“However, we are seeing sustained increases, and that is worrying,” he said. “And the other thing that’s a big deal is that if the new tension gets a foothold here, it can really spread very quickly.”
Epidemiologists are careful to call for immediate new closures. Instead, they are now asking for targeted measures to try to lower infection rates, such as testing more in the postcodes that are most affected and among the most vulnerable.
Conversely, the parts of the city with the lowest number of viruses – affluent zip codes in Manhattan and Brooklyn – tend to have the highest tests, city data show. That must change, said dr. Frieden said, with more tests in areas hit hard.
Patrick Gallahue, a spokesman for the city’s health department, said the city was already focusing on its test resources in hard-hit areas. Additional restrictions on businesses or events, he said, would be imposed by the state.
But changing the course in New York before a vaccine takes effect is likely to take more drastic measures, such as a closure, several experts said.
City officials need state permission before instituting any city-wide closures except for schools. Mr. Cuomo suggested that schools should close only if the infection rate in school buildings is higher than that of the community. As of the middle of the week, the positive test rate in the city was much less, by 0.49 percent.
Dr. Nash said other red lines and parameters need to be set to guide shutdown decisions, such as one related to deaths: How many deaths per day will we accept before we lock up? He also called for more attention to be paid to local conditions, such as the number of viruses in neighborhoods with overwhelming intensive care units, and the speed of transmission of the virus, a measure known as R0, which is not regularly published by the state. does not become. Government officials say they are tracking the numbers internally.