Search

Background: Epigenetic changes in response to allergen exposure are still not well understood. The aim of this study was to evaluate histone acetylation levels in peripheral blood leukocytes from humans naturally infected by intestinal parasites and perennially exposed to house dust mites (HDM)., Methods: Peripheral blood mononuclear cells (PBMCs) were isolated by gradient centrifugation from 20 infected and 21 non-infected individuals living in a rural/village in Colombia. Histone 3 acetylation (H3Ac) and histone 4 acetylation (H4Ac) levels were measured in six immune genes previously associated with helminth immunity by chromatin immunoprecipitation (ChIP)-quantitative PCR. Then we analyzed the association between histone acetylation levels with total parasite egg burden and IgE levels., Results: We found an inverse correlation between H4Ac levels in the IL13 gene and egg worm burden that remained significant after adjustment by age [-0.20 (-0.32 to -0.09), p < 0.0001]. Moreover, we found significant associations between H4Ac levels in IL4 [0.32 (0.05-0.60), p = 0.02] and CHI3L1 [0.29 (0.08-0.51), p = 0.008] with the IgE levels to Ascaris lumbricoides . In addition, the levels of specific IgE antibodies to HDM were associated with H4Ac levels in the gene TNFSF13B encoding the B cell activating factor (BAFF) [0.51 (0.26-0.76), p < 0.001]. All values are presented as beta (95% CI)., Conclusion: Histone acetylation levels at key type-2 immune genes in humans were modified by nematode infection and HDM allergens and are associated with the intensity of the IgE response., (Copyright © 2020 Zakzuk, Acevedo, Harb, Eick, Renz, Potaczek and Caraballo.)

Background: Animal and human studies indicate that definitive host helminth infections may confer protection from allergies. However, zoonotic helminths, such as Toxocara species (spp.), have been associated with increased allergies., Objective: We describe the prevalence of Toxocara spp. and Ascaris spp. seropositivity and associations with allergic diseases and sensitization, in 2 generations in Bergen, Norway., Methods: Serum levels of total IgG4, anti-Toxocara spp. IgG4 and Ascaris spp. IgG4 were established by ELISA in 2 cohorts: parents born 1945-1972 (n = 171) and their offspring born 1969-2003 (n = 264). Allergic outcomes and covariates were recorded through interviews and clinical examinations including serum IgEs and skin prick tests., Results: Anti-Ascaris spp. IgG4 was detected in 29.2% of parents and 10.3% of offspring, and anti-Toxocara spp. IgG4 in 17.5% and 8.0% of parents and offspring, respectively. Among offspring, anti-Toxocara spp. IgG4 was associated with pet keeping before age 15 (OR = 6.15; 95% CI = 1.37-27.5) and increasing BMI (1.16[1.06-1.25] per kg/m 2 ). Toxocara spp. seropositivity was associated with wheeze (2.97[1.45- 7.76]), hayfever (4.03[1.63-9.95]), eczema (2.89[1.08-7.76]) and cat sensitization (5.65[1.92-16.6]) among offspring, but was not associated with allergic outcomes among parents. Adjustment for childhood or current pet keeping did not alter associations with allergies. Parental Toxocara spp. seropositivity was associated with increased offspring allergies following a sex-specific pattern., Conclusions & Clinical Relevance: Zoonotic helminth exposure in Norway was less frequent in offspring than parents; however, Toxocara spp. seropositivity was associated with increased risk of allergic manifestations in the offspring generation, but not among parents. Changes in response to helminth exposure may provide insights into the increase in allergy incidence in affluent countries., (© 2017 The Authors. Clinical & Experimental Allergy Published by John Wiley & Sons Ltd.)

The aim of this study was to evaluate whether serology can be used to measure exposure of piglets to Ascaris suum during the nursery phase. Experimental infection studies were performed in which 7 groups of 10 piglets of 4 weeks of age were orally infected with either 10, 20, 40, 60, 80, 100 and 500 A. suum eggs/day during 7 consecutive weeks, mimicking a nursery phase in an A. suum contaminated environment. Serum was collected on a weekly basis to monitor seroconversion on 2 ELISA tests based on the antibody recognition of either a haemoglobin protein purified from the pseudocoelomic fluid of adult A. suum or a water-soluble complete homogenate of the 3rd stage larvae isolated from the lungs (L3-lung). A dose-dependent seroconversion was measurable with the L3-lung ELISA starting from 4 weeks post-infection onwards, whereas this was not measurable with the haemoglobin-based test. After 7 weeks, equivalent to the end of the nursery phase, the L3-lung ELISA showed a 99% specificity and a 90% sensitivity to detect exposure of piglets to A. suum, with a minimum infection level of 20 A. suum eggs per day. To further evaluate the test under field conditions, a seroprevalence study was performed by sampling 10 piglets on 68 different nursery farms in Belgium. The results showed that for 38% of the farms analysed all piglets tested seronegative, whereas for the remaining 62% of the farms the percentage seropositive piglets ranged from 10 to 100%. This indicates contamination of the nursery facilities with A. suum eggs. In conclusion, the outcome of this study shows that serology can be used to measure exposure of nursery piglets to A. suum, thereby providing an additional tool in the control of this widespread parasite., (Copyright © 2017 Elsevier B.V. All rights reserved.)

AbstractMore than 2 billion people are infected with parasites globally, and the majority have coinfections. Intestinal protozoa and helminths induce polarizing CD4 + T-helper cell 1 (Th1) mediated cytokine responses within the host. Such immune polarization may inhibit the ability of the host to mount an adequate immune response for pathogen clearance to concurrent pathogens. The current study evaluated the plasma cytokine profile in Ascaris and Giardia coinfected children compared with Giardia - and Ascaris -only infected children. Fecal samples and blood samples were collected from asymptomatic 3-year-old children living in the district of Quininde, Ecuador. Stool samples that tested positive for Giardia lamblia -only, Ascaris lumbricoides- only, or G. lamblia and A. lumbricoides coinfections were confirmed by quantitative real-time polymerase chain reaction. Plasma samples from the study subjects were used to quantitate cytokines. A total of 39 patients were evaluated. Children with coinfection had a significant decrease in Th1 cytokine production, interleukin 2 (IL-2) ( P < 0.05), IL-12 ( P < 0.05), and tumor necrosis factor alpha ( P < 0.05) compared with Giardia -only infected children. Coinfected children had an increase in IL-10/interferon gamma (IFN-γ) ratio compared with uninfected ( P < 0.05) and Ascaris alone ( P < 0.05). The increased IL-10/IFN-γ ratio in the setting of decreased Th1 cytokine response indicates Th2 polarization in the coinfected group. Reduced Th1 cytokines in children coinfected with Ascaris and Giardia may impair the host's ability to eradicate Giardia infection leading to chronic giardiasis.

