While a few cats that were adopted from the shelters during the outbreak had also contracted the virus, it seems to have been contained.

In some ways, the center, with its grids of cells and multiple levels of security to thwart escape attempts, feels like a prison. Inmate No. A1099603 is an orange-and-white tabby named Aries. A sign on his cage says, “Moved from J12 to I45 due to fighting/roughhousing.”

In other ways, it is a giant infirmary. Caretakers note symptoms on the Medical and Behavior Concerns Board (“bloody nose,” “not eating/seems weak”). In makeshift doctors’ offices off the main cage areas, patients are examined and medications dispensed.

The center is staffed by professional animal-crisis workers, who have converged on Queens from all over the country — they are being put up at a hotel nearby — and by local A.S.P.C.A. volunteers. Each morning, about four dozen responders file into the warehouse, on a side street in the Long Island City neighborhood opposite a cold-storage facility and a cement plant. They gather in an open office beneath a chart that lays out the chain of command, get their marching orders, suit up and pass through a plastic-lined portal into the hot zone.

Kristi Heytota, a staffing coordinator for JetBlue in New York who took five days off to help at the center, spent Monday morning scooping out litter boxes and lining the group kennels with fresh paper. Her assignment, which also included feeding the cats, was “tough, but very rewarding,” she said.

Justine Matthews, also on kibble duty, said, “It’s just what we have to do to get these guys well.” She was visiting from the San Diego Humane Society.