Hansen, Gerhard Henrik Armauer

(b. Bergen, Norway, 29 July 1841; d. Florø, Norway, 12 February 1912)

bacteriology.

Hansen was the eighth of fifteen children. His mother was Elisabeth Concordia Schram, who was a member of a family of master joiners long established in Bergen. His father, Claus Hansen, was a wholesale merchant until the severe contraction of credit of 1848–1851 drove him into bankruptcy; he then worked as a cashier in a bank.

In 1859 Hansen began his medical studies at the University of Christiania (now Oslo). It was necessary for him to earn his own living while he was a student. He first taught at a girls’ school and later spent a year as substitute for the prosector of anatomy. He then began his own tuition courses in anatomy. In later years he said that during this period he had known neither physical nor mental fatigue and had found that he did his best work between six and eight in the morning. He passed his degree with honors in 1866 and completed his internship at the National Hospital in, Christiania. He then served as doctor to a community of some 6,000 fishermen at Lofoten, a group of islands off northern Norway.

In 1868 Hansen entered the service of the leprosy hospitals in Bergen. His new chief, Daniel Cornelius Danielssen, had, with C. W. Boeck, published the major work Om Spedalsked (“On Leprosy,” 1847) and had helped to establish Bergen as the European center for leprosy research. Danielssen, like other investigators of the time, regarded the affliction as hereditary (and was to continue to do so throughout his life). Hansen, however, quickly concluded on the basis of epidemiological studies that leprosy was a specific disease which must have a specific cause.

Bacteriology was then in its infancy. In 1870 Hansen received a grant that allowed him to travel to improve his knowledge of histopathology. He went to Bonn and later to Vienna. Returning to Norway, using primitive staining methods and working with biopsy specimens from patients with leprosy, Hansen in 1873 discovered the rod-shaped bodies—Mycobacterium leprae, sometimes called Hansen’s bacillus. By 1879 he was able, through the use of improved staining methods, to show great numbers of the rodshaped bodies typically aggregated in parallel cells. He believed the bacillus to be the causative agent of leprosy and thereby became the first investigator to suggest that a chronic disease might be caused by microorganisms. (The tuberculosis bacillus, for example, was not discovered until 1882.)

Hansen conducted many experiments to prove that his bacillus was indeed the cause of leprosy. He attempted to find a method of cultivating the Mycobacterium leprae on artificial media, without success. (The bacillus has not yet been cultivated in vitro.) He further tried to transmit leprosy to animals and humans; he failed in experiments on rabbits, and experimental reproduction of the disease has not so far been accomplished. In a less well-advised effort, Hansen inoculated the eye of a woman suffering from the neural form of the disease with material drawn from a leprous nodule of a patient suffering from the cutaneous form. There were no clinical consequences of the inoculation, but since Hansen had not asked permission to perform the experiment, he met with legal difficulties as a result of which he was removed from his post as resident physician of the Bergen leprosy hospitals in May 1880.

Hansen’s sentence was less severe than it might seem, however, since he was allowed to retain his position as leprosy medical officer for the entire country of Norway—an appointment conferred on him in 1875 and one that he held until his death. He was thus able to implement changes in the methods of control of Ieprosy in Norway—changes that had been in part made necessary by his own hypotheses concerning the etiology of the disease. The Norwegian Leprosy Act of 1877 and the amended act of 1885 were the fruits of his untiring work. Under these laws health authorities could order lepers to live in precautionary isolation away from their families (subsequent studies have shown leprosy to be a familial affliction); enforcement of the laws led to a quick and steady decline of the disease in Norway. There were 1,752 known cases of leprosy in Norway in 1875; by the beginning of the twentieth century there were 577 (that there are only four known today may well reflect generally improved economic and hygienic conditions). The word “hansenarium” was suggested to replace the still more standard “leprosarium.”

Hansen received many honors for his leprotic studies. He was elected honorary chairman of the first Conférence Internationale de la Lèpre, held in Berlin in 1897, and was president of the second such conference, held in Bergen in 1909. He was honorary chairman of the International Leprosy Committee, corresponding or honorary member of numerous scientific societies, and was decorated several times. In 1900 contributions toward a portrait bust of Hansen were solicited internationally; the bust was unveiled with great ceremony the following year.