Background: Soil-transmitted helminths (STHs) and Plasmodium falciparum infections remain public health problems in Cameroon. A cross-sectional study was carried out in the Mount Cameroon area to determine the prevalence and intensity of STHs and P. falciparum infections in individuals living in different agroecosystems; to assess the influence of these infections on haematological parameters; and to identify the risk factors associated with STH infections., Methods: STH and malaria parasites were detected using the Kato-Katz method and Giemsa staining of blood films, respectively. Complete blood count values were obtained using an automatic haematology analyser. Soil samples were analysed using the sucrose floatation sedimentation method. Categorical and continuous variables were compared as required and logistic regression models were used to assess the risk factors for STH infections and anaemia., Results: Of the 450 participants examined, STHs, P. falciparum and mixed co-infections were detected in 14.0, 33.3 and 5.6% of participants, respectively. Significantly higher prevalences of Ascaris (18.8%) and Trichuris (7.9%) infections were observed in participants from tea plantation areas compared to those from banana and palm plantation areas, with similar trends in egg density. P. falciparum prevalence and parasite density were comparable between the different agroecosystems. The overall prevalence of anaemia was 64.2%. The prevalence of haematological manifestations such as moderate (48.0%) and severe (8.0%) anaemia, leucopenia (26.9%) and microcytosis (30.8%) was significantly higher among Plasmodium-STH co-infected participants. Soil samples from plantations showed the highest prevalences of STH eggs compared to soil samples from areas around pit toilets and public water taps. Living in a tea plantation area (OR = 3.07), age (AOR = 1.49) and lack of access to potable water (OR = 2.25) were identified as risk factors for STH infections, while the age groups 15-25 years (OR = 2.928) and 26-35 years (OR = 2.832), and being female (OR = 2.671) were significant risk factors for anaemia., Conclusions: STHs, malaria and anaemia are still of public health concern in plantation communities. Co-infections negatively influence haematological parameters. The tea farming agroecosystem, age and lack of access to potable water were identified as significant risk factors for STH infections., Trial Registration: Not applicable.

Toxocara canis, Toxocara cati and Ascaris suum are worldwide-distributed zoonotic roundworms of dogs, cats and pigs, respectively. The epidemiology of these parasites in developed countries is largely unclear. Two countrywide cross-sectional serosurveys were therefore conducted in the Netherlands in 1995/1996 and 2006/2007 to investigate the prevalence, trends and risk factors for human Toxocara and Ascaris infections in the general population. The Netherlands is characterized by high pig production, freedom from stray dogs and virtual absence of autochthonous infections with the human-adapted roundworm Ascaris lumbricoides. Over the 10 years between the two serosurveys, Toxocara seroprevalence decreased significantly from 10.7 % (n = 1159) to 8.0 % (n = 3683), whereas Ascaris seroprevalence increased significantly from 30.4 % (n = 1159) to 41.6 % (n = 3675), possibly reflecting concomitant improvements in pet hygiene management and increased exposure to pig manure-contaminated soil. Increased anti-Toxocara IgGs were associated with increasing age, male gender, contact with soil, ownership of cats, cattle or pigs, hay fever, low education, high income and non-Western ethnic origin. Increased anti-Ascaris IgGs were associated with increasing age, owning pigs, low education, childhood geophagia and non-Dutch ethnic origin. Besides identifying specific groups at highest risk of Toxocara and Ascaris infections, our results suggest that these infections mainly occur through environmental, rather than foodborne, routes, with direct contact with soil or cat and pig ownership being potentially modifiable exposures.

Soil-transmitted helminth (STH) infections and micronutrient deficiencies are closely related and often coexist among low-income populations. We studied the association between infections with specific STH species and micronutrient status in rural Vietnamese schoolchildren. Children (N = 510) aged 6-9 years were recruited from two primary schools. STH infections were determined in stool samples. Hemoglobin, ferritin, retinol, and zinc were measured in blood samples, as well as C-reactive protein to control for inflammation. Iodine excretion was measured in urine. Associations of single and multiple infections with Ascaris lumbricoides, Trichuris trichiura, and hookworm with micronutrient status (hemoglobin, plasma ferritin, retinol, zinc, and urinary iodine) were estimated by multiple regression analysis. Ascaris infections showed a specific and intensity-dependent negative association with vitamin A. Trichuris and hookworm infections were associated with lower hemoglobin concentration, but not with plasma ferritin. Trichuris-infected children had zinc deficiency less often than uninfected children. In conclusion, our study shows species-specific associations between STH infections and micronutrient status in children. The different life cycles of STH species might have specific effects on the absorption or loss of specific micronutrients. Tailor-made combinations of deworming and nutritional interventions may be needed to improve child health and nutrition., (© The American Society of Tropical Medicine and Hygiene.)

Background: The prevalence of helminth infection, which is known to affect nutritional status of the host, varies with age. The complex interplay between ages, nutrient requirements, and infection necessitated the need to recommend micronutrient supplementation during helminth infection among different age groups., Objective: The aim of this study was to determine the pattern of alteration in selected micronutrients in pregnant women and preschool- and school-aged children with helminth infection., Methods: We screened 245 pregnant women and 349 children for helminth infection. Of these, 17 (6.9%) pregnant women and 102 (29.2%) children (42 preschool- and 60 school-aged) had helminth infection. Only Ascaris lumbricoides was found in pregnant women, whereas the children had A lumbricoides, hookworm, Fasciola hepatica, and Trichuris trichiura infections. The helminth-infected (HI) pregnant women, preschool-aged children, and school-aged children were matched with helminth-negative (HN) pregnant women (n = 21), preschool-aged children (n = 42), and school-aged children (n = 50) who served as controls. Venous blood samples were obtained and analyzed for iron (Fe), zinc (Zn), selenium (Se), and vitamins A and C. Statistical analysis was done using Student's t test, and P < 0.05 was considered statistically significant., Findings: Serum levels of Fe, Zn, and Se were significantly lower in HI pregnant women than HN pregnant women. In preschool-aged children, serum levels of Fe, Zn, and vitamin A were significantly lower in the HI than in the HN group. Similarly, serum levels of Zn and vitamin A were significantly lower in HI school-aged children than in the HN group. However, serum levels of Se were significantly higher in HI children (both age groups) than in the corresponding HN group., Conclusion: Helminth infection alters different types of micronutrients in children and pregnant women. Results from the present study therefore suggest monitoring Fe, Zn, or vitamin A supplementation with an anti-helminthic regimen., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

A humoral immune response following helminth infection in pigs is well documented. However, it has been difficult to confirm the existence of antibody mediated resistance against the large roundworm, Ascaris suum, and whipworm, Trichuris suis, in experimental settings by correlating worm burdens or egg excretion with specific antibody levels. We set out to investigate the association between worm load and T. suis and A. suum specific serum antibody levels (IgG1, IgG2 and IgA) against excretory-secretory products of adults and third stage larvae, respectively, measured at 0, 7 and 14 weeks p.i. in a trickle-infected F1-resource-population of crossbred pigs (n=195). Furthermore, we wanted to determine the heritability of these antibody isotypes during the course of infection. Most pigs remained infected with A. suum throughout the experiment while they expelled T. suis between 7 and 14 weeks post infection (p.i.). Parasite specific IgG1 and IgA were significantly (P<0.001) elevated after 7 and 14 weeks of infection, whereas parasite specific IgG2 levels only changed slightly at 14 weeks p.i.. However, the observed association between specific antibody isotype levels and faecal egg counts and macroscopic worm load was weak. The relative heritabilities of the different parasite specific isotypes were assessed and resulted in significant heritability estimates for parasite specific IgG1 and IgA. The highest heritabilities were found for A. suum specific IgG1 (h(2)=0.41 and 0.46 at 7 and 14 weeks p.i., respectively). Thus, the present study demonstrates that host genetic factors influence the IgG1 and IgA antibody isotype responses specific to two of the most common gastrointestinal nematodes of swine whereas specific antibody levels were poorly associated with egg excretion and the presence of macroscopic worms., (Copyright © 2015. Published by Elsevier B.V.)

