EPIDEMIC DIARRHCEA 305 



borne, obtained an opportunity for fastening on non-living organic 

 material, and of using such organic material both as nidus and as 

 pabulum in undergoiag various phases of its life-history. 



" That in food, inside as well as outside the human body, such 

 micro-organism finds, especially at certain seasons, nidus and 

 pabulum convenient for its development, multiplication, or evolu- 

 tion. 



" That from food, as also from the contained organic matter of 

 particular soils, such micro-organism can manufacture by the 

 chemical changes wrought therein through certain of its life- 

 processes a substance which is a virulent chemical poison; and 

 that this chemical poison is, in the human body, the material 

 cause of epidemic diarrhoea."* 



Bacteriolog"y of Diarrhoea. — The three causal agents which 

 Ballard mentions as playing a large part in the production of this 

 disease are the soil, season, and food — and the causa causans is 

 "some micro-organism not yet detected or isolated." It must be 

 said that we have not got much further than this during the last 

 fifteen years. 



In 1885 Escherich published his classical researches on £. coli 

 communis. He pointed out that the meconium of the newly-born 

 infant is free from bacteria, but by the second day they are present 

 in large numbers, and in the ordinary excreta of healthy infants he 

 found chiefly two organisms, B. lactis cerogenes and B. coli communis. 

 Of these the former was the more abundant in the upper part of 

 the small intestine, and the latter in the lower part and in the 

 colon, so that in the excreta B. coli was abundant, and B. lactis 

 comparatively scarce. Booker, working in 1886 and onwards, found 

 that the constant bacteria of the healthy excreta of the infant 

 (B. coli and B. lactis cerogenes) do not disappear in the excreta of 

 diarrhoea. B. coli, however, does not predominate in the same 

 degree, and B. lactis is present generally in greater numbers than 

 in the healthy excreta. Booker examined the excreta of 31 

 children, and isolated 33 different species of bacteria. Many 

 varieties of bacteria are sometimes found in individual cases of 

 diarrhoea. The greatest number were found in eases of cholera 

 infantum, and a larger number in catarrhal enteritis than in 

 dysenteric enteritis. The actual number of individual bacteria 

 was, he found, as great in the healthy excreta as in the diarrhoeal 

 excreta. Proteus vulgaris was found very generally, and in the 

 most serious cases. No chromogenic bacteria were isolated, and 

 cultures from a large number of green stools failed to develop green 

 colonies. From these facts Booker concluded " that not one specific 



* Sii/pplement to the Report of the Medical Officer of the Local Oovemment Board, 



1887. 



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