The contribution of hookworm and other parasitic infections to haemoglobinand iron status among children and adults in western Kenya

A cross-sectional study of 729 children and adults in western Kenya investi gated the impact of infection with hookworm, Ascaris lumbricoides, Trichuri s trichiura, Schistosoma mansoni and malaria on iron status. In bivariate a nalyses, hookworm intensities as low as 300 eggs/g of faeces were negativel y related to levels of haemoglobin (Hb) and serum ferritin (SF). Malaria pa rasitaemia was negatively related to Hb and positively related to SF, while S. mansoni intensities were negatively related to SE Multivariate regressi on analysis was done to identify predictors of Hb and SF levels. In childre n, age (in years) was the only predictor for Hb (B=1.7 g/L) and only malari a parasitaemia (negative, light, moderate, heavy) was retained in the model for log(10) SF (B=0.097 mu g/L). In adults, hookworm infection and malaria parasitaemia together with age, sex, pregnancy, SF levels <12 mu g/L and e levated body temperature were significant predictors of low Hb. The regress ion coefficient for hookworm egg count (for increments of 100 eggs/g) was - 1.3 g/L. Significant interactions between sex and age and between sex and m alaria parasitaemia were revealed. Age and malaria parasitaemia were signif icant predictors only among females, with a regression coefficient for mala ria parasitaemia of -6.9 g/L. The regression coefficient for hookworm did n ot change when SF <12 mu g/L was taken out of the model, indicating that th e effect of hookworm cannot be explained by low iron stores alone. Using SF as the dependent variable, hookworm and S. mansoni intensities together wi th age and sex were retained in the model. The regression coefficients for hookworm egg count (increments of 100 eggs/g) and S. mansoni egg count (inc rements of 10 eggs/g) were -0.011 mu g/L and -0.012 mu g/L, respectively. I ron deficiency was a problem in this population and hookworm infections con tributed significantly to this situation.