Objective: To assess the prevalence of malaria helminth co-infections and their contribution for aneamia in febrile patients attending Azzezo health center, Gondar, Northwest Ethiopia., Methods: A cross section study was conducted among febrile patients attending Azezo health center from February-March 30, 2011. Convenient sampling technique was used to select 384 individuals. Both capillary blood and stool were collected. Giemsa stained thick and thin blood film were prepared for identification of Plasmodium species and stool sample was examined by direct wet mount and formalin-ether concentration technique for detection of intestinal helminthes parasites. Haemoglobin concentration was determined using a portable haemoglobin spectrophotometer, Hemocue Hb 201 analyzer., Results: Out of 384 febrile patients examined for malaria parasites, 44 (11.5%) individuals were positive for malaria parasites, of which Plasmodium vivax accounted for 75.0% (33), Plasmodium falciparum for 20.5% (9) infectious, whereas two person (4.5%) had mixed species infection. Prevalence of malaria was higher in males (28) when compared with prevalence in females (16). More than half (207, 53.9%) of study participants had one or more infection. Prevalence was slightly higher in females (109, 52.7%) than in males (98, 47.3%). About helminths, Ascaris lumbricoides was the predominant isolate (62.1%) followed by hookworms (18.4%). Only 22 participants were co-infected with malaria parasite and helminths and co-infection with Ascaris lumbricoides was predominant (45.0%). The prevalence of anemia was 10.9% and co-infection with Plasmodium and helminth parasites was significantly associated with (P< 0.000 1) higher anemia prevalence compared to individuals without any infection., Conclusions: Prevalence of malaria and soil transmitted helminths is high and the disease is still major health problem in the study area. Hence, simultaneous combat against the two parasitic infections is very crucial to improve health of the affected communities in economically developing countries., (Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.)

Despite the common occurrence of ascariasis in southwestern Uganda, helminth control in the region has been limited. To gain further insights into the genetic diversity of Ascaris in this area, a parasitological survey in mothers (n=41) and children (n=74) living in two villages, Habutobere and Musezero, was carried out. Adult Ascaris worms were collected from infected individuals by chemo-expulsion using pyrantel pamoate treatment. Genetic diversity within these worms was assessed by inspection of DNA sequence variation in a mitochondrial marker and length polymorphism at microsatellite loci. Overall prevalence of ascariasis was 42.5% in mothers and 30.4% in their children and a total of 98 worms was examined from 18 hosts. Sequence analysis of a portion of the mitochondrial cytochrome c oxidase subunit 1 gene revealed 19 different haplotypes, 13 of which had not been previously encountered. Microsatellite analysis using eight loci provided evidence for high gene flow between worm populations from the two villages but comparing these worms with others obtained in a prior study on Unguja, Zanzibar, confirmed little genetic exchange and mixing of worm populations between the two areas. By adding to our understanding of the genetic diversity of Ascaris in Africa, this study provides useful information for monitoring changes in parasite population structure in the face of ongoing and future control., (Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.)

Ascariasis is the most common soil-transmitted helminth infection in the world. The objective of this study was to analyze the clinical symptoms and selected hematological indices of ascariasis in hospitalized children from the northeastern region of Poland. Patients in the Pediatric Ward hospitalized in the Regional Hospital in Dabrowa Białostocka in the period of 2005-2007 were included in this retrospective study. The intestinal stage of ascariasis was diagnosed on the basis of positive coprological survey performed using the decantation technique. A total of 938 patients were included in the study, 1801 stool samples were evaluated, and A. lumbricoides-positive tests were obtained from 252 children. Ascaris-positive young children (< or = 3 yrs) accounted for 3.0% of all hospitalized children, Ascaris-positive preschool-aged children (4-7 yrs) accounted for 8.1% and school-aged children (8-18 yrs) for 15.8%. Seasonal patterns were observed in the prevalence of A. lumbricoides (maximum in August-December). There was no relationship between BMI z-score, hemoglobin levels and prevalence of infection with Ascaris lumbricoides. Significant predictors of intestinal stage ascariasis in a multivariate logistic regression model were: abdominal pain as a reason for hospital admission (OR-2.19; 95% CI 1.62-2.95; p < 0.001) and age from 4 to 7 years (OR-2.0; 95% CI 1.41-2.80; p < 0.001). The prevalence rate of ascariasis was not higher in the group of patients with atopic diseases (bronchial asthma, allergic rhinitis, atopic dermatitis) and co-existing ascariasis did not affect the eosinophil counts in the peripheral blood. Ascariasis is still a current pediatric clinical problem characterized by non-specific clinical manifestations, which should be taken into consideration in the differential diagnosis of children's diseases.

Objectives: Caras-Severin County presented the highest incidence of human trichinellosis (108.5 cases per 100,000 inhabitants) throughout Romania in 1993. This study aimed at providing an overview of the epidemiological and clinical characteristics of persons from this county hospitalized with nematodal infections between 1996 and 2008., Patients and Methods: Data were collected from the medical records of 269 patients admitted to two infectious diseases hospitals and found to have nematode helminthic infections., Results: Of the study group, 250 patients (92.9%) presented with trichinellosis, 10 (3.7%) with ascariasis, 7 (2.6%) with trichuriasis, and 2 (0.8%) with ascariasis and trichuriasis coinfections. Geohelminthic infections prevailed in children (68.4%). Giardiasis, a protozoan parasitic disease, was also found in 21 patients (7.8%)., Conclusions: Although trichinellosis cases decreased in this county, public health authorities must remain aware because new outbreaks may occur at any time as it happened in the neighboring counties. Regarding geohelminthiasis, parents must be aware of the potential risk of acquiring these infections and the major complications that may follow.

Soil-transmitted helminths (STHs) remain a major threat to the health of children throughout the world, mostly in developing nations. The aim of the present study was to determine any relationship between STHs and hemoglobin status in school children of Kashmir Valley (India). Stool and blood samples were collected from 382 male and female school children in the age group of 5-15 yr from all 6 school districts of the Kashmir Valley. Finger-prick blood samples were used to collect the hemoglobin, which was then measured on-site by Sahli's acid hematin method; stool samples were processed using both simple smear and zinc sulphate concentration methods. Of the 382 children surveyed, 299 (78.27%) were infected with Ascaris lumbricoides, Trichuris trichiura, or both. Children infected by STHs were found to have lower mean values of hemoglobin than uninfected children. The present study reveals that STHs are abundant among school children of Kashmir Valley, creating a negative effect on the hemoglobin values and indicating the necessity of implementing control measures.

Vitamin A deficiency and malnutrition are still considered public health problems in rural areas of developing countries, including Malaysia. A cross-sectional exploration study was carried out on 281 Orang Asli (Aborigine) children aged between 2 and 15 years in Selangor, Malaysia. The overall prevalence of low serum retinol (<70 micromol/l) and hypoalbuminaemia (<35 g/l) were 25.2 and 7.8%, respectively. Univariate analysis showed that severe ascariasis, significant stunting and giardiasis were significantly associated with low concentration of serum retinol. As well as intestinal parasitic infections, low socio-economic status was a significant predictor of hypoalbuminaemia. Logistic regression analysis identified severe ascariasis and significant stunting as predictors of low serum retinol, while mixed intestinal parasitic infection and low household income were predictors of hypoalbuminaemia. In conclusion, control measures for intestinal parasitic infections should be included as one of the strategies for the prevention and control of malnutrition and vitamin A deficiency in this population.

