Trichuriasis and low-iron status in schoolchildren from Northwest Mexico.

BACKGROUND/OBJECTIVES: The aim of this study was to investigate the association between trichuriasis and iron status in rural schoolchildren from Northwest Mexico. SUBJECTS/METHODS: A total of 73 schoolchildren (37 boys, 36 girls) between the ages of 6 and 10 years were voluntarily recruited from the public primary school of the rural community of El Higueral in Culiacan, Sinaloa (Northwest Mexico) for a cross-sectional study with a longitudinal follow-up of 5 weeks. Data were collected on socioeconomic status, anthropometry, haematological and biochemical indices of iron status, daily iron intake, and prevalence and intensity of trichuriasis. Multiple regression models, independent t-test and paired t-test were used to analyse the association between trichuriasis and iron status in cross-sectional and longitudinal samples, respectively. Adjusted models were tested for linear regression assumptions using residual plots. RESULTS: The mean age of the Trichuris-free and Trichuris-infected groups was 7.7±1.3 and 7.7±1.5 years respectively (P=0.92). The height for age was significantly higher in the Trichuris-free group than the Trichuris-infected group (P=0.02). No differences were found in the socioeconomic variables between the two groups. At baseline, significantly higher concentrations of haemoglobin, haematocrit, blood cell count (RBC) and serum iron were measured in the Trichuris-free group compared with the Trichuris-infected children (P<0.05). An association was found between trichuriasis and haemoglobin adjusted for socioeconomic variables, age and sex. Haemoglobin, RBC and serum ferritin concentrations were significantly increased in the infected children 5 weeks after treatment (P<0.05). CONCLUSIONS: Trichuriasis could be a risk factor for low-iron status in the schoolchildren of Northwest Mexico.

Prevalence and intensity of intestinal parasitic infections in relation to nutritional status in Mexican schoolchildren.

Undernutrition and intestinal parasitic infections affect childhood development and morbidity in many developing countries. Undernutrition may increase susceptibility to parasitic infections which in turn impair the nutritional status of the host. The relationship between intestinal parasitic infections and nutritional status in 400 Mexican schoolchildren was investigated. More than half of the children in the study showed intestinal parasites and polyparasitism. The prevalence of helminth infections was significantly higher in Oaxaca than in Sinaloa (P < 0.05). Z scores for weight-for-age (WA) and height-for-age (HA) were much lower in children of Oaxaca than in Sinaloa (P < 0.001). A significantly higher Z score for weight-for-height (WH), WA, and HA were found in non-infected versus infected children (P < 0.05). Higher prevalences of intestinal infections were found in children with lower HA and WA than in normally nourished children (P < 0.05). Higher intensities of Ascaris lumbricoides and Trichuris trichiura were found in the schoolchildren of Sinaloa than in Oaxaca (P < 0.01). Negative and significant associations were found between Hymenolepis nana and T. trichiura infection (eggs per gram) and nutritional status. Intestinal parasitic infections may be regarded as main risk factors associated with poor nutritional status in Mexican schoolchildren.

Intermittent iron supplementation regimens are able to maintain safe maternal hemoglobin concentrations during pregnancy in Venezuela.

Daily iron supplementation programs for pregnant women recommend amounts of iron that are considered by some to be excessive, and either lower-dose or less frequent iron supplementation regimens have been proposed. A randomized, placebo-controlled study was performed to assess and compare the relative effectiveness of a weekly (WS) or twice weekly (TW) iron supplementation schedule in maintaining or achieving hemoglobin (Hb) levels at term considered to carry minimal maternal and fetal risk (90-130 g/L). Pregnant women (n = 116) at wk 10-30 of gestation (63 WS and 53 TW) were enrolled in the study (52 in WS and 44 TW completed the study). Women were randomly allocated to receive a 120-mg oral dose of iron as ferrous sulfate and 0.5 mg of folic acid weekly (n = 52) or 60 mg iron and 0.25 mg folic acid and a placebo twice weekly (n = 44). Hb, hematocrit, serum ferritin, and transferrin saturation were estimated at baseline and at 36-39 wk of gestation. Baseline dietary data and the presence and intensity of intestinal helminthic infections were assessed. The duration of supplementation was 14 +/- 4 wk and the median level of adherence was 60.5%. Hb concentrations improved in women following the TW regimen and in women following WS who had low baseline Hb levels. About 89% of WS women and 95% of TW women maintained Hb levels at term (between 90 g/L and 130 g/L), a range associated with optimal pregnancy outcomes. One woman in the TW group exhibited higher Hb levels that potentially carried perinatal risk (>130 g/L). Intermittent iron and folic acid supplementation may be a valid strategy when used as a preventive intervention in prenatal care settings.