Iron deficiency and helminth
infections are two common conditions of children in developing countries. The consequences of helminth
infection in young children are not well described, and the efficacy of low dose
iron supplementation is not well documented in
malaria-endemic settings. A 12-mo randomized, placebo controlled, double-blind trial of 10 mg daily
iron and/or
mebendazole (500 mg) every 3 mo was conducted in a community-based sample of 459 Zanzibari children age 6-71 mo with
hemoglobin > 70 g/L at baseline. The trial was designed to examine treatment effects on growth,
anemia and appetite in two age subgroups.
Iron did not affect growth retardation,
hemoglobin concentration or mild or moderate
anemia (
hemoglobin < 110 g/L or < 90 g/L, respectively), but
iron significantly improved serum
ferritin and erythrocyte
protoporphyrin.
Mebendazole significantly reduced wasting
malnutrition. but only in children <30 mo old. The adjusted odds ratios (AORs) for
mebendazole in this age group were 0.38 (95% CI: 0.16, 0.90) for weight-for-height less than -1 Z-score and 0.29 (0.09, 0.91) for small arm circumference. In children <24 mo old,
mebendazole also reduced moderate
anemia (AOR: 0.41, 0.18, 0.94). Both
iron and
mebendazole improved children's appetite, according to mothers' report. In this study,
iron's effect on
anemia was limited, likely constrained by
infection,
inflammation and perhaps other nutrient deficiencies.
Mebendazole treatment caused unexpected and significant reductions in wasting
malnutrition and
anemia in very young children with light
infections. We hypothesize that incident helminth
infections may stimulate inflammatory immune responses in young children, with deleterious effects on
protein metabolism and erythropoiesis.