2 5 8 LEPROSY. 



It would also appear that the disease is not readily 

 inoculable in the human subject. In a well-known case 

 described by Arning, a criminal in the Sandwich Islands 

 was inoculated in several parts of the body with a leprosy 

 tissue. Two or three years later, well-marked tubercular 

 leprosy appeared and led to a fatal result. This experiment, 

 however, is open to objections, as the individual before 

 inoculation had been exposed to infection in a natural way, 

 having been frequently in contact with lepers. In other 

 cases inoculation experiments on healthy subjects, and 

 inoculations in other parts of leprous individuals have given 

 negative results. It has been supposed by some that the 

 failure to obtain cultures and to reproduce the disease 

 experimentally may be partly due to the bacilli in the 

 tissues being dead. That many of the leprous bacilli are 

 in a dead condition is quite possible, in view of the long 

 period during which dead tubercle bacilli introduced into 

 the tissues of animals retain their form and staining reaction. 

 There is also the fact that from time to time in leprous 

 subjects there occur attacks of a certain amount of fever, 

 which are followed by a fresh outbreak of nodules, and it 

 would appear that at these times especially multiplication of 

 the bacilli takes place more actively. 



The facts stated with regard to cultivation and inocu- 

 lation experiments go to distinguish the leprosy bacillus all 

 the more strongly from other organisms. Some have 

 supposed that leprosy is a form of tubercle, or tubercle 

 modified in some way, but for this there appears to us 

 to be no evidence. Both from the pathological and 

 from the bacteriological point of view the diseases are 

 distinct. It should also be mentioned that tubercle is a 

 not uncommon complication in leprous subjects, in which 

 case it presents the ordinary characters. 



The mode by which leprosy is transmitted has been the 

 subject of great controversy, and is one on which authorities 

 still hold opposite opinions. Some consider that it is a 

 hereditary disease, or at least that it is transmitted from a 

 parent to the offspring ; others again that it is transmitted by 



