254 ^^6 Philippine Journal of Science ms 



itary conditions, the percentage of morbidity due to this cause 

 is not so high at the present time, at least in the city of Manila. 

 Gauducheau (1912), at the last biennial congress of the Far 

 Eastern Association of Tropical Medicine, stated that amoe- 

 biasis, under the form of dysentery and abscess of the liver, causes 

 nearly half of the deaths of Europeans at Tonkin, Indo China. 

 While it is impossible to give accurate statistics, owing to the 

 fact that the different types of dysentery are not usually sepa- 

 rated in the reports of infectious diseases, it is probable that, 

 except where modified by sanitation, this disease holds a more 

 or less similar position in the morbidity and mortality statistics 

 of other tropical countries. 



Notwithstanding that amcebse have been associated with a 

 certain type of dysentery since 1875, the etiologic relation of 

 these organisms to this disease has been the most controverted 

 question in tropical medicine. Between the extreme views that 

 amoebse combat disease and are the true guardians of man's 

 health (Cassagrandi and Barbagallo, 1895), on the one hand; 

 and, on the other hand, that all amoebae are or may become 

 pathogenic (Musgrave and Clegg, 1904), every intermediate 

 opinion of the etiologic relation of amoeboid organisms to en- 

 demic tropical dysentery has been expressed. However, in 

 recent years it is becoming more and more generally accepted 

 that amoebse do play a role in the production of this type of 

 dysentery; yet dissenters from this view still appear from time 

 to time (Tanaka, 1910, and Duncan, 1912), and it has not been 

 definitely proved whether this role is primary or secondary. 



Our knowledge of the specific amoeba concerned in the produc- 

 tion of this disease is equally uncertain. Eighteen species rep- 

 resenting 4 genera of amoeboid organisms ^ have been described 

 as parasites in the intestinal tract of man. Of these at least 5 ' 

 have been definitely stated to be more or less pathogenic, and 

 there exists no conclusive evidence to exclude the other 11 from 

 the list of pathogenic species. Moreover, the observations and 



' Atnosba sp. Noc (1909), A. Umax (Vahlkampfia) Chatton and Lalung- 

 Bonnaire (1912), Entamosba coli Schaudinn (1903), E. histolytica Schau- 

 dinn (1903), E. undulans Castellani (1905), E. tropicalis Lesage (1905), E. 

 tetragena Viereck (1907), E. phagocytoides Gauducheau (1908), E. minuta 

 Elmassian (1909), E. nipponica Koidzumi (1909), E. tetragena (non E. 

 tetragena Viereck) Akashi (1911), E. sp. Akashi (1911), E. williamsi 

 Prowazek (1911), E. brasiliensis Beaurepaire Aragao (1912), E. hartmanni 

 Prowazek (1912), E. butschlii Prowazek (1912), Paramceba hominis Craig 

 (1906), and Chalamydophrys stercorea Cienk. (Schaudinn, 1903). 



' Amosba sp. Noc, Enta'rnceba histolytica Schaudinn, E. tetragena Viereck, 

 E. minuta Elmassian, and Paramceba hominis Craig. 



