More than any other disease, leprosy demonstrates the difference between the biological nature of illness and the attributes ascribed to the sick. Indeed, it is fair to say that leprosy and Hansen’s disease (the modern name for true leprosy) stand for different ideas more than different diseases. The word leper is still commonly used to mean one who is hated and shunned by society.
Medieval attitudes towards the leper were based on biblical pas- sages pertaining to ‘‘leprosy,’’ a vague term applied to various chronic, progressive skin afﬂictions, from leprosy and vitiligo to psoriasis and skin cancer. The leper, according to medieval interpretations of the Bible, was ‘‘unclean’’ and, therefore, a dangerous source of physical and moral pollution. Biblical rules governing leprosy demanded that persons and things with suspicious signs of leprosy must be brought to the priests for examination. Leprosy was said to dwell not only in human beings, but also in garments of wool or linen, objects made of skins, and even in houses. Diagnostic signs included a scaly eruption, boil, scab, or bright spot. When the signs were ambiguous, the priest shut the suspect away for as long as two weeks for further observations. When a ﬁnal judgment had been reached, the leper was instructed to dwell in isolation and call out as a warning to those who might approach him, ‘‘unclean, unclean.’’
Islamic teachings also reﬂected fear of leprosy. ‘‘Fly from the
leper,’’ warned the Prophet Muhammad, ‘‘as you would ﬂy from a lion.’’ According to Islamic law and custom, people suffering from leprosy were not allowed to visit the baths. It was said that foods touched by a leper could transmit the disease and that no plants would grow in soil touched by the bare feet of a leper.
A brief survey of modern ﬁndings about this disease may help us
understand the ambiguities and complexities of the medieval literature concerning leprosy. Mycobacterium leprae, the bacillus that causes the disease, was discovered in 1874 by the Norwegian physician Gerhard Hansen (1841–1912). Hansen had observed leprosy bacilli as early as
1871, but it was very difﬁcult to prove that the bacteria found in skin scrapings of patients actually caused the disease. No animal model was available and the putative leprosy bacillus refused to grow in arti- ﬁcial media. It took almost one hundred years for scientists to overcome these obstacles. To honor Gerhard Hansen and avoid the stigma asso- ciated with the term leper, the disease was renamed Hansen’s disease.
What is most surprising about Hansen’s disease is the fact that it is
only slightly contagious. Many people having extended and intimate contact with lepers, such as spouses, nurses, and doctors, do not con- tract the disease, whereas others with little contact become infected. Where leprosy remains endemic, almost all people have been exposed to the infectious agent, but only a small percent actually contract the disease. Those who do seem to have a deﬁciency in their immune system that makes them unusually susceptible M. leprae. Evidence of the lim- ited degree of contagiousness of leprosy today does not, of course, prove that the disease was not more contagious in the past. Nevertheless, lep- rosy could not have been as contagious as medieval writers assumed. Religious and medical authorities argued that leprosy could be spread
A man with leprosy (photographed in Manila in 1899).
by the glance of a leper or an unseen leper standing upwind of healthy people.
Various indeterminate patterns exist between the two polar forms of Hansen’s disease, known as tuberculoid and lepromatous. If infected people mount a partial immune response, the disease will assume the tuberculoid form, which is not infectious or dangerous to others. The early symptoms of tuberculoid leprosy include skin lesions and loss of sensation in the affected areas. Unfortunately, the loss of sensation and the weak immune response may eventually result in damage to tissues. About 80 percent of all cases take this form. Patients with the tuberculoid form mount a partially effective cell-mediated immune response to the infection, although this does not eliminate the bacteria. Individuals with the more severe lepromatous form have essentially no immune response. The bacteria multiply freely and large numbers of bacteria are discharged in the nasal secretions. The lepromatous form is characterized by skin lesions consisting of raised blotches, nodules, and lumps. Eventually, the thickening of the skin of the forehead and
face, exaggeration of natural lines, and loss of facial hair produce the so- called ‘‘lion face.’’ As the disease progresses, ulcerating skin lesions lead to destruction of cartilage and bone. About 30 percent of all victims of Hansen’s disease eventually develop crippling deformities due to damaged joints, paralysis of muscles, and loss of soft tissue and bone, especially the ﬁngers and toes. Loss of sensitivity caused by nerve dam- age results in repeated injuries and infections.
Leprosy seems to have been rare in Europe before the fall of
Rome. Although the disease was creeping into the Mediterranean arena by the sixth century, the Crusades of the eleventh and twelfth centuries created ideal conditions for a major invasion. Indeed, there are estimates that by the end of the twelfth century one out of every two hundred Europeans was infected with leprosy. The high incidence of leprosy among pious persons, especially Crusaders and pilgrims return- ing from the Holy Land, was a potential source of embarrassment to the Church. The Crusades were part of massive movements of human popu- lations that broke down ancient barriers and carried infectious diseases to new populations. However, after reaching its peak in the thirteenth century, leprosy all but disappeared from Europe.