The aim of this paper was to investigate the role of porcine basophils in protective immunity. Experimental pigs were infected with 10(3) Ascaris suum eggs daily for 21 days. Control pigs were maintained helminth-free. Circulating porcine basophils were isolated from the anticoagulated whole blood of A. suum-infected and noninfected pigs by dextran (4.5%) sedimentation of erythrocytes or by the centrifugation of dextran-isolated leukocytes through discontinuous Percoll gradients. Results showed that 2.2% of the isolated leukocytes, stained with May-Grunwald Giemsa, were basophils. Each basophil from infected pigs contained 1.30 x 10(-2) to 1.20 x 10(-1) pg of histamine. Peripheral blood basophils (PBBs) from infected swine released 49% specific histamine when induced with A. suum-derived antigen (L3L4ES), 55% with anti-immunoglobulin G, and 62% with calcium ionophore A23l87. During A. suum infection, the number of isolated basophils and histamine levels peaked at 14 to 21 days postinfection and then showed a significant decrease. Percent-specific histamine released from PBBs by infected swine was significantly greater than that released by control pigs. The L3L4ES antigen and secretagogues effectively induced specific/nonspecific histamine release from PBBs and should facilitate future investigations of porcine basophils.

The effect of iron fortification is generally assumed to be less than iron supplementation; however, the magnitude of difference in effects is not known. The present study aims to compare the efficacy of these two strategies on anaemia and iron status. After screening on low Hb, 425 anaemic children in six primary schools in Tam Nong district of Phu Tho province were included in a randomized, placebo-controlled trial comparing two groups receiving iron fortified instant noodles or iron supplementation for 6 months and a control group, with children in all groups having been dewormed. Blood samples were collected before and after intervention for haemoglobin, serum ferritin (SF), serum transferrin receptor (TfR), C-reactive protein (CRP), and haemoglobinopathies analysis. Regression analysis was used to assess the effect of iron fortification and iron supplementation on haemoglobin concentration, SF, TfR, body iron, and anaemic status as outcome variables. The improvement of haemoglobin, SF, and body iron level in the group receiving iron fortification was 42% (2.6 g/L versus 6.2 g/L), 20% (23.5 microg/L versus 117.3 microg/L), and 31.3% (1.4 mg/kg versus 4.4 mg/kg) of that in the iron supplementation group. The prevalence of anaemia dropped to 15.1% in the control group, with an additional reduction of anaemia of 8.5% in the iron supplementation group. The additional reduction due to iron fortification was 5.4%, which amounts to well over 50% of the impact of supplementation. In conclusion, the efficacy of iron fortification based on reduction of prevalence of anaemia, and on the change in haemoglobin level, is about half of the maximum impact of supplementation in case of optimal compliance. Thus, in a population of anaemic children with mild iron deficiency, iron fortification should be the preferred strategy to combat anaemia.

Background: There is increasing evidence that the farming environment has a protective effect as regards allergic diseases. Exposure to animal parasites, particularly helminth infections, is common in the farming environment. However, the role of helminths in this environment is not well determined to date., Methods: This analysis focuses on 613 children 6-13 years of age from rural areas of Austria, Germany and Switzerland, who took part in the Allergy and Endotoxin (ALEX) study. Allergic diseases and farming characteristics were assessed by a standardized questionnaire and as a crude measure of possible exposure to helminths, IgG antibodies to Ascaris lumbricoides were measured., Results: Exposure to nematodes, as determined by the levels of antibody to A. lumbricoides, was more frequent among farmers' children than non-farmers' children (39.8%vs 31.1%, P = 0.03). This positive serology was found to be significantly associated with high total IgE levels [odds ratio (OR) = 3.05, 95% confidence interval (CI) = 1.81-5.12] and eosinophilia (OR = 2.84, 95% CI = 1.66-4.84). However, no association between anti-nematode serology and the prevalences of asthma, wheeze, hay fever or atopy was found. A weak association for atopy was observed after adjustment for total IgE., Conclusion: Immunoglobulin G antibodies to A. lumbricoides, as a crude measure of possible exposure to helminths, did not indicate any protective effect against allergic diseases in this population. Although farmers' children had increased antibody levels reactive to helminth parasites indicating exposure, this did not explain the protective effect of farming against atopic diseases.

Zinc deficiency is a public health issue in Bangladesh. The objectives were to identify predictors of serum zinc concentration and to assess the prevalence of low serum zinc, in both the whole population, after correcting for the effect of serum C-reactive protein (CRP) (using multiple categories), and the healthy subgroup. A cross-sectional study was conducted among 579 apparently healthy 3-7 y old children from a Dhaka slum, Bangladesh. Using multiple linear regression, the effects of age, gender, serum CRP and alpha 1-antichymotrypsin, reported morbidity, Ascaris lumbricoides and Trichuris trichiura infections, parental education as well as stunting, underweight, and wasting on serum zinc were estimated. Serum zinc (mean +/- SD) was 9.7 +/- 1.1 micromol/L. Elevated serum CRP levels, T. trichiura infection, and stunting were negative predictors of serum zinc, whereas maternal education was a positive predictor. Compared with serum CRP <1 mg/L, CRP levels of 2 to <5, 5 to <10 and > or =10 mg/L were associated with 0.33, 0.73, and 0.89 micromol/L lower serum zinc, respectively. The prevalence of low serum zinc (<9.9 micromol/L) fell from 59.3 to 49.7% in the whole population, after correcting for the effect of CRP and was 50.0% in the healthy subgroup (CRP <2 mg/L). The prevalence of low serum zinc was high but overestimated due to the effect of the acute phase response. Interventions to address low serum zinc in Bangladesh are warranted. Controlling T. trichiura infection and improving maternal education may be important interventions. The use of multiple categories of acute phase proteins and cut-off values that indicate elevated levels warrant further research.

In order to increase the intestinal absorption of iron whilst simultaneously minimising the side-effects and thus increasing compliance, once- or twice-weekly, instead of daily, iron supplementation has been widely recommended. In a randomized, placebo-controlled, double-blind study in western Kenya, a tablet of ferrous dextran (containing 60 mg elemental iron) or an identical-looking placebo tablet was provided twice-weekly for 12 months to each child or adult investigated. At baseline each subject had a moderately low blood concentration of haemoglobin (Hb). Initial Hb and serum ferritin (SF) concentrations were determined and each subject was tested for malarial and helminth infection and treated, if necessary, with the appropriate anthelminthic drug(s). Overall, 200 children (aged 4-15 years) and 129 adults (aged 16-63 years) completed the 12-month study. At baseline, 47.5% of the children and 58.1% of the adults were anaemic, hookworm (detected in 60.0% of the children and 69.9% of the adults) was the most common helminth infection, and malaria was endemic. The results of bivariate analyses indicated that twice-weekly iron supplementation had no significant effect on blood Hb or SF concentrations, either in the children or the adults investigated. The results were confirmed in multiple linear-regression analyses, which revealed that the predictors of the final Hb concentration in the children investigated were age and infection, after enrollment, with Ascaris lumbricoides. Gender and the serum concentration of alpha-1-antichymotrypsin (ACT) at final follow-up were predictors of the final SF concentration in the children. In adults, the predictors of the final Hb concentration were gender and HIV infection, and the predictors of the final SF concentration were age and the serum concentration of ACT at the final follow-up. Twice-weekly iron supplementation did not increase Hb or iron stores in children or adults. Since compliance appeared to be high, this lack of effect may be the result of an inadequate dose of iron or of subjects who have deficiencies in micronutrients other than iron.

