Early Helminth Infections Are Inversely Related to Anemia, Malnutrition, and Malaria and Are Not Associated with Inflammation in 6- to 23-Month-Old Zanzibari Children

Abstract

Abstract. Helminths aggravate anemia and malnutrition among school children. We studied this association in a crosssectional study of 6-to 23-month-old Zanzibari children ( N = 2322) and a sub-sample of 690 children matched on age and helminth infection status. Ascaris , hookworm, and Trichuris infections were diagnosed along with recent fever, malaria infection, mid-upper arm circumference (MUAC) and hemoglobin concentration (Hb). Alpha-1-acid glycoprotein (AGP), C-reactive protein (CRP), height, and weight were measured in the sub-sample. Infected children had higher Hb (β = 5.44 g/L, P < 0.001) and MUAC-for-age Z score (β = 0.30 Z, P < 0.001) compared with uninfected children after adjusting for covariates. Although helminths were not associated with inflammation, their association with Hb or MUAC-for-age Z score was modified by inflammation. Malaria-infected children were less likely to be infected with helminths (adjusted odds ratios 0.63 [95% confidence interval: 0.49, 0.81]). Non-anemic, better nourished, or non-malaria-infected children may be more exploratory of their environments and therefore increase their exposure to soil-transmitted helminths.

Soil-Transmitted Helminth Infection and Nutritional Status Among Urban Slum Children in Kenya

“…26 Studies in Zanzibar, similarly, found no association between helminth infection early in life and anemia or malnutrition, which is hypothesized to be secondary to increased environmental exploration and thus, increased exposure to STH by better-nourished children. 27 However, in a 12-month deworming trial of children 6-71 months of age, mebendazole improved anemia only in children 24 months of age, suggesting that young children may still benefit from deworming, because they are at higher risk of anemia, although at lower intensity of helminth infection. 5 We found no evidence of helminth-induced inflammation and in fact, a negative association between any STH infection and AGP among SAC.…”

Epidemiology of Hookworm Infection in Kintampo North Municipality, Ghana: Patterns of Malaria Coinfection, Anemia, and Albendazole Treatment Failure

“…Our findings are consistent with previous reports, including a study in Zanzibar that reported a larger negative effect on blood hemoglobin levels in children with malaria infection alone than in those who were coinfected with helminths. 41 Similarly, in a study of Peruvian school children, there was a significant drop in hemoglobin during a symptomatic infection with Plasmodium vivax among children who were not infected with intestinal helminths, whereas anemia was not exacerbated in those harboring worms. 51 By contrast, others have reported varying increases in the risk of anemia with malaria and helminth coinfection across various age groups.…”

“…For example, a cross-sectional study of school-age children in Tanzania found a higher prevalence of helminth infection (hookworm or Schistosoma mansoni ) among children with P. falciparum , 40 although a comparable study of younger children (6-23 months) found a lower prevalence. 41 A deworming trial in Nigeria showed a significantly reduced rate of increase in malaria prevalence and intensity among children who were treated with albendazole. 42 Two studies in Thailand found that Ascaris coinfection was associated with a decreased risk of cerebral malaria, 43,44 although a prospective study by the same authors found a higher risk.…”

Soil Transmitted Helminth Infections in Medan: a cross-sectional study of the correlation between the infection and nutritional status among elementary school children

“…This could be due to the fact that the children's nutritional status is affected by a variety of factors, not only the presence of STH infection. Studies conducted by Kung'u et al also showed similar results [37].…”