While Hansen was chiefly known for his work on leprosy, he also played a role in the dissemination of Darwin’s ideas. He learned of Darwin’s doctrines during his trip to Vienna, early in his career, and he then set about to study Darwin’s books. He sought to emulate Darwin’s methods, which he considered a model of dispassionate observation; in 1886 he published a book on Darwinism in Norwegian. In his apostolic zeal for Darwin’s work, Hansen also gave numerous lectures and published articles in the popular press. These evoked a great sensation, especially from the clergy and religious organizations—who reacted violently against the “blasphemer” in their midst. Hansen was, however, devoid of philosophical speculations and had no aptitude for martyrdom. He did not acknowledge the attacks made against him; he continued to sit at his microscope, smoking his pipe, and do his work.

Hansen married Danielssen’s daughter, Stephanie Marie, on 7 January 1873; she died of pulmonary tuberculosis on 25 October of the same year. On 27 August 1875 he married Johanne Margrethe Tidemand, a widow related to almost the entire Bergen commercial patriciate. Their only child, a son, became a physician specializing in tuberculosis and in 1929 was appointed chief of the tuberculosis hospital in Bergen.

Hansen suffered the first symptoms of heart disease as early as 1900; in following years he had several severe heart attacks that confined him to bed for long periods of time. In the intervals of his illness, however, he continued to travel around the country on official inspection tours. In February 1912 he made such a trip to the fishing areas north of Bergen; in Florø, a little town on the western coast, he was invited to stay in the home of a friend, and it was there that he died. He was given a funeral at state expense; he had been president of the Bergen Museum and the ceremonoy took place from its hall.

BIBLIOGRAPHY

I. Original Works. Hansen’s most important works concerning the bacillus include “Undersøgelser angaaende Spedalskhedens Aarsager” (“Investigations Concerning the Etiology of Leprosy”), in Norsk magazin for laegevidenskaben, 3rd ser., 4 no. 9 (1874), supp. 1–88, case reports I—LIII; “On the Etiology of Leprosy,” in British and Foreign Medical Magazine, 55 (1875), 459–489; “Bacillus leprace,” in Virchow’s Arkiv für pathologische Anatomie und physiologie und für klinische Medizin, 79 (1880), 32–42; “Studien über Bacillus leprae,” Ibid., 90 (1882), 542–548; Leprosy. In Its Clinical and Pathological Aspects (Bristol, 1895), written with C. Looft; and “Lepra,” in Wilhelm Kolle and A. Wassermann, eds., Handbuch der pathogeneb Mikroorganismen, II (Jena, 1903), 178-203.

II. Secondary Literature. On Hansen and his work, see W. H. Feldman, “Gerhard Henrik Armauer Hansen. What Did He See and When?,” in International Journalof Leprosy, 33 (1965), 412–416; B. Helland-Haasen, “G. Armauer Hansen in Memoriam,” in Medical Review (Bergen), 29 (1912), 125–128; O. Lasser, “Gerhard Armauer Hansen,” ibid., 18 (1901), 193–198; C. Looft, “G. Armauer Hansen,” ibid., 29 (1912), 164–166; P. Pallamary, “Translation of Gerhard Armauer Hansen: Spedalskhedens Aarsager (Cause of Leprosy),” in International Journal of Leprosy, 23 (1955), 307-309.

The following works about Hansen were written by T. M. Vogelsang: Armauer Hansen og Spedalskhetens historie i Norge (“Armauer Hansen and the History of Leprosy in Norway”), Universitetet i Bergeny Småskrifter no. 12 (1962); “Hansen’s First Observation and Publication Concerning the Bacillus of Leprosy,” in. International Journal of Leprosy, 32 (1964), 330–331; and Gerhard Henrik Armauer Hansen. l841–1912 (Oslo, 1968), with a bibliography (51 references) and two appendixes, all of which have incomplete listings of Hansen’s work.

T. M. Vogelsang