"All it needs is fertile soil because it spreads quite well, unfortunately."
The first sustained outbreak to be detected in the New York metropolitan area occurred in the suburb of New Rochelle, where a lawyer who had attended large gatherings at a local synagogue was the first to test positive.
Another cluster sprang up 8km west of the city in Teaneck, New Jersey. The first New Jersey resident to die, 69-year-old horse racing veteran John Brennan, lived in northern New Jersey and worked at a racetrack in Yonkers, a New York suburb.
According to data compiled by Johns Hopkins University, Rockland County, New York, has reported roughly 3500 positive cases per 100,000 residents, nearly triple the rate in Manhattan and more than double the rate in Brooklyn.
Westchester County, which includes New Rochelle, has a rate of nearly 2900 cases per 100,000 residents.
If the five New Jersey counties closest to New York were a country, they would have recorded the 12th most cases in the world, more than 59,000 to yesterday.
At Hudson Regional Hospital in Secaucus, New Jersey, just west of Manhattan, the volume of patients had quadrupled by early April, forcing the emergency room to divert patients several times, hospital CEO Dr Nizar Kifaieh said, though the numbers have decreased recently.
Dr Tanaya Bhowmick, an infectious disease physician and assistant professor at Rutgers Robert Wood Johnson Medical School in New Jersey, said her patients who have underlying immune issues have been taking precautions. But she recently saw a group of youths playing basketball in her suburban neighbourhood.
"There might be the perception that they're a little more safe here, which obviously isn't true," she said.
It wasn't surprising to Stamford Mayor David Martin that his Connecticut city of about 130,000 people would be hard hit.
Downtown Stamford is less than 16km from the New York state line and less than an hour from Manhattan by train. Nearly 1800 Stamford residents have tested positive for the coronavirus, by far the highest total among the state's 169 cities and towns.
"The reality is that ... in normal times we have 30,000 people get on or get off the train at the Stamford train station and a big chunk of those people are travelling to or from New York City," Martin said.
"With a wide diversity of socioeconomic status that are basically right here next to the New York epicentre, it has been a struggle for us."
Commuting patterns can partly explain the virus' spread in the New York region. Subway ridership in the city tops five million on an average weekday, and according to a recent study by the city's planning commission, about one million people travel into New York each day from the surrounding counties — and a quarter of a million go in the opposite direction — many on public transportation that is routinely overcrowded.
The picture is more complicated, though. An AP study of Covid-19 cases by zip code in New York City has found, for example, more cases per capita in Staten Island, the least congested of the five boroughs and the one not served by the city's subway system, than in some of the more densely populated areas of Manhattan, Brooklyn and Queens.
- AP