Almost certainly, the density of New York City has played a major role in the spread of the coronavirus. While it circulated among us, millions of New Yorkers touched the same subway turnstiles and sat at the same park benches.
Now density is becoming a problem again as we try to discharge recovering covid-19 patients from the hospital. In other places, a recovering patient might return to a multistory or multibedroom home; in New York City, you’re lucky if your bedroom isn’t also your living room. People worry about going home because their breathing might worsen, but also because they might infect their loved ones.