Priests, doctors, and lepers were involved in the examination of alleged medieval lepers. If incriminating signs of leprosy were found— bright spots, depigmented patches, sores, thickened skin, hoarse voice, and ‘‘lion face’’—the accused was found guilty. A funeral service, rather than an execution, followed the verdict. Although the rites of exclusion could be held in a church, performing them in a cemetery with the leper standing in a grave made the symbolic death and burial more dramatic. Having sprinkled earth on the leper’s head, the priest declared him dead to the world, but reborn to God. Although hated by all men, the leper was said to be loved by God and could, therefore, look forward to com- pensation in the next world. The rules governing lepers and marriage reﬂect the ambiguity of the leper’s status. Despite the leper’s symbolic death, leprosy was not necessarily accepted as a cause for the dissolution of marriage. Indeed, the Church decreed that a man with leprosy could require a healthy wife to continue sexual relations.
Feared by all and condemned to live in isolation, lepers were also the conspicuous targets of religious charity. Thousands of leper houses were established by various religious orders throughout Europe. Where lepers were granted the special privilege of begging for alms, other impoverished people apparently pretended to be lepers in order to receive alms or be admitted to leper houses. Miserable as these places might be by modern standards, they were presumably better than the alternatives.
Sometimes lepers were the objects of ‘‘heroic charity,’’ such as that of Queen Mathilda, who expressed her piety by bringing lepers into her own rooms where she fed them and washed their feet. On ﬁnding her so
Leprosy is now known as Hansen’s disease.
occupied, her brother was ﬁlled with revulsion and warned her that King Henry might not enjoy being intimate with a woman who spent her days washing the feet of lepers. Mathilda’s piety was, however, so contagious that she soon had her brother kissing the lepers. In contrast, Philip the Fair of France, thought that lepers should be buried alive or burned to death rather than subjected to merely symbolic rites of isolation and burial.
When in public, lepers were supposed to wear a special costume
and warn others of their approach with a bell, or rattle. Lepers were not allowed to speak to healthy people, but could point with a long stick
to indicate items they wished to purchase. (Presumably, money taken from a leper was not a troublesome source of contagion.) As always, justice or injustice was not equally distributed. Enforcement of the rules of exclusion varied from benign neglect to extreme brutality. The role forced upon the leper was not that of a sick person, but that of a scape- goat for all of medieval society. Perhaps, there were also economic motives at both the state and the family level for the persecution of lepers, who often lost their right to property and inheritance.
Given the ambiguity of the early signs of leprosy, how was it pos- sible to ‘‘discover’’ lepers? Theoretically, lepers were supposed to report their disease to the authorities, but ‘‘closet lepers’’ were probably detected and exposed by suspicious neighbors. Medieval descriptions of all diseases contain highly stylized and speculative material expressed in terms of humoral pathology. The divergence between modern and medieval observations is, however, more striking in the case of leprosy than for other diseases. In the absence of immunological and bacterio- logical tests, even the most skillful modern diagnostician may ﬁnd it dif- ﬁcult to distinguish leprosy from other diseases that produce chronic, progressive skin lesions. Although some changes in clinical patterns may occur over time, it seems likely that medieval authors, whether physicians or priests, often described what they expected to see rather than what they actually saw.
Many medical authorities assumed that leprosy was caused or
transmitted by improper sexual acts, such as intercourse with a men- struating woman, or contact with a healthy woman who had previously had intercourse with a leper. The presumption of a link between leprosy and ‘‘moral deﬁlement,’’ speciﬁcally lechery, persisted into the twentieth century. However, sex and sin were not the only causes of leprosy recog- nized by medieval physicians. The disease could be inherited from a lep- rous ancestor or acquired from the bite of a poisonous worm, rotten meat, unclean wine, infected air, and corrupt milk from a leprous wet nurse. Various diets were commonly recommended to prevent or cure leprosy; almost every food fell under suspicion at one time or other. Indeed, many years of research convinced Sir Jonathan Hutchinson (1828–1913) that eating rotten ﬁsh caused leprosy.
Although the only useful medieval response to leprosy was the iso- lation of the afﬂicted, physicians, quacks, and the Bible offered hope of miraculous cures. According to Matthew, Jesus healed a leper simply by touching him and saying ‘‘be thou clean.’’ In contrast to this instan- taneous cure, Naaman, who was cured by the Prophet Elisha, had to wash himself in the Jordan River seven times. Bartolomeus Anglicus (ﬂ. 1250) admitted that leprosy was hard to cure, except of course by the help of God, but he did suggest a remedy made from the ﬂesh of a black snake cooked in an earthen pot with pepper, salt, vinegar, oil, water, and a special ‘‘bouquet garni.’’ Because this powerful snake soup
would make the patient dizzy and cause his body to swell, theriac was needed to counteract undesirable side effects. Eventually, the patient’s ﬂesh would peel and his hair would fall out, but these problems would subside. An equally promising remedy from a ﬁfteenth-century leech- book combined a bushel of barley and half a bushel of toads in a lead cauldron. The mixture was simmered until the ﬂesh of the toads fell from the bones. The barley brew was dried in the sun and then fed to newly hatched chicks. The chicks were roasted or boiled and fed to the leper.
