306 BACTERIA AND DISEASE 



organism, but many different varieties of bacteria, are concerned in 

 the etiology of the summer diarrhoeas of children. 



From 1889-1895 Booker continued his studies, isolating bacteria 

 from the rectum in 92 infants affected with epidemic diarrhoea, and 

 also from the organs of 33 infants who died from this disease. He 

 found the conditions for the development of bacteria in the 

 intestine of infants affected with summer diarrhoea different from 

 those in the healthy intestine of milk-fed infants, in that they 

 favoured more varied bacterial vegetation, a rich growth of the 

 inconstant species of intestinal bacteria, and a more uniform dis- 

 tribution through the intestine of the two constant varieties of 

 healthy excreta bacteria {B. coli communis and B. lactis cerogenes). 

 The first step in the pathological process, Booker believes to be a 

 direct injury to the epithelium from abnormal or excessive fermenta- 

 tion and from toxic products of bacteria ; and secondly, a general 

 intoxication may be brought about indirectly through the production 

 of soluble poisons. He holds that, bacteriologically and anatomically, 

 three principal forms of summer diarrhoea of infants may be 

 provisionally distinguished: (i.) dyspeptic or non-inflammatory 

 diarrhoea ; (ii.) streptococcal gastro-enteritis ; and (iii.) bacillary 

 gastro-enteritis.* As a result of his extended researches, Booker 

 came to a general conclusion which he expressed as follows : " No 

 single micro-organism is found to be the specific excitor of the 

 summer diarrhoea of infants, but the affection is generally to be 

 attributed to the activity of a number of varieties of bacteria, some 

 of which belong to well-known species, and are of ordinary occurrence 

 and wide distribution, the most important being the streptococcus 

 (enteritidis) and Proteus vulgaris." The streptococcus termed S. 

 enteritidis varies in morphology, and seems to be associated with 

 two classes of cases, one of' which simulates cholera, the other 

 typical enteric fever. "Micrococci are present in all cases, some- 

 times in enormous numbers." ] It may be added that Cumston, 

 Hoist, Escherich, and Hirsch have also laid emphasis upon the 

 causal relationship of certain streptococci and diarrhoea. 



Klein was one of the first workers to isolate an anaerobic 

 organism from cases of epidemic diarrhoea. This organism, which 

 he named B. enteritidis sporogenes, was found in three successive 

 outbreaks of diarrhoea occurring among patients in St Bartholomew's 

 Hospital. In the first two outbreaks the milk was evidently the 

 channel of infection, in the third it was some rice pudding. The 



* Johns Hopkins Hospital Reports, 1896, vol. vi., p. 253. See also a paper " On 

 the Growth of Bacteria in the Intestine," by Lorrain Smith and Tennant Brit. 

 Med. Jour., 1902, vol. ii., p. 1941. Also Jeffries, Trans. American Pediatrics 

 Society, vol. i., 1889; Baginsky, Archiv. f. Kinderheilkunde, xii., Nos. 1 and 2; 

 Berliner klin. Woch., 1889 ; and Flexner and Holt's Rockefeller Inst. Rep., 1904. 



f Johns Hopkins Hospital Reports, 1896, vol. vi., p. 251. 



