The testing results from the urgent-care company CityMD were shared with The New York Times.
At a clinic in Corona, a working-class neighborhood in Queens, more than 68 percent of people have tested positive for antibodies to the virus, suggesting that their immune systems had encountered an infection and responded to it. At a clinic in Jackson Heights, also in Queens, that number was 56 percent. But at a clinic in Cobble Hill, an affluent Brooklyn neighborhood, only 13 percent of people tested positive for antibodies.
While stopping short of predicting that hard-hit neighborhoods like Corona and Jackson Heights would be relatively protected in any major new outbreak — a phenomenon known as herd immunity — several epidemiologists said that the different levels of antibody prevalence were likely to play a role in what happens next, assuming that antibodies do, in fact, offer significant protection against future infections.
“Some communities might have herd immunity,” said Dr. Daniel Frogel, a senior vice president for operations at CityMD, which runs urgent-care centers throughout the metropolitan area and plays a vital role in the city’s testing program.
As the virus has swept through New York, it has exposed stark inequalities in nearly every aspect of city life, from who has been most affected to how the health care system tended to those patients. Many lower-income neighborhoods, where Black and Latino residents make up a large part of the population, were hard-hit, while many wealthy neighborhoods had far fewer cases.
But if there is a second wave of the virus, some of those vulnerabilities may flip, with the affluent neighborhoods becoming most at risk for a surge of infections.
The CityMD statistics reflect tests done from late April to late June. As of June 26, CityMD had administered about 314,000 antibody tests in the city; citywide, 26 percent of the tests came back positive.
The testing results in Jackson Heights and Corona seemed to “jump off the map,” Dr. Frogel said.