For millennia, a diagnosis of leprosy meant a life sentence of social isolation. People afflicted with the condition now known as Hansen’s disease—a bacterial infection that ravages the skin and nerves and can cause painful deformities—were typically ripped from their families, showered with prejudice and cruelly exiled into life-long quarantine.

In the United States, patients were confined to a handful of remote settlements, where over time, a crude existence evolved into one with small touchstones of normalcy. But patients were consistently deprived of fundamental civil liberties: to work, to move freely and see loved ones, to vote, to raise families of their own. Some who bore children had their babies forcibly removed.

By the 1940s, after a cure emerged for the condition—and science made clear that most of the population had a natural immunity to it—other countries began to abolish compulsory isolation policies. But in the U.S., even as leprosy patients' health and conditions improved, old stigmas, fear of contagion and outdated laws kept many confined for decades longer.

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A tiny number of Hansen’s disease patients still remain at Kalaupapa, a leprosarium established in 1866 on a remote, but breathtakingly beautiful spit of land on the Hawaiian island of Molokai. Thousands lived and died there in the intervening years, including a later-canonized saint. But by 2008, the settlement's population had dwindled to 24—and by 2015, only six remained full time, despite having long been cured. Now in their 80s and 90s, many residents first arrived on the island as children. They knew no other life.

“When they came here, the law guaranteed them a home for life, and that can't be taken away,” doctor Sylvia Haven, a doctor at the island’s hospital, told The New York Times in 1971. For some, that “home for life” translated more closely to a prison, however picturesque. “You were brought here to die,” said Sister Alicia Damien Lau, who first came to the Molokai in 1965, in a 2016 interview. “You were not able to leave the island.”

While patients’ families could visit, they were housed in separate quarters, and allowed to communicate only through a chicken wire screen. “They catch you like a crook and you don’t have any rights at all,” Olivia Robello Breitha, a longtime patient, wrote in her 1988 autobiography. “They didn’t care about ruining a life... I was just a number.”

Kalaupapa was one of a small handful of leper colonies in the United States. Among them were tiny Penikese Island in Buzzard’s Bay, off the coast of Massachusetts, and the Carville National Leprosarium, in Louisiana. With almost 8,000 patients over about 150 years, Kalaupapa was by the far the largest.

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Named for Gerhard Armauer Hansen, the Norwegian doctor who discovered the bacteria in 1873, Hansen’s disease continues to infect people all over the world. In 2015, around 175 cases were reported in the US. In the worst cases, the bacterial infection damages the skin and nerves, leaving patients numb and susceptible to injury. Affected body parts sometimes become gangrenous and must be amputated, or are reabsorbed into the body.

The "separating sickness” was long thought to have no cure. Despite historic connotations of sexual impropriety, leprosy is usually spread via saliva or, more unusually, through contact with an armadillo. (There’s good evidence that what we call leprosy today may in fact not be the same condition described in ancient texts.) Some 95 percent of people are naturally immune, while those who contract the infection can be easily treated with a cocktail of inexpensive antibiotics. To this day, however, the intense stigma surrounding leprosy continues to prevent patients from seeking the straightforward care that can stop terrible disfigurement in its tracks.

In the decades before treatment was found, the U.S. government sought to isolate the bacteria through a policy of segregating patients. In 1917, about 50 years after the Kingdom of Hawaii first began sending patients to Kalaupapa, the government federalized the Louisiana Leper Home at Carville, in Louisiana, which had been run by Daughters of Charity nuns. The first patients from outside the state arrived in 1921.

Life in these communities could be intensely lonely, with few rights and no opportunity to leave. In Kalaupapa in particular, patients led a bittersweet existence. On the one hand, they were forced to live in isolation, far from their lives and families, below treacherous, insurmountable sea cliffs. Most died within a decade of arrival. But on the edge of the Pacific, against a backdrop of incredible natural beauty, many eked out a happy life, between softball games, church worship and even dances. Nearly 1,000 couples on the island married between 1900 and 1930, with some going on to have children. Tragically, babies were taken from their mothers and raised elsewhere.

At Carville, conditions during the earliest decades were rugged. When the facility was first established in swampy, malaria-prone territory outside Baton Rouge, the afflicted were initially housed in former slave cabins, where they shivered and sweltered through the seasons. Their lives were initially bound by fences—one that divided the men's side of the campus from the women's side (since interactions between the sexes were strictly forbidden) and a tall iron perimeter fence to thwart the many escape attempts. There was even an on-site jail to punish runaways, who were sometimes brought back in leg irons. And patients had to sacrifice their very identities: Upon arrival, they were immediately encouraged to take a new name to protect their families back home from the disease's powerful stigma.

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Eventually, a hospital was built on the Carville site, and emphasis shifted from a culture resembling incarceration to one focused more on treatment and research. And after the 1940s brought a cure, some restrictions began to ease within confinement. In 1946, patients were allowed to vote again. Over time, a bustling community developed as residents married, built homes, planted gardens, published a magazine, developed small craft businesses and even enjoyed a pint-sized Mardi Gras festival.

Still, official government health policy regarding the confinement of Hansen’s disease patients changed at a glacial pace, with individual facilities easing their restrictions for decades before federal laws finally caught up with the science.

Patients have been free to leave Kalaupapa since 1969; 30 years later, Carville’s remaining patients were offered a choice between moving on, with an annual stipend of $46,000; remaining at the facility; or being transferred to a home for elders. In both cases, many chose to stay, having grown accustomed to what The New York Times described in 2008 as “the counterintuitive twinning of loneliness and community.” Here, in isolated outposts they might never have chosen, fellow patients, health workers and pastoral staff became family. And for these last remaining few, these distant locations became something approaching home.