A NOTE ON THE SPONTANEOUS OCCURRENCE OF 

 BACILLARY DYSENTERY IN MONKEYS. 



By Fred B. Bowman. 

 (From the Biological Laboratory, Bureau of Science, Manila, P. I. 



The epidemiologic factors in the etiology of bacillary dysentery are 

 somewhat obscure. The sudden appearance of acute cases in districts 

 usually free of the disease has been attributed to various causes. Drink- 

 ing water and human carriers are known to be sources of infection and 

 animals have been suggested as possible factors. The following report 

 indicates that the latter may in reality be a source of infection for human 

 beings. 



During March and April, 1910, several cases of severe dysentery 

 developed in monkeys kept in the animal house of the Bureau of Science. 

 Two animals which had been used several months previously in an ex- 

 perimental investigation on trypanosomiasis were found in a condition 

 of extreme prostration similar to that seen in acute human bacillary 

 dysentery and were turned over to me for further study. 



The animals were chloroformed and autopsies were performed. The 

 following excerpts are taken from the protocols. 



Only the rectum and colon are affected, the small bowel shows no abnormal 

 condition. The mucosa of the intestine is markedly injected, showing patches of 

 haemorrhage, and is covered with a sticky coating of bloody mucus. Microscopic 

 examination of the faeces shows a large amount of mucus, some blood, leucocytes, 

 and degenerated epithelium. Ova of CEsophogostomum are present and cysts 

 caused by this parasite are seen in the intestinal wall. 



Some of the mucus portion of the stool was suspended in salt solution 

 and after a short time plates were made from the surface of this suspen- 

 sion, lactose-litmus-agar being used. In twenty-four hours no red col- 

 onies were present, the predominating type being extremely small, clear 

 and blue. Cultures from the heart's blood, liver and spleen were negative. 

 Control plates from the stool of a rnonkey apparently well showed large 

 numbers of red colonies. 



Cultures were made on agar slants from these small, blue colonies and 

 later the following agglutination tests were performed, parallel ones 



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