PART I. INCIDENCE 25 



I-cysts, is sufficient to account for the spread of these infections to 

 British troops in and around Alexandria, especially when we 

 remember the part played by flies in the transportation of these 

 protozoa and the manner in which the natives deposit their faeces 

 broadcast over the land. 



We examined a certain, though small, number of actual human 

 faecal deposits collected from corners and open spaces in Alexandria 

 and found, as was to be expected, that the percentages of infections 

 were not lower than those obtained amongst the prisoners in 

 Hadra Prison. It is evident, therefore, that the native carrier is 

 the source of infection for E. histolytica and other intestinal 

 protozoa. The scarcity of flagellates amongst these natives has 

 already been mentioned, and it may be that in the case of 

 the flagellates some other reservoir exists, possibly some animal 

 associated with man. It is noteworthy that we have found 

 both trichomonas and lamblia in cats in Alexandria, while these 

 flagellates are known to occur in rats and mice. So far no 

 proof has been obtained as to the identity of these with the 

 parasites of the human intestine. 



To return to the prisoners of Hadra Prison, it is interesting that 

 very few indeed of these men had any sign of intestinal disorder. 

 They had a uniform diet, and this had the effect of producing a 

 curious uniformity and monotony in the character of the stool. In 

 the case of only three of the men could the stool be described as 

 abnormal, and in one of these, a soft unformed stool, tetramitus was 

 found. 



A classification of the prisoners examined was made according 

 to the length of time they had been in prison. It was found that 

 the infections amongst those who had been in jail one week only or 

 under this time were not lower than amongst those who had served 

 longer periods. It was evident that the infections could not be the 

 result of life in jail in other words, that the infections were not 

 jail infections. This is borne out also by the result of our examina- 

 tion of faecal deposits taken at random about the town which has 

 been referred to above. 



(/) Native Cooks. In addition to the examination of native 

 prisoners in Hadra Prison, we examined a series of eighty-seven 

 native cooks who were employed in an Army bakery, and the Hotel 

 Metropole, which was used as a restaurant by soldiers employed in 

 Alexandria. The natives were of a better class than the native 

 prisoners in Hadra Prison, and their infections conform more to the 

 type found amongst the British troops. The amoebic infections 



