E. histolytica: latency and relapse 



quate, who tends to be faddy and irritable, who is vaguely 

 ill, without knowing what is wrong with him ; the second 

 the fat jovial type, with good food assimilation, a bon 

 viveur, who soon discovers, however, that indulgence in 

 'short drinks' at the club bar is apt to be followed by 

 trouble. Together with minor ulceration of the colon 

 mucosa by the entamoebse goes a train of ill-defined symp- 

 toms," which they describe in detail under the subheads, 

 irregularity in the state of the bowels, pain, fever, bac- 

 terial embolism, and absorption of poisonous pressor 

 bases from the ulcerated gut. 



Craig (1927) states that his experience indicates that 

 more than 50 per cent of the so-called carriers of E. his- 

 tolytica present some symptoms apparently caused by 

 the presence of these amoebae in the intestine. These 

 symptoms are largely confined to the digestive and nerv- 

 ous systems. Constipation and diarrhea are perhaps the 

 most common; lack of appetite is very frequent and is 

 associated with loss of weight ; and evanescent neuralgic 

 pains in the lower portion of the abdomen and other 

 symptoms are characteristic. The symptoms referable to 

 the nervous system are of the neurasthenic type. A mild 

 degree of anemia and occasional subnormal temperature 

 may occur. Craig expresses belief in the routine examina- 

 tions of stools and in efforts to cure carriers. 



(2) Latency and relapse. Latency in amoebiasis 

 exists only in the sense that parasites may be present with- 

 out the appearance of symptoms. If fecal specimens from 

 hosts in which E. histolytica is living in a 'latent" con- 

 dition are examined daily, eventually cysts or tropho- 

 zoites will be found. As noted above (p. 108) a host 



III 



.....^ J. 



