Armauer Hansen of Bergen, the leading authority of his time on leprosy, first identified the leprosy bacillus in Norway where the disease was endemic. Leprosy had been thought to be a hereditary affliction. Hansen concluded from epidemiological studies that it was infectious and that the rod shaped bacilli he observed (in 1873) were the cause of leprosy. His claim was not acknowledged for many years. Hansen never managed to fulfil the postulates of Robert Koch and transmit the disease to animals or men using the bacilli. This difficulty was also met with by later workers. Hansen was forced to resign from the Bergen Leprosy Hospital in 1880 after injudiciously injecting live leprosy bacilli into a patient without first obtaining her permission. Nevertheless, he carried on with his own research. By implementing a policy of limited isolation he succeeded in reducing the Norwegian incidence of leprosy from 2833 cases in 1850 to 140 in 1923. He was honoured philatelicaily by France in 1973 on the centenary of the identification of the leprosy bacillus (Stanley Gibbons 2013, Scott 1379).

• Download figure
• Open in new tab
• Download powerpoint