Hong Kong, by some measures the world’s densest city—and situated just 571 miles away from Wuhan—has so far suffered only four deaths from the Covid-19 pandemic. The cities of Macau, Singapore, Taipei, and Tokyo—all dense and proximate to China—have also managed to keep coronavirus deaths and cases in check. Meantime, in New York City, headlines proclaim density as the city’s “big ‘enemy.’” But urban history shows that fighting outbreaks rests on good governance, coupled with strong social norms that protect vulnerable people.

Cities are, by definition, the “absence of physical space between people,” as Harvard economist Edward Glaeser describes them. Their success depends on the face-to-face contact now perilous to our health. Contagion turns the logic of cities on its head. “If you’re close enough to share an idea,” observes Glaeser, “you’re close enough to spread a contagious disease.” Yet, for many in New York, the city is their living room. They live cheek-to-jowl with some 28,000 people per square mile because of the city’s amenities and opportunities. Now everything is shuttered and perilous in America’s densest urban center.

Throughout history, cities suffered from bouts of congestion, crime, and scarce housing. But the greatest demon of density was disease. In the nineteenth century, cities made enormous investments in infrastructure and regulation to cast out the contagions that created “population sumps.” By 1900, nearly half of all deaths in America’s major cities were still caused by infectious illnesses. Yet, in part because cities spent as much on supplying their residents with clean water, writes Glaeser, “as the federal government was spending on everything except the post office and the army,” by the late 1930s, fewer than one in five urban deaths in America was attributed to infectious disease.

Yet diseases adapt, while cities like New York have not, at least so far. Covid-19 is ruthlessly exploiting new vulnerabilities that have emerged over the past century, whether it’s the 140 million passengers per year traveling through New York’s airports or the more than 5.6 million riders cramming into the city’s subway cars on a typical workday. Expensive housing forces roommates to share ever-more cramped quarters. Such forced proximity heightens risks for infection—unless a city is prepared.

During the 2003 SARS outbreak, nearly 300 people died in Hong Kong, second only to mainland China. Forty-two people died in a single Hong Kong apartment complex. The experience resulted in “deep psychological scars” that transformed how Hong Kong, as well as other affected Asian cities, handled public health. Within days of China’s announcement last December 31 of an “unknown viral pneumonia” in Wuhan, Hong Kong began conducting temperature checks at border crossings, restricting travel from China, and quarantining and tracing contacts for confirmed cases of what became known as Covid-19. By the end of January, all schools and universities were closed, and mass gatherings were cancelled; teleworking commenced. The vast majority of Hong Kongers had already worn face masks and practiced social distancing for weeks.

A similar picture of fast-acting governments and healthy social norms emerges in Singapore, where deaths from Covid-19 can so far be counted on two hands, and Macau, which has reported no deaths. Macau was the first city outside mainland China to engage in a total lockdown, even of its famed casinos, which account for 80 percent of its tax revenues. Meantime, Singapore was the first to ban incoming flights from Wuhan and to quarantine travelers from infected countries. Temperature checks outside nearly every building and restaurant in the island city-state kept many businesses and nearly all its schools open until this week. By quarantining vulnerable populations and adopting strict contact tracing, these dense cities could maintain remarkably normal day-to-day life. Though even now, their relative success is being threatened by failures to contain Covid-19 in Europe and the United States.

Life isn’t normal in New York or for the three-quarters of Americans currently under lockdown. New York has the largest numbers of cases and deaths from Covid-19 of any city in the world, but smaller, less dense cities like New Orleans (32.7 deaths per 100,000) and Albany, Georgia (56.6 deaths per 100,000) suffer from similar or higher death rates than Gotham metro (33.8 deaths per 100,000). New Orleans was hit particularly hard after failing to cancel Mardi Gras. The city, with just 0.1 percent of the national population, accounts for more than 3 percent of America’s Covid-19 deaths, as of April 7. In the pandemic’s early stages, outbreaks occurred in suburbs like Kirkland, Washington and New Rochelle, New York, but the virus has since preyed on poorer, working-class neighborhoods like Corona in Queens or on tightly knit communities, such as among Hasidic Jews in Brooklyn’s Borough Park.

It turns out that population density isn’t the key determinant of a city’s susceptibility to Covid-19. Outbreaks correlate instead with preexisting health problems, social norms, and the quality of governance. Disease prevalence also tracks with rates of tourism and recreational amenities, which rural areas also enjoy (their rates of infection are keeping pace with denser cities). Ironically, a large, dense city may be better equipped to fight infectious diseases. Cities typically have a higher concentration of hospitals, medical professionals, and public-health officials. In addition, they foster strong norms that, as smartphone tracking confirms, encourage the social distancing that can flatten the case-growth rate.

Public-health officials in Asian cities had long stockpiled critical medical equipment and introduced redundancies into hospital systems to reduce overload. City dwellers donned masks and embraced social distancing, adapting the norms and rules of city life in ways that the U.S. has only begun to adopt. Even as Covid-19 spread from “patient zero” in Washington State in mid-February, most American cities didn’t adopt stay-at-home orders until after mid-March.

Covid-19 sheds light not on the problems of density but on the deficiencies of our urban political leadership. Density is deadlier in the U.S. because of a lack of effective local governance, coupled with weak social norms. Urban America failed to protect susceptible populations in timely fashion, and thus failed to reduce transmissibility; the only available measures were draconian lockdowns that have worsened many cities’ fiscal condition. America’s growing death toll from this pandemic is the result of a slow government response, one rooted in the failures of our urban political class.

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