Are New Yorkers at greater risk of catching coronavirus?

New York state recorded its first case of the coronavirus over the weekend, bringing the disease that’s rapidly spread in countries including China, Iran and Italy to the Empire State. And while Gov. Andrew Cuomo and New York City Mayor Bill de Blasio convened on Monday to assure New Yorkers that they should carry on with business as usual, stranghangers can be seen holding onto subway poles with their shirt sleeves and wearing face masks on the subway.

It would seem that the subway, with its teeming masses, and the streets of Manhattan or crowded stores and restaurants throughout New York City are especially risky places when there’s a deadly virus on the loose. But how much risk are New Yorkers really exposed to in comparison to their counterparts in more spread-out, car-dependent areas?

City & State looked into whether New Yorkers – or others living in dense urban areas – are at higher risk of contracting diseases like the coronavirus or the common cold or flu because of how densely populated the area is. But before wishing you could drive to work or live in a single-family home where hundreds of people aren’t touching the same doorknobs every day, have a look at what the experts have to say. Viruses may spread more quickly in dense environments like New York City, but that’s not the only determinant of risk of transmitting disease.

When it comes to diseases that we catch from other people, it’s probably not surprising that viruses tend to spread more quickly in a place like New York City, with a population density of over 27,000 people per square mile, than in an upstate town like Rotterdam, New York, which has a population density of roughly 3,000 people per square mile. “In general, infections with person-to-person transmission, such as this coronavirus and flu, often will spread more rapidly in denser urban environments,” Dr. Stephen Morse, professor of epidemiology at Columbia University’s Mailman School of Public Health, wrote in an email on Monday.

Dr. Robyn Gershon, a clinical professor of epidemiology at New York University’s School of Global Public Health pointed to a 2015 study in Infection Ecology and Epidemiology that found high population density and close contact between people could make cities hotbeds for rapid spread of infectious diseases like severe acute respiratory syndrome (SARS) and the avian flu. Though the New York City subway may be a hot bed for viruses – not the new coronavirus in particular, but all kinds – regular riders can also build up immunity after being exposed to the same viruses. With a situation like the new coronavirus, however, New Yorkers haven’t had a chance to build immunity. 

So do inner-city subway and bus riders typically get sick more often than suburbanites and small-town residents? There’s not a lot of research directly comparing the two groups, but one study by the University of Nottingham in the U.K. found that public transit riders are six times more likely than those who didn’t ride public transit to have acute respiratory infections, but that occasional riders were more at risk than everyday riders because the latter group may build up immunity. On the other hand, a 2011 study in the Journal of Urban Health that simulated a 1957-1958 influenza pandemic in New York City found that only 4% of transmissions would occur on the subway.

But while infectious diseases might spread more rapidly in urban areas, that doesn’t mean New Yorkers are doomed to contract every infectious disease in the book. Morse noted that other factors – chance, the precautions people may take – also come into play. In the case of the novel coronavirus, for example, public health experts are advising people to practice good regular hygiene by washing their hands and not touching their faces. 

As anyone who has ever lived in the suburbs or rural areas knows, city dwellers don’t own the flu or the common cold. “Even in the suburbs, there are many places where people may congregate in numbers – many workplaces, schools, shopping malls, movie theaters, sports events, for example, so there is potential for spread there as well,” Morse told City & State. Some public health experts, in fact, have said that running into viruses or bacteria on the subway isn’t any likelier than in other environments, such as offices. 

Suburban areas, of course, also often have public transit systems, though they’re not as widely used as in New York. 

New Yorkers may also benefit from something else that rural areas tend to lack: a good public health system. “I’ve seen studies (showing) that people in vibrant, high-income, developed-nation urban areas have much better access to health care,” Gershon said. “People in rural areas have a much harder time getting access to emergency care like ambulances, and then once they’re in that ambulance, it can be a very long drive to the hospital.” Still, New York’s hospitals have room for improvement, and some have received low rankings from the federal government.

At a joint press conference on Monday, Cuomo and de Blasio urged New Yorkers to stay calm, while at the same time acknowledging what’s been clear since the coronavirus first became widespread – it would eventually come to New York. While the coronavirus is reported to be highly transmissible, it comes from prolonged contact with an infected person, not just brushing past someone on a crowded subway car. “We should relax, because that's what's dictated by the reality of the situation,” Cuomo said, while also encouraging individuals to practice vigilant personal hygiene and to seek care if they exhibit symptoms.

Representatives for New York City Health Commissioner Dr. Oxiris Barbot did not respond to a request for comment on Monday. The Metropolitan Transportation Authority said last week that it has been monitoring the situation every morning and seeking updates from federal, state and city health officials.