32 HUMAN INTESTINAL PROTOZOA IN THE NEAR EAST 



detention of men who would be otherwise returning to duty. It 

 is not of vital importance at the present time that all convalescents 

 any more than all healthy troops should be examined for E. histo- 

 lytica infections. The quick return to duty is far more important. 

 Examination is only necessary in the case of men who are still ill 

 and unable to return to duty. A man should be regarded as 

 clinically fit if he shows no sign of the disease from which he 

 suffered, is able to take full diet and undertake light duty and at 

 the same time passes a normal stool, that is to say a stool which is 

 macroscopically normal. It seems to us quite unnecessary and a 

 waste of time to examine the healthy stools of such men with the 

 object of detecting E. histolytica or other protozoal infections, for 

 the finding of E. histolytica cysts in these men does not mean that 

 they have had or are soon likely to have amoebic dysentery any 

 more than the healthy men who have not been invalided. Further, 

 although we fully recognize that the convalescent cyst carrier may 

 be a source of danger to others, the same is true of the much larger 

 number of healthy and unsuspected cyst carriers whom it is, of 

 course, quite impossible to detect, far less examine. 



(d) The Length of Control Necessary after Treatment. 



As there cannot be any question at the present time of elimin- 

 ating all the E. histolytica carriers from amongst the troops it is 

 unnecessary to control any healthy carriers which have accidentally 

 come to light, after the completion of a course of treatment. As 

 will be shown in the section devoted to the treatment of healthy 

 carriers, it is possible to cure the infection in practically every 

 instance by the combined subcutaneous and oral administration of 

 emetin. This refers only to the healthy carriers, the great majority 

 of whom have no history of dysentery. When a history of 

 dysentery has been obtained it is in most instances impossible to 

 decide whether it was bacillary or amoebic. There are, however, 

 unhealthy carriers. These are cases which suffer from chronic 

 amoebic dysentery. They have repeated attacks when blood and 

 mucus appear in the stool along with active amoabse with included 

 red blood corpuscles. Alternating with these are periods when 

 dysentery is not evident and the stools may or may not be normal, 

 though generally they are soft and mucoid. Microscopic examina- 

 tion at this time reveals the same condition (cysts and free amoebae) 

 as in the healthy carrier. These chronic amoebic dysenteries are most 

 ; difficult to cure and, as will be shown below, the majority relapse 



