A currently virus-vulnerable, prisoner-packed city jail barge should be turned into a floating hospital for ill Rikers inmates, the corrections union boss told The Post.

As COVID-19 hits New York City, more than 600 prisoners are incarcerated in close quarters on the Vernon C. Bain floating jail. Few New Yorkers know about the boat tied up off the South Bronx that some former inmates call a “slave ship” and is part of Rikers.

Corrections union chief Elias Husamudeen told The Post that he wants the boat turned into a hospital as soon as possible so inmates who test positive at Rikers will be quarantined and its 9,000 correction officers will not be so vulnerable to the virus.

“Let’s take this boat and retrofit it,” Husamudeen said. “Let’s clean it up. We’ve got both cell areas and dormitory areas on the boat. It could be an excellent facility for inmates who truly need to be isolated. Once they’re out of quarantine, they can go back to the other facilities on Rikers.”

Though more than 73 inmates and 58 employees have tested positive for the virus, the Department of Corrections would not provide specific information about the inmates at Bain, a motor-less ship that was towed from Mississippi in 1992. Called “The Boat,” the Lego-like ship has both cells and dormitories but many inmates are in the closely-packed dorms.

“The reality is we have the governor and mayor claiming we don’t have enough hospitals to care for the people who have this virus,” Husamudeen said. “They better stop ignoring this population because it could have a horrible effect on the public. Our corrections officers don’t have the luxury of working from home. They have to go in and out of the jail which means they’re going in and out of a population that could be infected.”

Husamudeen said the ship is not hospital-compliant at present and any modification or re-purposing may require higher staffing levels.

The boat was ordered in 1988 when the city’s jail population was about 22,000 and exploding from the crack epidemic. Only 5,400 inmates remain in the city’s jails, but Bain is still there.

“There’s no way on earth you can practice social distancing on the boat,” says Marvin Mayfield, 56, who served 11 months on the jail barge in 2007 and has since become a jail reform activist with Just Leadership USA.

“It is really tight. If you roll over you can touch the next man in his bed. I call it a slave ship because the housing units look exactly like old pictures of the old slave ships. The beds are bolted to the floor and are lined up in a long, narrow room where beds are head to foot down the center.”

Mayfield said illness was an issue there way before COVID-19. “If someone caught a cold the whole place got sick. Imagine what it’s like now if someone on the boat gets the virus.”

Current protocol at Rikers is to take sick inmates from the boat to the newly-reopened Eric M. Taylor facility at Rikers.

Last week, in an email to Mayor Bill de Blasio and signed by other members of the city council, Councilmember Robert Holden called for immediate testing on Rikers for all corrections officers and employees to stop the spread of the virus.

Council member Rafael Salamanca Jr., who represents the South Bronx, has wanted the boat shut down for years.

“Koch ordered the barge in 1988 and it got here in 1992 because of the exploding [jail] population but [former mayor] David Dinkins said it would be a temporary fix,” Salamanca said. “Twenty eight years later, we have a greatly reduced population but it’s still there.”

Once the pandemic is over, Husamudeen said he’d like to turn the boat into a work release program for inmates.