23,5 Leach et al.: Hookworm Infestation 493 



Assuming 4 per cent as a liberal normal high eosinophile 

 count, only nine cases will be seen to present a normal eosino- 

 philia. A number of very high counts were found, the highest 

 being 33 per cent. Ten of the counts made before treatment 

 were above 20 per cent. 



This is in sharp contrast to the blood picture presented by 

 the group of subjects in Cebu who were suffering from ad- 

 vanced hookworm disease, recently studied by us, (8) in which 

 the ansemia was profound and in none of whom did we find an 

 eosinophile count above 7 per cent. 



In the majority of the subjects infested with hookworm, there 

 was a distinct lowering of the eosinophiles during the two 

 months following treatment. This was particularly noticeable 

 in many of the cases that showed a high percentage of eosino- 

 philes on the initial count. In subjects who gave low original 

 counts, there are a few instances in which a rise is recorded. 

 In some of these instances, it will be seen that microscopic ex- 

 amination had shown the men to have retained their infections 

 after treatment. Some of these persistent positives may have 

 been men in whom an infection was developing at the time of 

 their admission to the prison, for they came into our hands 

 almost immediately after commitment. It also must be borne 

 in mind that very few of the men were cleared of their entire hel- 

 minthal infection, Ascaris and Trichuris persisting in many 

 cases. Nevertheless, twenty-five of the examinations made two 

 months after treatment show a normal eosinophilia (4 per cent 

 or less). The highest percentages were found in those still 

 retaining hookworms. 



HOOKWORM DISEASE 



None of the subjects studied in this series presented a clinical 

 picture that could be regarded as one of extreme hookworm 

 disease. In fact, practically 90 per cent of the men showed no 

 symptom that could be attributed to hookworm infestation. 

 Moreover, in the cases in which we were inclined to suspect the 

 presence of hookworm ansemia the improvement in the blood 

 picture and general physical condition of the men must be inter- 

 preted with considerable caution, as we shall show by the cases 

 of two uninfected men. It must be borne in mind that nearly 

 all the men studied were drawn from the lower walks of life 

 and presented the familiar undernourished condition that is 

 characteristic of natives of Malaysia. In the group of nine men, 

 protocols of whose cases we shall give below, eight were laborers. 



