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General and Specific Sanitation . 

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NO. 2753, VOL. I IO] 



General and Specific Sanitation. 



ALTHOUGH hookworm infection (anchylostom- 

 iasis) is so rare in this country as to be un- 

 known except among miners, the principles governing 

 its control give an illustration of the relationship 

 between specific and general control over infection, 

 which is not without value for British hygienists. 

 For this reason a monograph recently issued by the 

 Rockefeller Institute for Medical Research x is deserv- 

 ing of attention. Hookworm disease is chiefly a rural 

 disease in Brazil as elsewhere, and is most prevalent 

 where there is complete disregard of elementary sani- 

 tation, especially in warm climatic conditions, which 

 favour the life of the hookworm embryo in the soil, 

 and encourage workpeople to go barefooted. 



Dr. Smillie's investigation shows that hookworm 

 disease is most common in the ages between fifteen and 

 forty. It may be correctly described as an industrial 

 disease, as it occurs chiefly in unshod field-workers. 

 This fact comes out more clearly when a distinction 

 is drawn, as it should be, between hookworm infection 

 and hookworm disease. The importance of this dis- 

 tinction is gradually becoming appreciated in public 

 health. In diphtheria it forms an essential considera- 

 tion ; and rational measures cannot be devised for 

 the prevention of tuberculosis, which have no regard 

 for this distinction. In male children under ten years 

 of age the average number of intestinal hookworms 

 per person was 39, increasing to 169 between ten and 

 twenty, and over 200 in men between twenty and forty 

 years old. The injury to health occurs chiefly in the 

 persons showing heavier incidence of intestinal worms. 



The work of Looss and his successors proved that the 

 chief mode of hookworm infection is through the skin, 

 by its contact with faecally contaminated moist earth, 

 the mouth being an incidental and altogether unim- 

 portant channel of infection. This important fact in 

 natural history suggests the two chief methods of control 

 of the disease, the provision of latrines and covering 

 for the feet. The third line of action, that of treat- 

 ment of infected persons, has relatively smaller import- 

 ance ; and in Dr. Smillie's judgment treatment may 

 properly be limited to field-workers, and may be dis- 

 regarded for persons under five and over fifty-five years 

 of age. Hookworm disease being an industrial malady, 

 the construction of latrines in the working fields as well 

 as domestically is indispensable if the disease is to be 

 controlled ; and the difficulty of reform in this direction 

 is seen in the statement that there are practically no 

 latrines in rural Brazil. As regards the second method 

 of control, it has been found that the use of a crude pair 



1 " Studies on Hookworm Infection in Brazil, 1918-20." Second paper by 

 Dr. Wilson G. Smillie (Monographs of the Rockefeller Institute for Medical 

 Research, No. 17, May 12, 1922). 



