In the most serious measure taken since New York City began its reopening, health officials will begin regular inspections of all non-public schools in portions of Brooklyn and Queens that are experiencing alarming upticks in coronavirus cases. Should cases continue to rise through Monday evening, the city may impose greater restrictions, including the closures of private schools and non-essential businesses.

The neighborhoods that have been identified with high positivity rates are Gravesend, Midwood, Borough Park, Bensonhurst, Sheepshead Bay, and Williamsburg in Brooklyn and Far Rockaway and Kew Gardens in Queens. With the exception of Williamsburg, all of those areas have a positivity rate of more than 3%, higher than the citywide rate of 1% and a warning signal for health officials. Gravesend's positivity rate is 6%.

City health officials have expressed particular concern about the spread of the virus among the city's Orthodox community and compliance among yeshivas has been an issue in some areas since the crisis began. Last Monday, the city ordered a yeshiva in Far Rockaway to close after more than a dozen cases were discovered. But the school continued to hold classes on Tuesday before switching to remote learning after health officials arrived.

On Wednesday, several Orthodox residents in Borough Park told Gothamist that there were unaware of an uptick and that they had seen little sign of an increased public awareness campaign or enforcement. Unmasked congregants were seen crowding into one synagogue.

The Department of Health on Wednesday said that mask wearing in the cluster spots has been "overwhelmingly low compared to other areas of the city." It added that the city's Office of Special Enforcement found customers failing to wear masks in stores.

While Mayor Bill de Blasio has refrained from singling out a single group, some in the Orthodox community have been urging the city to be clearer with its messaging.

Health officials have said they want cases to decline within the next three days. In an email to reporters on Wednesday, the Department of Health wrote, "For the first time in the city's recovery period, there could be the immediate scaling back of activities in these ZIP codes if progress is not made by Monday evening."

Yom Kippur, the Jewish holiday during which members self-reflect and take part in fasting and prayers, is set to begin Sunday night.

The city's list of threatened crackdown actions includes banning gatherings of more than 10 people; issuing fines for those who refuse to wear a mask after being offered one; ordering private schools and child care centers to close; and shutting down all non-essential businesses.

On Wednesday, Dr. Mitchell Katz, the head of the public hospital system who grew up and attended a synagogue in Ocean Parkway, pleaded with the community to take the city's warnings seriously. He said his father-in-law had died from covid two nights ago in Israel, which recently issued a second lockdown order amid worsening infection rates.

"In the absence of us doing the right thing we will need to be in a lockdown situation," he said. "We don't want that. We want people to wear masks, we want them to stay apart, to not have any large gatherings."

The Department of Health first issued an alert about the neighborhoods on Tuesday night. Members from several city agencies along with NYPD have been deployed to step up enforcement. Health officials have made robocalls as well as placed ads in local newspapers to promote awareness of public health precautions. On Thursday, five sound trucks and multiple ambulances drove through the neighborhoods broadcasting messages in both Yiddish and English. The effort will continue through Friday.