Hemoglobin Determination in Hookworm Disease Case-Finding 1

Abstract

Summary 1. The selection of anemic individuals has been recommended as an initial step in hookworm disease case finding. The present study is an attempt to establish criteria for the identification of anemia and to test their applicability to the practical hookworm control program. 2. The range in hemoglobin levels with reference to sex, age and season was determined for 1,174 economically favored urban school children who were essentially free of hookworm infection. During the same periods hemoglobin determinations were made on 1,307 rural school children in a nearby county where hookworm infection was highly endemic. 3. On the basis of findings on the urban group, 10–10.5 grams for ages six to ten and 11–11.5 grams for older children were considered to be borderline levels, and by these criteria approximately three per cent of the rural group were anemic and five to seven per cent were borderline cases. 4. Stool examinations including egg-counts on the 297 positives were obtained on 544 subjects. Among them were 40 anemic and 74 borderline cases. Three of the anemics and 15 of the borderline cases were negative for hookworm. 5. Almost all subjects with egg-counts above 20,000 per cc of stool were in the anemic or borderline classes but half of those with counts of 5,000–20,000 per cc had hemoglobins above the borderline level. Among the younger children, those with light hookworm infections had lower hemoglobins than the uninfected ones. 6. The conclusion is reached that hookworm disease case-finding based on egg-counts restricted to anemic individuals will discover most of the extremely heavy infections. However, it will fail to detect an important group of individuals whose hemoglobin levels, although markedly reduced by hookworm infection, are still within the range of normal.