PROTOZOAN PARASITES OF MONKEYS AND MAN 



2.31 



amoebae have also been used for the culti- 

 vation of amoebae from monkeys . Dobell 

 (19x6, 19x7) has carried on cultures of the 

 histolytka-like amoebae of monkeys for 

 many months and finds no differences 

 between their reactions in culture and 

 those of E. histolytica from man. Kessel 

 (19x6a) and Vogel (19x7) report similar 

 results. 



The data available lead to the following 

 conclusions regarding Endamoeba histolytica 

 from man and the histolytica-like amoebae 

 from monkeys: (1) The histolytica-like 

 amoebae of monkeys, which have been 

 given at least five distinct specific names, 

 all belong, probably, to one species, 

 Endamoeba nuttalli Castellani 1908, if 

 they are not identical with E. histolytica. 

 (x) There are no satisfactory morpho- 

 logical characteristics by means of which 

 the histolytica type of amoebae of mon- 

 keys and man can be distinguished. (3) 

 Histolytica-like amoebae have been 

 reported principally from captive monkeys 

 that may have become infected by the 

 ingestion of food or drink contaminated 

 with cysts from man. (4) Amoebic 

 dysentery and amoebic liver abscess in 

 monkeys resemble these diseases in man. 

 (5) Most monkeys and men infected with 

 histolytica amoebae are carriers. (6) 

 Monkeys have been successfully infected 

 with E. histolytica from man. (7) Human 

 beings seem to have become infected by 

 association with monkeys. (8) Kittens 

 may be infected by amoebae from both 

 monkeys and man. (9) Histolytica 

 amoebae from monkeys and man exhibit 

 similar reactions under cultivation in 

 artificial media. (10) Either the histoly- 

 tica-like amoebae of monkeys belong to 

 the species Endamoeba histolytica or else 

 we have not yet discovered differences 

 sufficient to distinguish one from the 

 other. 



The situation as regards Endamoeba coli 



of man and the coli-like amoebae of 

 monkeys is similar to that of E. histolytica, 

 but not so much evidence is available. 

 Brumpt, in 1909, reported amoebae with 

 eight-nucleated cysts from three speci- 

 mens of Macacus sinicus. Three years 

 later, Prowazek (191X) gave the name 

 Endamoeba pithed (jigs, xa, xb) to an 

 amoeba with an eight-nucleated cyst that 

 he obtained from a young orang. New 

 specific names have since been given to 

 three other coli-like amoebae found in 

 other species of monkeys (Mathis, 191 3; 

 Macfie, 1915; Mello, 19x3). There is 

 little evidence that these are actually 

 separate species, and they probably all 

 belong to the species E. pitheci if they are 

 not identical with E. coli from man. 

 Kessel (19x4, 19x7) has succeeded in 

 infecting monkeys with E. coli from man 

 and both Dobell (19x6) and Kessel (19x7) 

 have cultivated the coli-like monkey 

 amoeba in vitro. At the Pasteur Institute 

 in Paris, Deschiens (19x7) found coli- 

 like amoebae in 5 of 7 chimpanzees and 

 successfully infected a young chimpanzee 

 and a Macacus monkey with them; his 

 attempt to infect a cat proved negative as 

 did a similar attempt by Brumpt (1909b). 

 Apparently, therefore, there is no good 

 evidence that the coli-like amoebae of 

 monkeys differ in species from E. coli in 

 man. 



Amoebae of the genus Endolimax (figs. 

 4a, 4b) have been reported from monkeys 

 by only two investigators. Brug, in 

 19x3, found in an old laboratory monkey 

 (Macacus cynomolgus*) an amoeba morpho- 

 logically identical with Endolimax nana 

 from man, to which he gave the name 

 Endolimax cynomolgi. The second record 

 is that of Deschiens (19x7) who reported 

 it from 3 of 7 chimpanzees, from x of 9 

 macaques, and from x Cercopithecus mon- 

 keys at the Pasteur Institute in Paris. 

 He transferred the infection from chim- 



