30 HUMAN INTESTINAL PROTOZOA IN THE NEAR EAST 



be necessary to examine them regularly at stated intervals. It 

 seems, therefore, that in a country like Egypt very little can be done 

 in the way of isolating carriers of E. histolytica from amongst 

 healthy troops, and one could not possibly advise that it should be 

 undertaken on a large scale in time of war. 



(6) The Danger of Amoebic Dysentery spreading in England. 



Another aspect of the question is the possibility of the spread 

 of amoebic dysentery to countries in which the disease does not 

 already exist, and it has been suggested that troops which are to be 

 moved from an area where the disease is endemic should be 

 examined and the carriers detained. Here again the amount of 

 work which would be necessary to carry out such a project shows 

 this to be quite impossible in time of war except in the case of 

 small drafts. But in a country like England is there any real 

 danger that the disease will be spread in this manner ? Cases of 

 amoebic dysentery contracted in England are not unknown, though 

 r they are far from common. It seems very improbable that the 

 disease will establish itself there, for though it is only recently that 

 the carrier problem of amo3bic dysentery has attracted attention, it 

 must not be forgotten that carriers have been constantly entering 

 England before the present War, and that troops have often returned 

 from countries in which the disease is endemic. There have 

 undoubtedly been large numbers of carriers amongst such men, 

 though no one has considered it worth while to examine them from 

 this point of view. There must have been in the past every possi- 

 bility that the disease would establish itself in England if the 

 conditions favourable for the survival of cysts outside the body 

 and their transference to other individuals had existed. Though 

 isolated cases of infection have occurred, the disease has been 

 exceedingly rare. This failure of the disease to establish itself must 

 be the result of many factors, the most important of which are 

 \j undoubtedly the existence of a good sanitary system and the com- 

 parative absence of flies, while climatic conditions undoubtedly 

 play a prominent part. In England, even in rural districts where 

 the sanitary arrangements are often far from perfect, the infected 

 material is not spread broadcast over the land as it is in countries 

 like Egypt ; while flies, though very numerous in certain localities, 

 are never so universal as they are in warm countries, which are the 

 natural homes of the disease. 



With the establishment of large camps in rural districts of 

 England, we may expect some temporary increase in the local cases 