Driven by fear and hope, desperate lepers might attempt even the most gruesome of cures, be it eating human gall bladders or bathing in blood. Because many transient skin lesions were probably mistaken for Hansen’s disease, appeals to saints, baths, bizarre potions, and strange diets were sometimes followed by miraculous cures of the post hoc ergo propter hoc variety. This well-known logical fallacy, in which sequence is confused with cause, has all too often secured the reputation of useless remedies and healers.
Perhaps, the most surprising aspect of medieval leprosy is the
virtual disappearance of the disease from Europe by the fourteenth cen- tury. Obviously, this change was not the result of any medical break- through. Even the cruel measures taken to isolate lepers were of dubious efﬁcacy in breaking the chain of transmission because the dis- ease has a long latent period during which susceptible individuals may be exposed to infection. Changing patterns of commerce, warfare, and pilgrimages may have broken the chain of contagion by which leprosy reached Europe from areas where the disease remained, and still remains, endemic.
If leprosy all but vanished from Europe with minimal medical or public health advances, could it not be totally eradicated today through deliberate efforts? There are good reasons to consider Hansen’s disease a logical candidate for a global eradication campaign. Unlike bubonic plague, leprosy does not seem to have a natural animal reservoir. There- fore, breaking the chain of person-to-person transmission should eventually eliminate the disease. Leprosy was one of six infectious dis- eases that the World Health Organization selected as targets of a world- wide public health campaign launched in 1975. However, malaria, schistosomiasis, ﬁlariasis, leishmaniasis, trypanosomiasis, and leprosy do not present a major threat to wealthy nations or individuals. Thus, they do not receive the attention that has been awarded to smallpox, poliomyelitis, measles, and other preventable infectious diseases.
Because the early symptoms of Hansen’s disease are similar to many other ailments, its victims may be misdiagnosed and subjected to inappropriate treatments for long periods of time. The drugs most frequently used to treat leprosy are dapsone, rifampicin, and clofazi- mine; often all three drugs are given as a multidrug regimen for six months to two years. Despite the appearance of strains of M. leprae
resistant to each of these drugs, public health authorities argue that if a partial course of therapy were instituted for all lepers, the disease could be eradicated. Even if the afﬂicted individual is not completely cured, drug treatment renders the patient noninfectious and breaks the chain of transmission. Unless resources are allocated for a major assault on leprosy, the worldwide incidence of the disease will inevi- tably increase and multidrug resistant Hansen’s disease will become more difﬁcult to treat.
The World Health Organization estimates that more than one hun- dred years after the discovery of the causative agent for leprosy, about
15 million people are still suffering from the disease. The number could actually be much higher because Hansen’s disease is often misdiagnosed or unreported. Many patients still think of the diagnosis as a curse. About
90 percent of all cases were found in ten countries: India, Indonesia, Brazil, Democratic Republic of the Congo, Guinea, Madagascar, Mozambique, Myanmar, Nepal, and Tanzania, but Hansen’s disease remains a signiﬁcant public health problem in other impoverished areas. For example, in Somalia, during the ﬂoods that affected over sixty vil- lages and over one hundred thousand people in 2000, hundreds of lep- rosy victims were among those forced out of their homes and villages. Some lepers were so debilitated by the disease that they had to be carried in wheelbarrows and carts pulled by donkeys. Most of those suffering from leprosy had been living in perpetual quarantine since the 1980s when they were exiled to two remote villages. Villagers and the authorities in nearby towns quickly expressed concern about the sudden inﬂux of leprosy victims.
The Kalaupapa Peninsula, on the island of Molokai, Hawaii, was once a place of permanent exile for thousands of victims of Hansen’s dis- ease. About eight thousand people have been exiled to Kalaupapa since
1865 when King Kamehameha V signed an act to prevent the spread of
leprosy. Mandatory exile, as well as all admissions to Kalaupapa, ended in 1969. By 2003, only about 40 elderly patients remained. The survivors were too disabled or disﬁgured by the disease to leave a place that once was little more than a prison. The former leper colony became a National Historical Park. Another well-known American leper hospital was founded in Carville, Louisiana, in 1913. Facing strict, life-long isolation, patients described Carville as more like a prison or ‘‘living cemetery’’ than a hospital. By the late twentieth century, almost all cases of Hansen’s disease in the United States were found in immigrants who had contrac- ted the disease in areas where it remains endemic.
Politics and poverty account for much of the difﬁculty in mount-
ing a global campaign against leprosy, but research on Hansen’s disease has also been hindered by the reluctance of M. leprae to multiply and be fruitful in laboratory animals and artiﬁcial media. Research has been facilitated by the discovery that the bacilli will multiply in the
nine-banded armadillo, the footpads of mice, and several nonhuman primates.