AMCEBIC DYSENTERY 157 



It is not known definitely how nor where the 

 amoeba of dysentery multiply outside of the body, 

 although raw foods and water carry the organisms. 

 It is said that the sand filtration of water which 

 effectually removes the typhoid and cholera organ- 

 isms does not withhold dysentery amoebae. Mon- 

 keys in confinement contract amoebic dysentery 

 by natural conditions, and cats and other animals 

 have been infected by introducing the amoebae into 

 the rectum, and by feeding them the spores. 



Amoebae are found in the intestines of healthy 

 persons which are called entamoeba coli; these mul- 

 tiply by both fission and spore-formation, and are 

 considered an entirely distinct species. 



A class of protozoa known as trypanosomes cause 

 a number of diseases common to horses, cattle, and 

 wild animals in South Africa, as well as the terrible 

 "sleeping sickness" among human beings. 



Transmission takes place through the bites of 

 insects: rat fleas, lice, ticks, and the "tsetse-fly" 

 which carries the infection of "sleeping sickness." 

 It is believed that the parasites — trypanosomes — 

 exist in the bodies of the larger wild animals, and are 

 always transmitted to man and the domestic animals 

 by the bites of flies or other insects. 



