LEPROSY 399 



produced by the bacillus of Hansen. Bordoni-Uffreduzzi maintains 

 that the parasitic existence of the B. leprce may alternate with a 

 saprophytic stage. This may be of importance in the spread of the 

 disease. There is evidence in support of the non-communicability of 

 the disease by heredity or contagion. Segregation does not appear 

 always to result in a decline of the disease, as we should expect if 

 it were purely contagious. Ehlers, of Copenhagen, has, however, 

 as recently as 1897 reaffirmed his belief in the contagiousness of 

 leprosy ; Virchow, on the other hand, declared that it was not highly 

 contagious. There is evidence to show that persons far advanced 

 in the disease may live in a healthy community, and yet not infect 

 their immediate neighbours. Indeed, the transmission of the disease 

 is still an unsolved problem. Mr Hutchinson maintains that diet, 

 particularly uncooked or putrid fish, is a likely channel. Deficiency 

 of salt, telluric and climatic conditions, racial tendencies, social 

 status, poverty, insanitation, drinking-water, even vaccination, have 

 all secured support from various seekers after the true channel by 

 which the bacillus gains entrance to the human body. The real 

 mode of transmission is, however, still unknown. The decline and 

 final extinction of leprosy in the British Islands was, as we have 

 stated, probably due in part to the natural tendency of the disease 

 to die out, and in part to a general and extensive social improvement 

 in the -life of the people, to a complete change in the poor and 

 insufficient diet, and to general sanitation. 



At the Leprosy Congress held in Berlin in 1897, Hansen again 

 emphasised his belief that segregation was the cause of the decline 

 of leprosy wherever it had occurred. But there appears to be 

 evidence to show that leprosy has declined where there has been no 

 segregation whatever, and therefore, however favourable to decline 

 such isolation may be, it would seem not to be an actvially necessary 

 condition. At the same Congress Besnier declared in favour of the 

 infective virus being widely propagated by means of the nasal 

 secretion. Sticker states that the nasal secretion contains myriads 

 of lepra bacilli, especially in the acute stages of the disease, and 

 Besnier and Sticker have pointed out how frequently and severely 

 the septum nasi and skin over the nose is affected in leprosy. Several 

 leprologists in India have recorded similar observations. These facts 

 appear to support Besnier's contention, that the disease is spread by 

 nasal secretion. 



We may add here the conclusions arrived at by the English 

 Leprosy Commission * in India : — 



" 1. Leprosy is a disease sui generis ; it is not a form of syphilis 



* Dated 1890-91. The Commissioners were the late Beaven Eake, M.D., G. A. 

 Buckmaster, M.D., the late Prof. Kanthack, of Cambridge, the late Surgeon-Major 

 Arthur Barclay, and Surgeon-Major S. J. Thomson. 



