1891.] MICROSCOPICAL JOURNAL. 43 



Protective Inoculations. 



By B. MEADE BOLTON, M. D., 



BROOKLYN, N, Y 



[From Brooklyn Medical yournal, June-September, 1890. J 

 {^Continued frotn November, jSgo, page 2jj.'\ 



It is apparent, therefore, that the question of the practicability of pro- 

 tective inocuhition for animals is not yet settled. Protective inoculation 

 in human beings has been less studied than inoculations in animals from 

 the nature of the case. Among the first experiments under the former 

 head come Fehleisen's inoculations with cultures of the streptococcus 

 of erysipelas for the production of erysipelas, with a view to arresting 

 the growth and causing the disappearance of malignant growths. These 

 inoculations difier in principle from all the inoculations mentioned above, 

 in that their object is to produce, secondarily, an entirely difierent dis- 

 ease, which, in some cases, is found to supplant the mor6 severe primary 

 afiection. Fehleisen was justified in these experiments by the clinical 

 observation that malignant growths sometimes disappear if the patient 

 acquires an attack of erysipelas. Fehleisen's results were encouraging. 

 The artificial production of erysipelas in the way above described has 

 been repeatedly tried of late years, and often with the best therapeutic 

 efiect. Persons who have recently had an attack of erysipelas are not 

 susceptible to the disease by inoculation. This method of preventing 

 and curing a disease by inoculating cultures of micro-organisms of other 

 diseases has been tried to a considerable extent upon animals ; but it has 

 been restricted as yet to laboratory experiments, and has not been tried 

 practically upon the large scale for the prevention or cure of natural out- 

 breaks. The starting point for these experiments was Emmerich's ob- 

 servation that animals inoculated with virulent cultures of anthrax bacilli, 

 and either simultaneously, immediately before, or directly afterward, in 

 the same spot with cultures of erysipelas streptococci, did not die. Paw- 

 lowsky, in consequence of this observation, made a large number of 

 experiments upon animals. He inoculated with cultures of anthrax 

 various other organisms together. He found that local malignant 

 pustule in animals could be prevented by inoculating into the seat of 

 disease several different kinds of micro-organisms ; but he got the most 

 uniform results by injecting Friedlander's so-called pneumonia bacilli 

 either simultaneously with or subsequent to the inoculation with anthrax. 

 Inoculations with cultures of pus staphylococci and anthrax give similar 

 results. Inoculations of cultures of bacillus prodigiosus, after inocula- 

 tions with cultures of the anthrax bacillus, also prevented the latter from 

 producing the disease, though not so uniformly. Where cultures of 

 anthrax bacilli were injected into a vein, the Friedlander's bacillus was 

 the only one which had any effect in arresting the.appearance of anthrax, 

 and this was successful only in rare cases. 



The protective inoculations for hydrophobia have attracted more in- 

 terest by far than any other efforts in this direction. For the benefit of 

 those who are not tamiliar with the fundamental principle and gradual 

 development of these inoculations, the following resume of Baumgar- 

 ten ( Jahresbericht ii. d. Fortschr. i. d. Lehre v. d. path. Mikro., etc., 

 Brauschweig, 1S87) may be of use: "After Brown-Sequard and 

 Duboue had already made it appear very probable that the main seat of 

 disease in hydrophobia is in the central nervous system, Pasteur es- 



