This chapter deals with a disabling disease of paramount importance in the Middle Ages – leprosy. I have chosen to include leprosy in a book dealing with physical disabilities for a number of reasons. First, leprosy is indeed disabling, both in the medical sense and from a social standpoint since a diagnosis of leprosy could result in social isolation and stigmatization. Secondly, the disease may manifest symptoms, especially skin lesions, that result from the constricted flow of blood to the body's extremities, that make the leper as visible, if not more so, than other disabled persons in a community. Also, the symptoms of leprosy can develop slowly over time, thus subjecting the afflicted to long years of the experience of disability.

Medical Knowledge

The cause of leprosy was not discovered until 1873, when Gerhard Armauer Hansen identified the organism responsible for the disease, the mycobacterium leprae. The organism multiplies and affects peripheral nerves, the skin, and finally the bones; the rate of progression of the disease depends on the individual's immune system. Leprosy is not, in fact, very contagious and is usually spread by contact with nasal fluid from an infected individual, but even in cases where such contact occurs, many people have natural resistance to the bacteria. If contracted, the disease can range from the mild tuberculoid type known as paucibacillary leprosy to the more serious multibacillary form that results in gross physical disfigurement. The milder form can manifest itself as pale areas of desensitized skin but it can worsen and later result in crippling from atrophy, secondary infections, and, finally, loss of the extremities. Luke Demaitre addresses the very valid question about whether the disease identified by Hansen, and often called Hansen's disease, was identical to Pre-Modern leprosy. This is basically impossible to determine unless one is a paleopathologist but, due to the similarities in symptoms and for the purposes of this study it is assumed that the diseases were at least very similar in their physical manifestation. Leprosy spread gradually through Europe, especially after the tenth century and seems to have abated somewhat by the fifteenth.