The effect of hookworm infection and urinary scistosomiasis on blood hemoglobiin concentration of schoolchildren living in northern Mozambique / Infecções por ancilostomídeos e Schistosoma haematobium e sua correlação com a concentração sanguínea de hemoglobina em crianças moçambicanas

This study aims to assess the association between schistosomiasis and hookworm infection with hemoglobin levels of schoolchildren in northern Mozambique. Through a cross-sectional survey, 1,015 children from five to 12 years old in the provinces of Nampula, Cabo Delgado and Niassa were studied. Hookworm infection and urinary schistosomiasis were diagnosed, through Ritchie and filtration methods, with a prevalence of 31.3% and 59.1%, respectively. Hemoglobin levels were obtained with a portable photometer (Hemocue®). The average hemoglobin concentration was 10.8 ± 1.42 g/dL, and 62.1% of the children presented levels below 11.5 g/dL, of which 11.8% of the total number of children had hemoglobin levels below 9 g/dL. A multiple linear regression analysis demonstrated negative interactions between hemoglobin levels and ancylostomiasis, this being restricted to the province of Cabo Delgado (β = -0.55; p < 0.001) where an independent interaction between hemoglobin levels and urinary schistosomiasis was also observed (β = -0.35; p = 0.016). The logistical regression model indicated that hookworm infection represents a predictor of mild (OR = 1.87; 95% CI = 1.17-3.00) and moderate/severe anemia (OR = 2.71; 95% CI = 1.50 - 4.89). We concluded that, in the province of Cabo Delgado, hookworm and Schistosoma haematobium infections negatively influence hemoglobin levels in schoolchildren. Periodical deworming should be considered in the region. Health education and improvements in sanitary infrastructure could achieve long-term and sustainable reductions in soil-transmitted helminthiases and schistosomiasis prevalence rates.

Este estudo tem como objetivo avaliar a relação entre a ancilostomíase e a esquistossomíase urinária com as concentrações sanguíneas de hemoglobina em crianças escolares no norte de Moçambique. Em estudo transversal, 1.015 crianças com idade entre cinco e 12 anos foram incluídas, nas Províncias de Nampula, Cabo Delgado e Niassa. A ancilostomíase e a esquistossomíase urinária foram diagnosticadas através das técnicas de Ritchie e de filtração da urina, respectivamente; prevalências de 31,3% e 59,1% foram observadas. As concentrações sanguíneas de hemoglobina foram obtidas com um fotômetro portátil (Hemocue). A concentração média de hemoglobina foi 10,8 ± 1.42 g/dL, 62,1% das crianças apresentaram concentração abaixo de 11,5 g/dL e 11,8% apresentaram nível abaixo de 9 g/dL. A regressão linear múltipla demonstrou interações negativas entre os níveis de hemoglobina e i) a infecção por ancilostomídeos (β = -0,55; p < 0,001) e ii) a esquistossomíase urinária (β = -0,35; p = 0,016), ambas associações restritas à Província de Cabo Delgado. Também em Cabo Delgado, o modelo de regressão logística demonstrou que a infecção por ancilostomídeos representa um preditor de anemia leve (OR = 1,87; 95% CI = 1,17-3,00) e anemia moderada/grave (OR = 2,71; 95% CI = 1,50 - 4,89). O estudo conclui que em Cabo Delgado, Moçambique, as infecções por ancilostomídeos e Schistosoma haematobium estão significativamente associadas a uma menor concentração sanguínea de hemoglobina em crianças em idade escolar. A administração periódica de anti-helmínticos deve ser feita regularmente. Melhorias na infraestrutura sanitária das regiões estudadas são as medidas mais eficazes para controle destas parasitoses.

Prevalence of anaemia and worm infestation in tribal areas of Madhya Pradesh.

The study was conducted among school going children (6-14 years) of Baiga, Abuihmadia and Bharia tribes of Madhya Pradesh to assess the prevalence of anaemia and intestinal parasitic infestation among themselves. A total of 776 school going children were included in the study of whom blood samples of all and stool samples of 409 were collected. Their haemoglobin was measured and stool samples were examined under microscope for ova and cysts. The results revealed that 30.3% of the children had severe anaemia (Hb < 7g/dl) and 50% children had intestinal parasites. The most common parasites were hookworn (16.3%) and A lumbricoides (18.5%). Though hookworm ova loads indicated mild to moderate infestation in most of the children, the continued presence of worms in marginally nourished children could contribute significantly to blood loss in the intestine with resultant anaemia.

Eosinophilia, anemia and parasitism in a rural region of northwest Thailand.

Parasitic infections are prevalent in Thailand. The parasites' relationship with anemia and eosinophilia has been rarely reported due to limited health care access, especially in rural areas. We studied the prevalence and relationship between eosinophilia, anemia and parasitism in 169 Thai-Karens from Mae Lamung and Mae Chan subdistricts, Umphang district, Tak Province, using an automated complete blood counter, and microscopic examination for intestinal parasites and microfilaria. In Mae Chan, 5 individuals were microfilaremic, 72% of individuals examined were infected with at least one kind of intestinal parasites, and 50% were anemic, with normal mean red cell volume (MCV). In Mae Lamung, 46% were parasitized (Triteeraprapab et al, 1997) but none were microfilaremic or anemic. In both populations, eosinophilia was prevalent (77%). Hookworm infection was found to be significantly associated with eosinophilia, but not anemia nor microcytosis of red cells.

Zinc in the pathogenesis of hookworm anaemia.

Serum zinc levels in 90 patients with hookworm infection were compared with those of 26 uninfected controls. The severity of infection was graded in terms of haemoglobin levels as well as egg loads. The results showed that the serum zinc levels in anaemic patients with hookworm infection were significantly lower than those of the controls (p less than 0.01).

The effect of riboflavin on the hematologic changes in iron supplementation of schoolchildren.

A supplementation trial was carried out in 101 children, 6-12 years of age, in 3 primary schools in a rural area. Their hemoglobin level and PCV (mean +/- SD) were 11.64 +/- 1.21 g/dl and 0.356 +/- 0.028 respectively, 74% of them were anemic and the hemoglobin level were correlated with the MCHC (P < .01) . Fifty-one per cent of them had hookworm infection and all those with hemoglobin levels below 10 g/dl had hookworm infection, but there was no difference in mean hemoglobin level between those with hookworm infection and those without. The children were divided into 3 groups: Group I comprising 39 children who received placebo tablest; Group II of 33, who received ferrous sulphate (60 mg elemental iron); Group III of 29, who received ferrous sulphate (60 mg elemental iron) with riboflavin (6mg). Each child received one tablet after lunch on schooldays and evaluation was carried out after receiving 80 to 90 tablets. The mean hemoglobin change of Group II was 0.60 g/dl larger than that of Group I (P < .005) with 52% of them responding to iron. The mean hemoglobin change of Group III was 0.38 g/dl larger than that of Group II (P < .005) with 86% of them responding to iron and riboflavin. Thus additional riboflavin is beneficial in iron supplementation.

Serum and red cell folate activity and folic acid absorption in patients with hookworm infection.

Red cell and serum folate levels and folic acid absorption were studied in patients with hookworm infection. The mean value of serum folic acid level was found to be significantly lower than that of the normal subjects and 32% of cases had serum folic acid level less than 4 ng/ml. The red cell folate content in all patients studied were within the normal limits. The mean value of the folic acid absorption was also lower than that of the normal. Six out of 13 patients absorbed folic acid less than 38%, the lowest value obtained from the normal subjects. These findings indicated that there was a negative balance of folic acid in some patients with hookworm infection which was probably due to impairment in absorption.