1887.] 



The Etiology of Scarlet Fever. 



159 



taken by the Medical Department of the Local Government Board as 

 a part of its business of investigating local epidemics. That inquiry- 

 had demonstrated milk from a farm at Hendon as the cause of the 

 scarlatina, and had adduced strong circumstantial evidence that the 

 scarlatina had been distributed, not in the whole, but in certain sec- 

 tions of the Hendon milk, and further that the ability of the sections 

 of milk service to convey the disease had been related to a malady 

 affecting particular cows. This evidence against particular cows at 

 the Hendon farm could not and did not aspire at furnishing direct 

 and definite proof of the connexion of this cow disease with scarlet 

 fever of man, for the inductive methods usually employed by the 

 Medical Department of the Local Government Board when applied 

 to inquiries about epidemic spread of scarlatina can for obvious 

 reasons yield but circumstantial evidence. As on various former 

 occasions, so also on this, the Medical Department sought to put the 

 above conclusions to the test of scientific experiment. This task was 

 delegated to me by the Board. The first part of this work has been 

 published in the recently issued volume of the Reports of the Medical 

 Officer of the Local Government Board for 1885-1886. I have 

 therein shown that the suspected cows from the Hendon farm that 

 had been made the object of special study, showed besides a skin 

 disease — consisting in ulcers on the udder and teats, and in sores and 

 scurfy patches and loss of hair in different parts of the skin — also a 

 general disease of the viscera, notably the lungs, liver, spleen, and 

 kidney, which resembled the disease of these organs in acute cases of 

 human scarlatina. I have further shown that the diseased tissues of 

 the ulcers on the teats and udder produced on inoculation into the 

 skin of calves a similar local disease, which in its incubation and 

 general anatomical characters proved identical with the ulceration of 

 the cow ; and further, that from the ulcers of the cow a species of 

 micrococcus was isolated by cultivation in artificial nutritive media, 

 which micro-organism in its mode of growth on nutritive gelatine, on 

 Agar- Agar mixture, on blood serum, in broth, and in milk, proved 

 very peculiar and different from other species of micrococci hitherto 

 examined. With such cultivation of the micrococcus I have produced 

 by subcutaneous inoculation in calves a disease which in its cutaneous 

 and visceral lesions (lung, liver, spleen, and kidney) bears a very 

 close resemblance both to the disease that was observed in the Hendon 

 cows as well as to human scarlatina. 



The second part of the work, carried out during 1886-1887 for the 

 Medical Department, had for its object to investigate whether or no 

 the disease, human scarlatina, is associated with the identical micro- 

 coccus, and whether this, if obtainable from the human subject, is 

 capable of producing in the bovine species the same disease as was 

 observed in the Hendon cows and in the calves experimented upon 