Cytokine-mediated regulation of chronic intestinal helminth infections is well documented. The present study reports the serum cytokine responses in 38 ascariasis (stool samples positive for Ascaris lumbricoides ova) and toxocariasis (seropositive) patients, 8 ascariasis-positive and toxocariasis-seronegative patients, 22 endemic, normal, healthy subjects residing in areas hyperendemic for ascariasis and 16 normal healthy subjects residing in a low-endemic area in India. The results indicated T-helper type-2-type cytokine responses in ascariasis and toxocariasis (seropositive) and ascariasis-positive and toxocariasis-seronegative patients. The important observation was that both patients and healthy individuals in ascariasis-hyperendemic areas had significantly higher interleukin-5 (IL-5) responses than non-endemic control subjects. The altered immune responses of patients in areas hyperendemic of ascariasis may have further implications. Earlier reports suggest that the geohelminth parasites in endemic areas may modulate the immune response to oral vaccines. A critical role for IL-5 in the immune response against challenge infection consistent with the association of type-2 cytokines with vaccine-mediated protection has been reported. Furthermore, co-infection by pathogens that elicit opposing immune responses, particularly helminths vs HIV and tuberculosis, could influence the infection dynamics, progression and immunoprophylaxis of the diseases they cause. Further studies are warranted to ascertain these findings.

In recent years there have been major socio-economic changes within Afghanistan such that the present public health burden of soil-transmitted helminths (STH), especially that within school-aged children, remains to be determined. A baseline parasitological survey was therefore carried out in four defined areas of Afghanistan to better assess the distribution, prevalence and intensity of STH infections prior to a nationwide de-worming campaign beginning within World Food Programme assisted schools. A cross-sectional examination of 1001 children aged between 8 and 15 years old revealed that approximately half (47.2%) were infected with at least one STH. Infections with Ascaris lumbricoides were most widespread (40.9%) and elevated prevalences were detected in urban environments; for example, schoolchildren in Kabul were more likely to be infected (OR=2.2, 95% CI 1.6-3.0) than elsewhere and these infections were often of higher intensity (OR=7.6, 95% CI 4.9-11.8). Trichuris trichiura (9.9%) and hookworms (0.7%), previously unknown from Afghanistan, were encountered. The blood haemoglobin concentration of surveyed children was also assessed: 4% resulted to be anaemic (Hb<11 g dl(-1)), and 0.4% to be severely anaemic (Hb<7 g dl(-1)).

This study investigated associations between pre-treatment cytokine expression and infection patterns, before and after de-worming, in humans exposed to two gastrointestinal nematode species. Quantitative measures of Ascaris lumbricoides and Trichuris trichiura infection (based on faecal egg counts) were estimated immediately before and 8-9 months after treatment in a Cameroonian population. Whole blood cytokine responses to parasite-derived antigens were assayed immediately pre-treatment. An overall measure of the tendency towards species-specific infection (increasing with A. lumbricoides faecal egg counts and decreasing with T. trichiura faecal egg counts) was significantly positively related to IL-10 levels in older (14-57 year) hosts. There was a significant negative influence of IL-5 on reinfection probability in T. trichiura but not A. lumbricoides. This effect coincided with reduced reinfection success in T. trichiura compared to A. lumbricoides. T(H)2 cytokine expression by younger hosts (4-13 year) was negatively associated with contemporary A. lumbricoides faecal egg counts before treatment. Following treatment, the pre-treatment T(H)2 cytokine expression data for younger hosts (now reflecting responsiveness 8-9 months in the past) were negatively associated with T. trichiura faecal egg counts. Taken together, these observations suggest a successional interaction between T(H)2-driven immune responses and species infection over time. However, any differential effects of the measured immune responses on species-specific recruitment, maturation and mortality were superimposed upon (and outweighed by) the effects of other factors favouring coinfection.

The immunodetection of local Ascaris suum antigens and local and systemic antibodies were analysed in pigs reinfected with eggs or immunized with the 14, 42 and 97 kilodalton (kDa) fractions from A. suum. Twenty-one Iberian pigs were divided in 7 groups of 3 pigs. Groups 1 and 2 were uninfected and challenge control groups, respectively. Groups 3 and 4 were infected weekly with increasing doses of A. suum eggs and Group 4 was additionally treated with pyrantel pamoate. Groups 5, 6 and 7 were immunised with the 14, 42 or 97 kDa fractions from adult worms, respectively. Groups 2-7 were challenged with 10,000 infective eggs. Animals of Groups 3 and 4 showed a pulmonary granulomatous reaction with moderate number of eosinophils and leukocytes, while Groups 5-7 presented higher number of cells, especially in animals immunized with the 42 kDa fraction. These immunized groups presented abundant deposition of Ascaris body fluid (BF) and body wall (BW) antigens as well as the 14 and 42 kDa fractions in the pulmonary and intestinal tissues, while lower deposition of antigens was observed in animals of Groups 3 and 4. The immunized pigs of Groups 5 and 6 showed the highest systemic IgG titres in serum and these antibodies were negatively correlated with the number of larvae recovered in the lungs, suggesting that the IgG response may have a protective function against the ascariosis. The highest concentrations of IgA-bearing cells were observed in animals of Groups 3 and 4 compared to the immunised pigs (Groups 5-7), suggesting that local IgA production may be involved in the protection against migrating larvae. The main localisations of IgA-bearing cells were the bronchial and peribronchial areas of lungs and the lamina propia of duodenum. Low numbers of local IgG-bearing cells were observed in all animals and no IgM-bearing cells were detected in the local tissues.

Despite the large-scale application of ivermectin for the treatment of human onchocerciasis, this filarial disease has remained a public health hazard, requiring rapid and sensitive diagnostic methods for more efficient management. Several serological methods based on homologous native or recombinant diagnostic antigens have been developed. However, these antigens have remained scarce in the endemic areas. We report herein the preparation and evaluation of an Onchocerca ochengi total worm extract together with its low molecular weight (< 31 kDa) and 14.4 kDa antigens for the diagnosis of human onchocerciasis. The 14.4 kDa antigen and the low molecular weight antigen fraction were identified by Western blot experiments. The antigens were employed for the detection of IgG4 in sera of 43 onchocerciasis patients, 35 normal Africans, 15 schistosomiasis patients, 11 ascariasis patients, 9 loaisis patients and 3 healthy Europeans. The diagnostic specificity values were 94.5, 87.5 and 100%, while the sensitivities were 90.7, 80 and 76.6% using the worm extract, low molecular weight antigen fraction and the 14.4 kDa antigen, respectively. We conclude that total worm extracts of O. ochengi can conveniently replace recombinant antigen cocktails in poor settings that do not have access to the latter.

Serological analyses of sera from patients with a typical picture of filarial tropical pulmonary eosinophilia (TPE) and sera from patients from a region non-endemic for filariasis harbouring intestinal helminths, as Ascaris lumbricoides and Strongyloids stercoralis, revealed equally high titers of IgG4, usually considered diagnostic for filariasis. Ultrathin sections of adult worms of W. bancrofti embedded in the hydrophilic resin L.R. White were incubated with sera from patients with a typical picture of filarial tropical pulmonary eosinophilia (TPE) and sera from patients of a region that was non-endemic for filarial TPE but endemic for intestinal helminths. Both groups had a similar pattern of labelling, except that the labelling intensity was higher with the sera of patients with filarial TPE. The present study indicates relevant epitopes recognised by sera from TPE-patients and also individuals with intestinal helminths in all tissues of adult and intra-uterine microfilaria of W. bancrofti, instead of being localised in a specific nematode region. These findings suggest that people from areas not endemic for filariasis, but who harbour intestinal helminths, also share antifilarial antibodies in their serum that recognise antigens of adult worms and intrauterine microfilaria of W. bancrofti.

