Why Are So Many People Still Suffering From Leprosy?

Mystery and misconceptions continue to surround the biblical scourge contracted by at least 250,000 people each year.

A leprosy affected woman prays at a Buddhist pagoda in an isolated village south of Hanoi, 2010 (Damir Sagolj/Reuters)

There was a time and a place when, if one wanted to be canonized, going to a leper colony was a surefire way of earning the requisite "angel of mercy" cred. Just last week, "Mother of Outcasts" Marianne Cope was posthumously recognized as a saint by the Roman Catholic Church for her work with people afflicted by leprosy in late 1800s Hawaii. She was the second person working with that same population to receive this rare honor.

Caring for the afflicted made for compelling narrative as well, as nurse and missionary Kate Marsden learned with the 1892 publication of On Sledge and Horseback to the Outcast Siberian Lepers. While the action-packed details of her journey across the taiga occupies the majority of the tome's 300 pages, little compares to the "peculiar thrill" she describes at her first glimpse of the lepers -- as it was then still acceptable to call those suffering from what we now also refer to as Hansen's disease -- who had been banished to small settlements hidden in the depths of the forest:

Some of the people came limping, and some leaning on sticks, to catch the first glimpse of us, their faces and limbs distorted by the dreadful ravages of the disease. One poor creature could only crawl by the help of a stool, and all had the same indescribably hopeless expression of the eyes which indicates the disease. I scrambled off the horse, and went quickly among the little crowd of the lame, the halt, and the blind. Some were standing, some were kneeling, and some crouching on the ground, and all with eager faces turned toward me. They told me afterward that they believed God had sent me...

The lepers, to Marsden's horror, had been entirely forsaken by their communities. They spent much of their time in their book prostrating themselves before her and admiring her refusal to fear them. But if she allowed herself a bit of a heroine complex, Marsden's main objective was to call attention to the lepers' plight. She certainly didn't sugarcoat the dire realities of their exile. "I began to wonder," she writes several chapters later, "why some of these lepers did not, in their desperation, throw themselves in the way of the bears, and so end their miseries."

lepers-inset.jpgThe exiled lepers encountered by Marsden (Google Books)

Descriptions like these seem quaint artifacts of less enlightened times. Surely, there's far less opportunity to be beatified for such self-sacrifice in our era of modern medicine. Multidrug therapy -- while not a full-fledged cure for leprosy -- has caused the number of cases worldwide to drop from 5.4 million to somewhere in the realm of 250,000 since 1985, according to the World Health Organization (WHO). The last two leper colonies in the U.S. -- the one attended by Cope, and another near Baton Rouge -- closed their gates to new residents toward the end of the twentieth century. While infections still occur in this country at a rate of about 200 cases per year, you're most likely to contract the disease through foreign travel or contact with an armadillo.

We also know a lot more about leprosy than we did a century ago, when our knowledge hadn't evolved much from that of biblical times. For example, so far as plagues go, it's actually not very contagious: about 95 percent of people may be naturally immune to the Mycobacterium leprae bacilli that cause the disease. While biblical references to leprosy encompass all sorts of plights to the skin -- both literal and metaphorical -- the disease as modernly defined most potently causes nerve damage.

Still, much about leprosy continues to elude scientific understanding, including the exact means by which it is transmitted. M. leprae can't be cultured in the lab, as it replicates at a snail's pace, taking 12.5 days where most bacteria require mere hours. Partly due to these challenges, the disease remains endemic in other parts of the world, predominately India, Brazil, and Indonesia. The worst cases can result in not just disfigurement, but blindness. Outside of the U.S., it's the leading cause of people losing the use of their hands.

And its biblical and historic associations with sin and shunning die hard (quoth the King James Bible, "And the leper in whom the plague is, his clothes shall be rent, and his head bare, and he shall put a covering upon his upper lip, and shall cry, Unclean, unclean"). Limited awareness of this sort can prevent full-fledged efforts to eradicate the disease from taking hold. "I can take you to places where people live in an isolated leprosy hospital," said Steve Reed, the founder and CEO of the Infectious Disease Research Institute, a nonprofit working, in part, to eliminate leprosy for good. He spoke of people who had been sent to such wholly unnecessary places as children, and of some who had even been born there. He was speaking of the present day.

Margaret Tonga sits between her leprosy-afflicted parents in Mogiri, south Sudan, 2007. Following years of war, they have not been able to receive proper treatment or medicine. (Stringer/Reuters)

Central to the eradication of leprosy may lie not so much in drugs as a switch in the way we think about it. The social stigma it continues to carry keeps it from being perceived, as Reed puts it, as "a disease like any other." WHO considers itself to be in the "final push" of its elimination strategy, and most countries reported meeting its goal of reducing incidences to less than one per 10,000 individuals by the year 2000.

But "the drop-off in the number of new cases just didn't jibe," said Dr. Malcolm Duthie, who heads up IDRI's leprosy work. He cites political motivation in places like India -- where the numbers of reported infections dropped steeply in a short period of time -- to claim the disease is under control. At least one study backs up his claim: In Bangladesh, an active search for leprosy cases turned up five times the number of reported incidences -- in this way, too, people with leprosy have been cast aside. "The easiest way to eliminate a disease is to stop looking for it," said Duthie.

The most recent recommendations released by the WHO are for early diagnosis and early treatment, which can be extremely effective in preventing leprosy's most damaging effects. But drug treatments have a limited scope of efficacy. The disease is extremely slow to manifest -- seven years can pass between infection and the appearance of symptoms -- and it's easy for physicians to misdiagnose. Patients will often be treated, ineffectively, for fungal infections or other skin conditions before finally consulting experts, who are difficult to reach in many parts of the world.

Meanwhile, multidrug therapy requires six months to a year of treatment. During that time, many things can go wrong. While noncompliance isn't a major problem, said Duthie, barriers such as natural disasters may arise that prevent continuous access to the drugs. "It's very difficult to eliminate a disease completely when all you're doing is reacting to cases," said Reed.

He added, "No disease has ever been eliminated without a vaccine." Adding to WHO's efforts, IDRI is in the finalizing stages of two vaccines for those at risk of leprosy and those in the early stages of infection. The first arose from their development of a vaccine for tuberculosis, which, in terms of the bacteria by which it is spread, is a close cousin of leprosy. The second will target leprosy specifically, as is expected to go into phase I testing by late 2013.

IDRI has also developed a blood test -- "similar to a pregnancy test," said Duthie -- that will be ready by the end of the year. The test will be key to getting the vaccine to the right people, and to preventing the damages that, once caused, are permanently debilitating. They are also in the process of putting together an advisory council, and hope to get local governments, doctors, and scientists in affected areas to spearhead the renewed effort at elimination.

In their efforts, IDRI has teamed up with the American Leprosy Mission, a Christian organization that explicitly aims to follow Jesus's example in curing leprosy. In the short term, it's a fine thing to encourage the embrace, instead of exile, of those afflicted ("And, behold, there came a leper and worshipped [Jesus], saying, Lord, if thou wilt, thou canst make me clean"). Scientific advancement, from there, may step in for missionaries and saints and finally take us the rest of the way, relegating leprosy itself to the realm of biblical allegory.