of the deaths that hit Italy, while New York City suffered the agony of experiencing the absolute worst global outbreak even as Los Angeles' death toll came out one-sixth the size of New York's. The greater Toronto and Montreal areas in Canada have accounted for over 66,000 of the approximately 100,000 cases in the entire country. According to Dr. Desmet, Canada's largest two cities' plight could be attributable to the very same forces that struck New York City, leaving it with a massive death toll.

A patient is transferred from Elmhurst Hospital in New York, US, on April 25, 2020. Elmhurst Hospital Trauma Center In Queens Borough of New York City Continues Receiving Covid-19 Patients. (John Lamparski/NurPhoto via Getty Images)

A city's density represents a factor of huge proportions in the incidence of COVID transmission, with other factors such as population age, and distance to an international airport; all characteristics that the two economists posit are most likely to define the occurrence of future outbreaks. From their study it seems clear to them that waves of the disease will not necessarily hit all cities in an equal manner; leaving some cities to cope with persistent outbreaks and other will be left in a relatively unscathed state.

Should this hypothesis bear out with future incidences validating the proposed trend, health experts and municipal authorities will be able to aim their resources in those areas identified with the greatest susceptibility, confident that other areas will not become vulnerable in their turn to similar-sized outbreaks. Those areas less affected will have little need to impose stringent lockdowns and can confidently anticipate earlier reopenings without fear of overwhelming their health-care system.

Density levels come most readily to mind when weighing the susceptibility to infection of any city. Verified by a glance at the statistics identifying North America's most population-dense cities with heavy outbreaks of COVID-19. Several features of density were considered in the study; the share of individuals living in multi-unit housing structures, and the number of people representing each household, along with a breakdown of occupancy per square kilometre.

Multi-unit housing and the size of households are both recognized to be positively associated with cases and death levels; a primary feature of any future outbreak. Places with more people using public transit have worse COVID-19 outcomes, and more so in terms of the death rate. There was a clear correlation found in the United States between the distance of a city to the international airport serving it, and an early COVID-19 outbreak.

Higher infection rates were seen to be clustered around Toronto's international airport. Peel Region, home to Pearson International Airport, saw a rate of 328 cases each 100,000 population, representing one of the highest rates in Ontario, second to the city of Toronto itself, with 394 cases per100,000 people. In Calgary, where the airport remained open to international flights, infection rates were much higher than what Edmonton experienced, which has a considerably smaller airport located a further distance from the city, and not open to international travel.



Researchers discovered the more people over the age of 75 the more likely for fewer cases to emerge, the reasoning being that younger people are likelier to search out activities that tend to spread the virus, such as large social gatherings and events. In some situations, an older population, however, can lead to greater death numbers, when considering outbreaks at nursing homes where social isolation, an immune-hampered and chronic health-vulnerable population surrenders to a demonically dangerous virus.

And then there is the perennial issue of poverty, its associated poor health outcomes in indigent communities and unequal access to health services with their bearing on mortality rate for all reasons including COVID-19. Outbreaks were identified in Black and Indigenous and Hispanic communities with higher infectious rates. What the conclusion of the study seemed to point out is that many of the activities that make for a well-adjusted social community are those that now place people at an increased risk of diminished health and possibly death.


"This should come as no surprise: as with any other infectious disease, contact between susceptible and infected individuals is a key determinant of the spread of the disease."
"There is a randomness in locations that got the virus early. One important exception is the variable capturing distance to international airports with connections to the top five COVID incidence countries as of March 15."
"Places with a large share of retired individuals may feature fewer places [bars, stadiums] where the disease spreads rapidly."
"This finding [outbreaks at nursing homes with high death rates] is consistent with the idea that once a county is affected by the pandemic, its nursing homes can quickly become powder kegs, and account for larger shares of countrywide deaths."
"Overall, these results confirm concerns that the COVID-19 pandemic has a disparate effect on various racial groups."
Study Report: Economists Klaus Desmet and Romain Wacziarg, University of California, Los Angeles  Study on COVID numbers in large cities: Report