The book ‘On Leprosy’ from 1847

In 1847, the book ‘On Leprosy’ was published, financed by the Norwegian government. A year later, a French edition was also published. This was the first modern scientific description of leprosy, and the book formed the foundation of leprosy research for a long time to come, not only in Norway but internationally.

The book was the result of a collaboration between Daniel C. Danielssen and Carl Wilhelm Boeck. Boeck mainly focused on the history and spread of the disease in the rest of Europe, while Danielssen compiled his findings from several years of studying the residents at St. Jørgen’s. Danielsen’s detailed descriptions of the disease’s clinical manifestation and its pathological anatomy were especially valuable. The authors achieved international recognition, while Bergen started being seen as the centre of leprosy research.

For the first time, the book defined leprosy as a specific disease, clearly distinct from other skin conditions. Up until that time, other diseases such as syphilis, psoriasis and certain forms of scabies had often been mistaken for each other as well as for leprosy. Danielsen’s long-term observations at St. Jørgen’s Hospital led to an unambiguous description of what was considered the disease’s two main forms: the tuberculoid form and the lepromatous form.

A large number of pages in ‘On Leprosy’ are dedicated to detailed observations of patients, including descriptions of symptoms, the disease’s progression, treatment trials and anatomical pathological changes detected through autopsies. The volume was accompanied by ‘Atlas Colorié de Spedalskhed’, containing coloured illustrations of the different forms of the disease and various specimens made by the artist Johan Ludvig Losting. ‘On Leprosy’ has been digitised by the National Library of Norway and is available in its online library.