Human toxocariasis caused by Toxocara canis is common in both developing and developed countries and leads to visceral larva migrans with high morbidity and mortality. Ascariasis caused by Ascaris lumbricoides, too has global distribution and in India, high prevalence rate has been reported in Kashmir (J & K State). Both nematode parasites, Toxocara canis and A. lumbricoides require similar biological and environmental conditions for the development of eggs in soil. Therefore, the present study was attempted to detect the antibody response to T. Canis excretory-secretory (ES) antigen by enzyme linked immunosorbent assay in patients attending Sher-I-Kashmir Institute of Medical Sciences, Soura, Srinagar, Kashmir to assess the magnitude of human toxocariasis in Kashmir, the highly endemic area of ascariasis. Interestingly, it was observed that 38 (82.60%) out of 46 patients harbouring Ascaris Iumbricoides had positive antibody response to T. Canis ES antigen while none of the 15 normal healthy subjects from the same endemic zone, 25 from low endemic zone Chandigarh and 15 from other parasitic infections (hookworm, hydatidosis, cysticercosis) indicated detectable positive response. Majority of the ascariasis positive patients studied were in the age group of 21-40 years. However, one ascariasis patient studied in the age group of 1-10 years (4 years old) had also positive antibody response to T. Canis antigen. This study is the first report of human toxocariasis in Kashmir, India, an endemic zone for ascariasis and emphasizes the need for detailed epidemiological study for the ultimate prevention and control of this disease

Soluble adhesion molecules namely soluble intercellular adhesion molecule-1 (sICAM-1) and soluble E-selectin (sELAM-1) were assayed in hydatid patients with or without complications. It was found that sICAM-1 was significantly increased in patients with hydatid cysts as compared to the control group. In lymphoedemic filariasis cases both sICAM-1 and sELAM-1 showed highly significant increase more than the control group. However, non of both soluble adhesion molecules were significantly elevated in patients with ascariasis, hymenolepiasis, heterophyiasis and strongyloidiasis as compared to controls. The results indicated that SICAM-1 & S ELAM-1 are useful markers for hydatidosis and filariasis, but not for ascariasis, hymenolepiasis, heterophyiasis and strongyloidiasis

Antigens were identified from the third-stage larvae (L3) and lung-stage larvae of Ascaris suum by two-dimensional immunoblot method with antisera obtained from pigs that received chemically abbreviated Ascaris suum larval infections. Forty-seven and 13 spots were recognized as antigens from the L3 and lung-stage larvae, respectively. Their apparent molecular weight ranged from 20 to 101 kDa and their isoelectric point from 3.6 to 8.0. The present study provides a framework for further molecular cloning of those antigens and consequently leads to the development of recombinant peptide vaccines against A. suum.

WHO recommends that anthelmintic treatment be included in strategies to improve maternal nutrition in areas where hookworms are endemic and anaemia is prevalent. At present, few countries have adopted this recommendation, partly owing to the lack of data to support the adverse effects of hookworms on maternal health. A longitudinal study was conducted on 125 women in Sierra Leone (in 1995/96) to measure the impact of single-dose albendazole (400 mg) and daily iron-folate supplements (36 mg iron and 5 mg folate) on haemoglobin and serum ferritin concentration during pregnancy. Women who received both albendazole and iron-folate supplements experienced no significant change (P > 0.05) in the prevalence of anaemia and iron-deficiency anaemia between the first and third trimesters. These prevalence levels significantly increased (P < 0.05) in women who received either albendazole or iron-folate supplements or neither. After controlling for baseline haemoglobin concentration and season, the mean decline in haemoglobin concentration between the first and third trimester in women who received albendazole was 6.6 g/L less than in women who received the control (P = 0.0034). The corresponding value for iron-folate supplements was 13.7 g/L haemoglobin (P < 0.001). The effects of albendazole and iron-folate supplements were additive. These findings lend support to WHO's recommendation for anthelmintic treatment during pregnancy.

A randomized controlled trial in KwaZulu-Natal (South Africa) of 428 primary-school pupils (stratified into 6 groups by age, sex and intervention) measured the effect of different anthelmintic treatments and iron supplementation regimens provided twice at 6-monthly intervals for 1 year (1996/97). Half the pupils received iron supplementation (ferrous fumarate 200 mg weekly for 10 weeks). Pupils received 2 anthelmintic regimens, either (i) albendazole 400 mg plus praziquantel 40 mg/kg or (ii) albendazole 400 mg on 3 consecutive days plus praziquantel 40 mg/kg or (iii) placebo. Baseline prevalences of Ascaris 55.9%, Trichuris 83.6%, hookworm spp. 59.4%, were reduced after 12 months for single-dose albendazole treatment to Ascaris 17.4% (P < 0.005), Trichuris 61.5% (NS), hookworm spp. 0% (P < 0.005), and for triple-dose albendazole treatment to Ascaris 14.8% (P < 0.005), Trichuris 25.0% (P < 0.01), hookworm 0% (P < 0.005). Schistosoma haematobium 43.4% was reduced among treated groups to 8.3% (P < 0.005). There were no significant changes in the anthropometry of the different treatment groups at either 6 or 12 months post treatment. Twelve months after treatment there was a significant increase in haemoglobin levels (P = 0.02) among pupils receiving triple-dose albendazole, praziquantel and ferrous fumarate; pupils receiving no anthelmintic treatment showed a significant decrease as did pupils who received triple-dose albendazole and praziquantel but no iron. Regular 6-monthly anthelmintic treatment significantly reduced the prevalence of Ascaris, hookworm spp. and S. haematobium infections (P < 0.05). Triple-dose treatment for Trichuris was significantly more effective than a single dose of albendazole 400 mg (P = 0.002). In areas with schistosomiasis, hookworm infection and high prevalence of Trichuris infection, combination treatment with praziquantel, triple-dose albendazole, plus iron supplementation, is likely to improve pupils' health and haemoglobin levels.

A 24-week randomized double blind intervention trial was conducted on adult female tea pluckers from an estate in Bangladesh to investigate the impact of iron supplementation and anthelmintic treatment on changes in ferritin and haemoglobin levels as well as on prevalence and intensity of helminth infections. A total of 553 women were randomly assigned to 1 of 4 intervention groups: group 1 received iron supplementation on a weekly basis, group 2 received anthelmintic treatment at the beginning and half way through the trial, group 3 received both iron supplementation as group 1 and anthelmintic treatment as group 2, and group 4 was a control group and received placebos for both iron supplementation and anthelmintic treatment. Prevalence and intensity of helminth infections (egg counts/g stool) of Ascaris lumbricoides, Trichuris trichiura and hookworms significantly fell in the 2 groups receiving anthelmintic treatment and there were some reductions in the 2 groups not receiving anthelminthic treatment. Haemoglobin and haematocrit concentrations increased significantly in the iron supplemented groups with smaller increases in the anthelmintic only group. All women showed a decrease in serum ferritin levels post-trial with greater losses in the 2 dewormed groups. Significant negative associations were found between hookworm egg counts and ferritin levels and Trichuris trichiura egg counts and haemoglobin concentration.

