Moderate- And Low-Intensity Co-Infections by Intestinal Helminths and Schistosoma Mansoni, Dietary Iron Intake, and Anemia in Brazilian Children

Abstract

Abstract. To determine the role of moderate-and low-intensity infections with Schistosoma mansoni and intestinal helminths (hookworm, Trichuris trichiura, Ascaris lumbricoides) on the prevalence of anemia and their relationship to iron consumption, a cross-section of 1,709 children in rural Brazil was studied. All participants were selected for infection with one or multiple helminthic parasites, and demographic, anthropometric, and dietary intake were surveyed. The prevalence and intensity were as follows: hookworm infection, 15.7% and 8.6 eggs/g; T. trichiura, 74.8% and 190.5 eggs/g; A. lumbricoides, 63% and 1,905.5 eggs/g; S. mansoni, 44.5% and 60.3 eggs/g. There was no increase in odds ratio for anemia with any combination of intestinal helminths without S. mansoni infection. By logistic regression, the odds ratio for having anemia when infected with S. mansoni and two intestinal helminths was 1.7 (95% CI, 1.1-2.5) and for S. mansoni and three intestinal helminths was 2.4 (95% CI, 1.2-4.6) compared with children with a single parasite species. Children with an adequate intake of iron had no increased odds of anemia independent of the combination of parasite infections.

Schistosoma mansoni Morbidity among School-Aged Children: A SCORE Project in Kenya

“…Neither Trichuris nor hookworm infections were independently associated with anemia, however S. mansoni infection was associated with anemia, consistent with other studies both before and after controlling for other predictors. 11,19,[38][39][40] Though it may lack specificity in relation to other conditions common in developing countries, our data support the role of anemia as a good morbidity indicator for schistosomiasis, given that it can be easily measured and there was a large absolute difference in prevalence of anemia in children infected and uninfected with S. mansoni.…”

Soil-Transmitted Helminthiasis in Laos: A Community-Wide Cross-Sectional Study of Humans and Dogs in a Mass Drug Administration Environment

“…Recent studies in the Philippines demonstrated that low-to-moderate intensity multiple infections were associated with anemia, 5,31 although schistosomiasis seemed to be the dominant controlling infection, as was observed in a similar study in Brazil. 32 These results have not been supported by studies conducted in Africa, where schistosomiasis is also prevalent, 33,34 although these later studies could be complicated by administration of drugs to control helminthiasis. Less clear again is the impact of multiple infections on cognitive function.…”

Trichuriasis and low-iron status in schoolchildren from Northwest Mexico

“…A combination of these factors along with low dietary iron and increased requirements in infancy, adolescence and pregnancy can contribute to IDA (Fomon et al, 2003). The association between trichuriasis and IDA has been well documented (Otto, 1935;Burrows and Lillis, 1964;Layrisse et al, 1967;Robertson et al, 1992;Ramdath et al, 1994;Brito et al, 2003Brito et al, , 2006, as well as an association of IDA with premature delivery, low birth weight, altered gastrointestinal function, perinatal morbidity, decreased growth (Garn et al, 1981;Steer, 2000;Hamalainen et al, 2003), changes in behaviour, mental and motor development (Beard, 2003), lower iron transference to the foetus (Ramakrishnan, 2001), reduced physical work capacity (Haas and Brownlie, 2001) and an impaired immune system (Dallman, 1987). In Mexico, trichuriasis has remained an important human helminthiasis since the 1950s (Carrada-Bravo, 1988;Tay et al, 1995).…”