THERAPEUTIC IMMUNIZATION IN MAN 499 



in 1837, stated by Abraham Colles, 115 of Dublin, is the well-known 

 generalization based on the observation that mothers who have borne 

 syphilitic infants were not infected by their children while suckling 

 them, although such children might often infect wet nurses. Pro- 

 f eta's 116 observation was the converse of this, namely, that children 

 born of mothers who suffered from active syphilis during the period 

 of conception did not acquire the disease from their mothers. 



Both of these phenomena appear too well founded in clinical 

 observation to be questioned, at least as frequent occurrences. More- 

 over, considering the intimate contact between mother and infant 

 during the first months after birth, they acquire unusual importance. 

 However, as we shall see, they have been deprived of much of their 

 bearing as proofs of true acquired or inherited immunity by serologi- 

 cal investigations such as those of Bauer, 117 Knopf elmacher, 118 and 

 others, which have shown that mothers of syphilitic children usually 

 give positive Wassermann reactions, a fact which makes it seem 

 likely that such women are suffering from syphilis in a latent form 

 and are not immune in the ordinary sense. This indeed was the 

 interpretation given to the "laws" of Colles and Profeta by 

 Fournier 119 and by Matzenauer 12 at a time prior to that at which 

 serological data were available. It is still unclear why such mothers 

 should so frequently exhibit the disease in a latent form. However, 

 this is a matter for the intelligent discussion of which we are not 

 at the present time in the possession of sufficient information. 



In the years just preceding the period of experimental investi- 

 gation of syphilis upon animals much purely clinical research was 

 carried out on the problem of reinoculation and what is commonly 

 known as "superinfection" of syphilitic human beings. Much of this 

 work is unavailable as scientific evidence owing to the difficulties of 

 distinguishing, at that time, between the true chancre and the 

 chancroid, but a considerable number of the observations then made 

 have been of much value in pointing out directions of later research 

 upon animals. The work has been so thoroughly analyzed both by 

 Neisser and by Levaditi that it would be needless repetition to do so 

 again. The records include both accidentally occurring superinfec- 

 tions, and purposeful experimental reinoculations. Without, there- 

 fore, going into details concerning the individual cases we may sum- 

 marize the conclusions justified from a study of these observations. 



115 Colles. Cited from Osier & Churchman, "Syphilis," Osier's System of 

 Medicine. 



116 Profeta. Cited from Osier and Churchmann, "Syphilis." Trattato 

 Practico delle Malattie Veneree, Palermo, 1888. 



117 Bauer. Wien. klin. Wchnschr., 1908, No. 28. 



118 Knopf elmacher and Lehndorff. Med. klin., 1909, No. 40; Wien. med, 

 Wchnschr., 1909, No. 38. 



119 Fournier. L'Heredite Syphilitique, Paris, 1890. 



120 Matzenauer. Vererbung d. Syphilis-Wien., 1905, cited from Bruck. 