To define the cytokine response to Ascaris lumbricoides infection, the cellular immune response to adult and larval-stage Ascaris antigens in young adults with moderate infection intensities (n=73) was compared with that of a group of uninfected control subjects (n=40). A. lumbricoides-infected subjects had significantly greater lymphoproliferative responses to adult and larval-stage antigens, compared with uninfected control subjects (P<.01). The frequencies of parasite antigen-stimulated peripheral blood mononuclear cell (PBMC)-expressing interleukin (IL)-4 and IL-5 were significantly greater in the infected group (P<.001), whereas the frequencies of IL-10- and interferon-gamma-expressing PBMC were similar in the 2 groups studied. The ratios of Th2 to Th1 cytokine frequencies were significantly elevated in the infected group, compared with those in uninfected subjects, as was IL-5 protein production by PBMC stimulated with adult (P<.05) and L3/L4 stage (P<.001) antigens. Analysis of these data indicates that A. lumbricoides infections in endemic regions are associated with a highly polarized type 2 cytokine response.

A randomized, placebo-controlled, double-blind trial was carried out in 1994-96 among 231 children and 181 adults in order to determine the effects of iron on reinfection rates and intensities of hookworm, Ascaris lumbricoides, Trichuris trichiura and Schistosoma mansoni. Adults given 60 mg elemental iron twice-weekly for 12 months had significantly lower reinfection rates of A. lumbricoides (16.7% vs 31.9%, P = 0.046), T. trichiura (6.9% vs 20.6%, P = 0.03) and S. mansoni (38.3% vs 61.8%, P = 0.008) compared to adults given placebo. In contrast, adults allocated to iron had a significantly higher reinfection rate of hookworm at the 4-month examination (11.1% vs 0%, P = 0.009), but the difference was not significant at 8- and 12-month follow-up examinations. Iron supplementation had no effect on reinfection intensities in adults. Surprisingly, iron supplementation had no effect on either reinfection rates or intensities in children. Multiple logistic regression analyses controlling for baseline infection status confirmed the effect in adults of iron on A. lumbricoides, T. trichiura and S. mansoni reinfection rates. The effect is suggested to be due to reduced risk behaviour, to improved immune function or to unfavourable host gut conditions caused by an increased oxidative stress. In each case, the lack of effect in children remains to be explained. In contrast, iron supplementation apparently was short-lived in favour of hookworm infection, an effect that needs further clarification. The findings suggest that iron supplementation has a role to play in helminth control programmes and that intraluminal factors may contribute to the regulation of some helminth infections.

The ABA-1 protein of Ascaris lumbricoides (of humans) and Ascaris suum (of pigs) is abundant in the pseudocoelomic fluid of the parasites and also appears to be released by the tissue-parasitic larvae and the adult stages. The genes encoding the polyprotein precursor of ABA-1 (aba-1) were found to be arranged similarly in the two taxa, comprising tandemly repeating units encoding a large polyprotein which is cleaved to yield polypeptides of approximately 15 kDa which fall into 2 distinct classes, types A and B. The polyprotein possibly comprises only 10 units. The aba-1 gene of A. lumbricoides is polymorphic, and the majority of substitutions observed occur in or near predicted loop regions in the encoded proteins. mRNA for ABA-1 is present in infective larvae within the egg, and in all parasitic stages, but was not detectable in unembryonated eggs. ABA-1 mRNA was confined to the gut of adult parasites, and not in body wall or reproductive tissues. Recombinant protein representing a single A-type unit for the A. lumbricoides aba-1 gene was produced and found to bind retinol (Vitamin A) and a range of fatty acids, including the pharmacologically active lipids lysophosphatidic acid, lysoplatelet activating factor, and there was also evidence of binding to leukotrienes. It failed to bind to any of the anthelmintics screened. Differential Scanning Calorimetry showed that the recombinant protein was highly stable, and unfolded in a single transition at 90.4 degrees C. Analysis of the transition indicated that the protein occurs as a dimer and that the dimer dissociates simultaneously with the unfolding of the monomer units.

A metalloaminopeptidase was identified in culture fluids collected during in vitro cultivation of adult Ascaris suum. The enzyme was purified by anion-exchange and size-exclusion HPLC. The M(r) of the enzyme was estimated at 293 kDa and consisted of subunits with M(r)s of 153 and 142kDa. The isoelectric point of the aminopeptidase was 4.7. The aminopeptidase displayed a substrate preference for terminal arginyl residues. Aminopeptidase activity was also present in muscle, female reproductive tissue, pharynx, pseudocoelomic fluid and intestine. Among the various tissues, aminopeptidase activity was highest in the intestines; the highest activity was found in culture fluids (three-fold higher than intestinal tissue). The aminopeptidase released by adult A. suum was enzymatically and biochemically identical to an aminopeptidase released during in vitro development of A. suum third- to fourth-stage larvae.

Background: Helminthic infections induce an IL-4-dependent polyclonal stimulation of IgE synthetization. It is still unclear, however, what role helminths play in allergic sensitization., Objective: We sought to determine the relationship between Ascaris-specific IgE and allergic sensitization in a nontropical country., Methods: In 2 consecutive cross-sectional surveys in 1992-1993 and 1995-1996, data from school entrants (age range, 5 to 7 years), third graders (age range, 8 to 10 years), and sixth graders (age range, 11 to 14 years) were collected. The 2 younger groups were reexamined in the second survey. Data for about 2300 children, including a cohort of 700 subjects, were analyzed. Ascaris IgE and total and specific IgE to inhalant allergens were measured, and skin prick tests were performed. Information about asthma and allergic rhinitis was collected by a questionnaire., Results: Children who were Ascaris-IgE seropositive (>0.35 IU/mL) in both surveys had 10-fold higher levels of total IgE (451 IU/mL vs 45 IU/mL, P < .001) and higher prevalence rates of allergen-specific IgE seropositivity (56.3% vs 26.6%, P < .001). They also had a higher prevalence of allergic rhinitis (12.6% vs 3.7%, P < .001) and asthma (5.7% vs 1.6%, P < .05). In subjects who were Ascaris-seronegative in the first survey but seropositive in the second survey, total and specific IgE increased markedly. Sensitization to Dermatophagoides pteronyssinus increased nearly 3-fold in this group. In contrast, in children who became Ascaris-seronegative, total and specific IgE decreased., Conclusions: Contact with low doses of helminthic antigen is associated with an increase of total and specific IgE production. Helminthic infections in East German children are not the cause for a low prevalence of allergies in the former East Germany.

The purpose of this study was observe the effects of soil-transmitted helminthiasis on the amounts of fatty acids in the serum. The subjects were 32 females with age ranging from 15 to 55 years old (22.6 +/- 12.0). The intensity of infection was light based on the criteria of the WHO Expert Committee. Seven fatty acids and serum cholesterol were determined, with the pentadecanoic acid (C15: 0) as internal standard. Serum fatty acid levels were correlated with age-group, dietary habit and body mass index. These factors were however not related with the levels of the serum fatty acids. But the amounts of palmitic acid and stearic acid in the infected group were markedly reduced as compared with the non-infected group.

