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Residents of Los Angeles can go to a county website to look up how many confirmed coronavirus cases there are in Beverlywood, or Koreatown, or Echo Park. Officials in Charlotte, North Carolina, have released figures at the ZIP code level. The South Korean government is sending geotargeted texts to alert citizens to positive cases near them.

In New York, now at the center of the outbreak, Mayor Bill de Blasio has resisted releasing what the city knows about a basic question: Where, precisely, is the virus?

Answers could take the form of a number of data points — tests, confirmed infections, hospitalizations or deaths — each of which shed light on a different part of the crisis.

Instead New York, along with several other state and county governments around the country, has released daily data only on the county, or borough, level. That means there is just one figure for COVID-19 cases in all of Kings County — Brooklyn — which has a population larger than 15 states. The roughly 4,600 confirmed COVID-19 cases among Brooklyn’s 2.6 million residents account for 8% of the confirmed cases in the entire country. There is also just one coronavirus case figure for the 2.2 million residents of Queens, where there are just over 5,000 confirmed cases.

The lack of detailed information makes it difficult for medical workers, journalists and the public to establish whether particular communities in the city are being harder hit and to get beyond anecdotal accounts of which of the city’s roughly 60 hospitals are already overwhelmed.

Dr. Michael Augenbraun, director of the infectious diseases division at SUNY Downstate Medical Center in central Brooklyn, said that while he knows the city has its hands full, the data could be useful for doctors. “Everyone is struggling to make sense of this evolving picture,” he said. “I think it would be useful to us in the hospitals to get a detailed situational appraisal, to know how much of the burden we are confronting.”

Augenbraun noted that more precise data could reveal important trends in how the disease is affecting different New Yorkers. “There are many things that may correlate with the spread of infectious diseases,” he said. “Race might be one, poverty might be another.”

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But some of those same factors, particularly ethnicity and race, may account for the city’s reluctance to make public more localized data that could point to clusters in particular neighborhoods, among certain communities. Around the country, there have been disturbing reports of bias attacks against Asian Americans by assailants blaming Chinese communities for the spread of the virus.

“The risk is that certain communities would be unfairly stigmatized, especially if communities with many COVID-19 cases already shoulder poverty or high crime,” said Dr. Jessica Justman, associate professor of medicine in epidemiology at Columbia University. “On the other hand, communication and information are always important and especially important in a pandemic setting.”

Some experts argue that the city should be releasing more granular information, perhaps even down to the block level.

“More detailed information will allow everyone to target their efforts much more effectively than only county-level information,” said John Mollenkopf, director of the Center for Urban Research at the CUNY Graduate Center.

In Newark, the largest city in neighboring New Jersey, Mayor Ras Baraka has disclosed that there were three coronavirus hot spots where residents should take extra precautions. On March 21, the city released detailed maps of the areas, which cover between 50 and 100 square blocks; it did not release the specific number of cases for each area.

New York has held fast on the policy the mayor laid out during a March 12 press conference when he was asked by a reporter if the city could go beyond borough-level numbers and break down cases by neighborhoods. The mayor declined, saying only that the city would release figures in the case of what he called a “cluster.”

“When we say ‘community spread,’ the assumption should be that this is something that is going to reach every corner of the city, whether we like it or not,” he said at the press conference. “And I don’t think it’s particularly productive. I don’t know what you do with that information. I don’t know how you change your life. Unless there is an indication of a cluster, that’s something we absolutely will talk about.”

New York City is the most densely populated major city in the United States, where the boroughs are counties unto themselves and would rank among the most populous cities in the U.S. if taken separately.

Sitting next to de Blasio at the March 12 press conference, Dr. Raul Perea-Henze, the deputy mayor for health and human services, said there was “another piece” to raise in response to the data question. “We need your help with the stigma this is generating,” he said. “We hear of real serious consequences of people that have been singled out over the course of the past weeks.”

When de Blasio made those remarks two weeks ago, there were just 95 confirmed cases in the city. There are now over 16,000. ProPublica asked the mayor’s office if there are “clusters” of the virus yet, or if the city has stopped looking for clusters now that the disease is so widespread. Avery Cohen, deputy press secretary for the mayor’s office, responded, “Given the extent of community transmission, clusters are not applicable to this situation.”

Asked why the city is only releasing data at the borough level, NYC Department of Health and Mental Hygiene spokesman Michael Lanza said in a statement to ProPublica: “As this evolves, we are presenting new information to the public daily. Some data will take longer to compile, collect and present including patient- and hospital-level information.”

It’s clear the city is collecting at least some demographic data about COVID-19 patients: Its daily releases already break down cases by age and sex. It also has long released detailed information about patients with influenza-like symptoms.

When patients visit emergency departments at hospitals in New York City, an admission clerk or nurse will document the primary reason for their visit, including their symptoms. This real-time data is sent to the city’s Health Department to be analyzed for health trends like flu patterns, a process that is also known as syndromic surveillance. The public data that the city publishes is available at the ZIP code level. There is also a map of influenza-like illness clusters on the city Department of Health’s website and an option to “analyze by neighborhood.” However, it’s unclear at this point how closely COVID-19 diagnoses align with the syndromic data.

Denis Nash, a professor of epidemiology at CUNY School of Public Health, said he believed the city might be reluctant to release more data because of concern about stigma. “There has been a documented outbreak in Hasidic communities in New York state; my guess is that if they released the data it might highlight something more that could create tension where people could be discriminated against,” he said. There was reportedly an early spike of positive cases in two Brooklyn neighborhoods with large Hasidic communities, Williamsburg and Borough Park.

Read More Are Hospitals Near Me Ready for Coronavirus? Here Are Nine Different Scenarios. How soon regions run out of hospital beds depends on how fast the novel coronavirus spreads and how many open beds they had to begin with. Here’s a look at the whole country. You can also search for your region.

Given New York’s density, another concern could be that neighborhood-by-neighborhood data “could give people a false sense that it’s happening there, but not here,” said Janet Hamilton, senior director of policy and science at Council of State and Territorial Epidemiologists. The most important goal, she said, is “trying to help people understand that they are at risk and there is very active transmission in the city.”

The state of New York is releasing information on the number of confirmed cases county-by-county. Asked if more is available, a spokesperson for the state Department of Health said, “The information on our website is the information currently available.”

De Blasio has also declined to release information about hospital bed capacity. Asked at a press conference March 20 whether the city could release that data, the mayor demurred. “That’s a conversation I want to have internally before I make a specific commitment to you,” he said.

Detailed information about COVID-19 hospitalizations could, in theory, help the public assess difficult decisions authorities are making about how to distribute scarce resources such as ventilators and protective gear around the city. At a press conference on Tuesday, de Blasio announced that roughly 2,000 ventilators were on their way from the federal government, but that the city still has nowhere near the 15,000 ventilators it expects to need. Access to these critical supplies is “going to be the difference between life and death for thousands upon thousands of New Yorkers,” he said.

Around the country, what data is emerging varies considerably from state to state and county to county.

In Washington, the state with the first confirmed case of the novel coronavirus, the public health agency for Seattle and the rest of King County produces daily updates of cases countywide, and in some instances, the medical facility where the person died. Westchester, just north of New York City, was identified as a hot spot early on. There, County Executive George Latimer released figures for the 10 cities and towns with the most positive cases. The Florida Department of Health created an interactive map covering the state along with a daily update that lists the infections in each city, among other details.

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