LEPROSY 53 



Even in Louisiana where there is a state colony, isolation is not effec- 

 tively carried out. 



The Bacillus. The bacillus discovered by Hansen of Bergen is 

 believed to be the specific cause of leprosy, although all the condi- 

 tions necessary to establish this fully have not been complied with. 

 This organism is a long (1.5-6 microns), slender (0.2-0.5 micron) 

 rod, which is acid-fast and belongs to the same group as the tubercle 

 bacillus! It takes fuchsin and similar stains more readily than the 

 tubercle bacillus and loses the stain more easily when washed with 

 dilute mineral acid. However, these differences are so slight and vary 

 so much with different strains of both organisms, that they do not 

 give a means of positive differentiation. The leprosy bacillus is oftener 

 found in bundles and these are larger than those of the tubercle 

 bacillus. This is not always distinctive, however. Much effort has 

 been made to find some certain method by which the microscopic dis- 

 tinction between the two organisms may be determined. An expert 

 in this work may distinguish these in many instances, but ordinarily 

 it is not easy. The bacillus of leprosy may be mistaken not only for 

 the tubercle bacillus, but it may be confounded with nonpathogenic 

 acid-fast organisms, such as the smegma bacillus. The leprosy organ- 

 ism seems more truly parasitic than the tubercle bacillus and so far 

 it has not been grown satisfactorily on artificial media, unless the 

 method of Clegg be an exception. This American investigator uses 

 a bouillon to which amebas'from dysenteric stools have been added. 

 This preparation is inoculated with leprosy tissue and some observers 

 have succeeded in obtaining a growth which at the last report had 

 been carried to the tenth generation. Attempts to inoculate the lower 

 animals with leprosy material have not been convincing. A number 

 of men have submitted themselves to this experiment and still the 

 result is left in doubt. In several cases this test has been negative. 

 In others it has been positive, but in all of the latter the tested indi- 

 viduals have been associated more or less intimately with lepers. The 

 Hawaiian convict, who had his choice between suffering the death 

 penalty and inoculation, developed local lesions but these soon dis- 

 appeared. For nearly two years he remained apparently well and 

 then developed the disease, of which he died after four years. This 