The study was conducted to investigate the impact of intestinal helminthiasis and treatment on iron status and acute phase response (APR) among urban Indonesian primary school children, aged 8-11 years old. The prevalence of helminthiasis among these children was; Ascaris lumbricoides, 81.6%; Trichuris trichiura, 88.3%; and mixed infection of A. lumbricoides and T. trichiura, 70.0%. Of 120 children enrolled in the investigation, 59 received a single 400 mg dose of albendazole, and 61 received a placebo. Ten days following treatment, the prevalence of ascariasis and trichuriasis in the treatment group diminished to 0% and 27%, respectively, and in the placebo group to 63.9% and 68.9%. Plasma iron, hemoglobin, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell (WBC), interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor (TNF) concentrations were determined prior to the intervention and 10 days after. Plasma iron concentrations and WBC count rose in the treatment group (p=< or =0.05) when compared to baseline status. Increases in hemoglobin concentrations observed in the treatment group 10 days post-treatment were not statistically significant. CRP, IL-1, IL-6 and TNF were found to be within normal limits for both groups both before and after treatment. ESR increased significantly in both treatment and placebo groups when compared the rates measured before treatment. These findings show that treatment with albendazole is associated not only with a decreased worm burden in school children, but also a rise in plasma iron.

The excretory/secretory (ES) antigen(s) of Ascaris lumbricoides was fractionated into 10 fractions by gel chromatography on a Suparose 12 column in FPLC. Of these, the third fraction (Al III), showing binding activity with both IgE and IgG antibodies of A. lumbricoides infected patients' sera, was further resolved into 2 fractions (Al IIIa and Al IIIb) on passage through a Mono Q column. Al IIIb was found to be the most potent antigen due to its high binding affinity with IgE and IgG antibodies of Ascaris infected patients as evidenced by ELISA inhibition. Although a two to five-fold increase of serum IgE level was observed in all helminthic parasite infected patients studied compared to control subjects, Al IIIb specific IgE was detected in sera of all Ascaris infected and only 40% of hookworm infected patients. When Al IIIb was tested by ELISA with sera of control subjects, Ascaris, hookworm, Strongyloides and Trichuris infected patients, strong binding was observed with the IgE and also IgG of all the Ascaris infected patients; however, it cross-reacted with IgG in 50% of hookworm, 28.6% of Trichuris trichura and 22.2% of Strongyloides infected patients' sera; but with IgE only in 40% of hookworm infected patients' sera. Further study showed specific detection of IgG4 in all the serum samples of 65 Ascaris infected patients when Al IIIb antigen was allowed to react with different subclasses of IgG by ELISA, giving a sensitivity of 100%. Reactivities of Al IIIb with IgG1 and IgG3 were only 47.6 and 11.8% respectively and there was no reactivity with IgG2 subclass. No IgG4 reactivity against Al IIIb was observed in the sera of hookworm, Trichuris or Strongyloides infected patients and was similar to that observed with control subjects showing the 100% specificity of the test system. This study may therefore be regarded as a novel technique for serodiagnosis of ascariasis by measuring Ascaris specific IgG4.

In developing countries, both marginal vitamin A status and intestinal helminths are common among children. Indonesian children (n = 309, 0.6-6.6 y), known to be infected with Ascaris lumbricoides, were randomized into six different treatment groups (A-F). The treatments included 210 mumol vitamin A supplement and a dose of 400 mg albendazole (5-propylthio-1H-benzimidazol-2-yl carbamic acid methyl ester) administered orally either at the same health visit (Groups B and F) or at different contact times during a 1-mo period (groups A, C, D and E). Vitamin A status was assessed both before and 3-4 wk after the treatments by the modified relative dose response (MRDR) test. Vitamin A supplementation was most important in improving the vitamin A status (P < 0.0001) of these children, whereas treatment for ascariasis alone (P = 0.370) and the statistical interaction between treatment for ascariasis and vitamin A (P = 0.752) were not. Serum retinol concentrations marginally improved (P = 0.051) in two of the groups that received vitamin A and albendazole but not in the third group that received vitamin A only. The MRDR test proved a better discriminator of the effects of these treatments on vitamin A status than changes in serum retinol concentrations.

Ascaris lumbricoides is a worldwide intestinal infestation that may cause various complications. Biliary ascariasis, however, is a rare condition. We describe a child with biliary ascariasis. The patient's clinical symptoms were pain, vomiting and abdominal tenderness, and she was thought to have acute appendicitis. However, laboratory examination revealed high serum alkaline phosphatase and amylase levels, and ultrasonography and percutaneous cholangiography demonstrated biliary ascariasis. The patient was successfully treated with mebendazole and antispasmolytic drugs.

Helminthic infection can stimulate the interleukin-4 (IL-4)-dependent polyclonal synthesis of immunoglobulin E (IgE) in children endemically exposed to these parasites. As such children are also frequently at nutritional risk, in this study we considered the possible influence of malnutrition on serum IL-4 levels and the IgE response in helminthic infection. We evaluated 85 Ascaris-infected children living in an urban slum area of Caracas, Venezuela, and found that the serum levels of IL-4 and total IgE were significantly higher in malnourished children than in their well nourished counterparts. In contrast, the specific anti-Ascaris IgE antibody response was significantly lower in the malnourished group. After anthelmintic treatment of the children, the total serum IgE and IL-4 levels decreased significantly in the well nourished group, while the specific anti-Ascaris IgE antibody response increased. No significant change was detected, however, in the malnourished group. Our results suggested that malnutrition potentiates the polyclonal stimulation of IgE synthesis induced by helminths. As specific IgE antibody has been implicated in the resistance to helminthic infection, and the polyclonal stimulus diminishes this response, these factors may increase the susceptibility of malnourished children to such parasites.

Data regarding cross-reactions against Trichinella spiralis in humans are scarce and controversial. For this reason, we tested serum samples from patients with typhoid fever, brucellosis, toxoplasmosis, amoebiasis, cysticercosis, trichocephaliasis, ascariasis, and onchocerciasis against an antigenic extract of T. spiralis infective larvae in an enzyme-linked immunosorbent assay (ELISA) and an enzyme-linked immunoelectrotransfer blot (EITB) assay. All except one serum sample from the group of patients with onchocerciasis were negative in the ELISA; in the EITB assay, only faint bands were observed with the samples from patients with onchocerciasis and ascariasis and negative results were obtained with the samples from patients with other diseases. In conclusion, cross-reactions were found only in the groups of patients with other nematode infections and were of very low magnitude, most of them virtually negative.

The study reports on the association between serum retinol levels and prevalence of two intestinal helminths in a random sample of 592 children, 6-120 months of age. Faecal analyses were performed by Kato thick-smear technique, recording the presence of hookworm and Ascaris lumbricoides eggs. Serum retinol levels were determined by high pressure liquid chromatography (HPLC) and expressed in micrograms/dl. The presence of Ascaris lumbricoides eggs was associated with lower levels of serum retinol in children below 60 months of age (p < 0.05). The presence of hookworm eggs was not associated with lower levels of serum retinol in any age group. In addition children who received at least one course of mebendazole during the past 12 months recorded higher serum retinol levels than children who did not receive it (p < 0.01).

Twenty-six Ascaris-infected children and 21 control children (10 of whom had iron-deficiency anaemia) were subjected to haematological and oral iron absorption tests. The levels of oral iron absorption by the infected children and by the healthy controls were similar, whereas the level of absorption by the children with iron deficiency anaemia was relatively high. It therefore appears that Ascaris infection does not lead to iron malabsorption and iron deficiency anaemia in children.