i8o DISEASES DUE TO BACTERIA 



The Spaniards perhaps took the disease to America. 



In the i6th century the imported West African slaves carried it to 

 the West Indies, the Chinese to the Sandwich Islands, Colombia, Ntnv 

 Zealand, &c. 



It was carried to South Africa by the Dutch from Java in 1756, and 

 by the East Indian troops in the 19th century, 



Hansen discovered a bacillus in 187 1, and associated it with the 

 causation of the lepra lesion in 1877. 



The method of infection is unknown. 



DISTRIBUTION. 



Present in Ireland in 432 a.d., and in England in 950 a.d. 



The last British leper died in the Shetland Isles in 1798. 



Present in Iceland, Spain, Italy, Balkans, Crete, Cyprus, Norway, 

 Sweden and Greece. Common throughout Asia, Ceylon, India, 

 Australia (Queensland and New South Wales). The Sandwich 

 Islands in 1891 had one in thirty infected, 1,500 in all. It is present 

 in the United States, Mexico, Central America, Colombia, West 

 Indies, Venezuela, Guiana, Brazil, Africa and Egypt, which was 

 probably its original home. 



In India, in 1891, there was one leper in every 2,000 people, 105,000 

 in all. 



In New Caledonia there w^ere no lepers in 1865. A Chinese known 

 leper w^ent there, and later in 1888 there were 4,000 lepers. 



In the 13th century there were 19,000 leper houses in Christendom, 

 according to the Benedictine monk, Mathew Paris. 



In France there were 2,000 and in England 95, besides smaller pest 

 houses in Ireland and Scotland (Sir James Simpson). 



1890, there were 1,100 lepers in Norway. 



1906, there were only 500 there. 



1915, there were 40 lepers in the United Kingdom (Dr. George 

 Pernet). 



THE BACILLUS. 



Hansen's Bacillus laprse resembles T.B. in size, shape, and stain- 

 ing reaction. Stain as for T.B., but use a weaker solution of H2SO4, 

 5 per cent., in decolorizing. For films and thin sections use the 

 H2SO4 solution for fifteen seconds. 



It has been found in nasal secretion, tears, saliva, sputum, milk, 

 semen, urethral and vaginal secretions, faeces, skin scales, extra- and 

 intra-cellular in liver, spleen, glands, and breaking-down tubercles. 



It has not been found in earth, dust, air, water or food. 



It is doubtful if it has ever been cultivated. 



It is acid-fast, but stains more readily than T.B. with cold, weak 



