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Chris C. Appleton - One of the best experts on this subject based on the ideXlab platform.

Philip J. Cooper - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Early-Life Geohelminth Infections on the Development of Wheezing at 5 Years of Age.
    American journal of respiratory and critical care medicine, 2018
    Co-Authors: Philip J. Cooper, Mauricio Lima Barreto, Laura C. Rodrigues, Carlos Sandoval, Martha E. Chico, Maritza Vaca, Leila Denise Alves Ferreira Amorim, Sofia Loor, David P. Strachan
    Abstract:

    Rationale: Exposures to Geohelminths during gestation or early childhood may reduce risk of wheezing illness/asthma and atopy during childhood in tropical regions.Objectives: To investigate the effect of maternal and early childhood Geohelminths on development of wheeze/asthma and atopy during the first 5 years of life.Methods: A cohort of 2,404 neonates was followed to 5 years of age in a rural district in coastal Ecuador. Data on wheeze were collected by questionnaire and atopy was measured by allergen skin prick test reactivity to 10 allergens at 5 years. Stool samples from mothers and children were examined for Geohelminths by microscopy.Measurements and Main Results: A total of 2,090 (86.9%) children were evaluated at 5 years. Geohelminths were observed in 45.5% of mothers and in 34.1% of children by 3 years. Wheeze and asthma were reported for 12.6% and 5.7% of children, respectively, whereas 14.0% had skin test reactivity at 5 years. Maternal Geohelminths were associated with an increased risk of w...

  • Effects of maternal Geohelminth infections on allergy in early childhood
    The Journal of allergy and clinical immunology, 2015
    Co-Authors: Philip J. Cooper, Mauricio Lima Barreto, Laura C. Rodrigues, Carlos Sandoval, Martha E. Chico, Maritza Vaca, Leila Denise Alves Ferreira Amorim, Agostino Strina, Ana Clara P Campos, David P. Strachan
    Abstract:

    BACKGROUND: Maternal Geohelminth infections during pregnancy may protect against allergy development in childhood. OBJECTIVE: We sought to investigate the effect of maternal Geohelminths on the development of eczema, wheeze, and atopy during the first 3 years of life. METHODS: A cohort of 2404 neonates was followed to 3 years of age in a rural district in coastal Ecuador. Data on wheeze and eczema were collected by means of questionnaire and physical examination at 13, 24, and 36 months of age. Atopy was measured based on skin prick test (SPT) reactivity to 9 allergens at 36 months. Maternal stool samples were examined for Geohelminths by microscopy. Data on potential confounders was collected after birth by questionnaire. RESULTS: Geohelminths were observed in 45.9% of mothers. Eczema and wheeze were reported for 17.7% and 25.9%, respectively, of 2069 (86.1%) children with complete follow-up to 3 years, and allergen SPT reactivity to any allergen was present in 17.2% and to house dust mite in 8.7%. Maternal Geohelminth infections were not significantly associated with eczema (adjusted odds ratio [OR], 1.26; 95% CI, 0.98-1.61), wheeze (adjusted OR, 1.02; 95% CI, 0.82-1.27), and SPT reactivity to any allergen (adjusted OR, 0.79; 95% CI, 0.61-1.01). In subgroup analyses maternal Geohelminths were associated with a significantly reduced risk of SPT reactivity to mite and other perennial allergens, and maternal ascariasis was associated with an increased risk of eczema and reduced risk of SPT reactivity to all allergens. CONCLUSION: Our data do not support a protective effect of maternal infections with Geohelminth parasites during pregnancy against the development of eczema and wheeze in early childhood, although there was evidence in subgroup analyses for a reduction in SPT reactivity to house dust mites and perennial allergens.

  • Impact of early life exposures to Geohelminth infections on the development of vaccine immunity, allergic sensitization, and allergic inflammatory diseases in children living in tropical Ecuador: the ECUAVIDA birth cohort study
    BMC infectious diseases, 2011
    Co-Authors: Philip J. Cooper, Mauricio Lima Barreto, Laura C. Rodrigues, Carlos Sandoval, Martha E. Chico, David P. Strachan, Irene Guadalupe, Edward Mitre, Thomas A.e. Platts-mills, George E. Griffin
    Abstract:

    Background Geohelminth infections are highly prevalent infectious diseases of childhood in many regions of the Tropics, and are associated with significant morbidity especially among pre-school and school-age children. There is growing concern that Geohelminth infections, particularly exposures occurring during early life in utero through maternal infections or during infancy, may affect vaccine immunogenicity in populations among whom these infections are endemic. Further, the low prevalence of allergic disease in the rural Tropics has been attributed to the immune modulatory effects of these infections and there is concern that widespread use of anthelmintic treatment in high-risk groups may be associated with an increase in the prevalence of allergic diseases. Because the most widely used vaccines are administered during the first year of life and the antecedents of allergic disease are considered to occur in early childhood, the present study has been designed to investigate the impact of early exposures to Geohelminths on the development of protective immunity to vaccines, allergic sensitization, and allergic disease.

  • Environmental determinants of total IgE among school children living in the rural Tropics: importance of Geohelminth infections and effect of anthelmintic treatment
    BMC immunology, 2008
    Co-Authors: Philip J. Cooper, Ana-lucia Moncayo, Martha E. Chico, Maritza Vaca, Neal Alexander, Susana Benitez, George E. Griffin
    Abstract:

    Background The environmental factors that determine the elevated levels of polyclonal IgE observed in populations living in the Tropics are poorly understood but may include Geohelminth infections. We investigated the association between Geohelminth infections and total IgE levels in school children in rural tropical Ecuador, and assessed the effect on IgE of repeated anthelmintic treatments over a period of 12 months. The study was nested within a cluster-randomized study that randomized 68 schools to receive either 400 mg of albendazole every 2 months over a year or no treatment. We studied random samples of children completing follow-up and representing four groups stratified by the presence of Geohelminth infection at baseline and treatment allocation. We measured levels of total IgE and anti-A. lumbricoides IgG (used as a measure of past and current Geohelminth infectious exposure) in blood samples collected at the start of the study and after 12 months.

  • Effect of albendazole treatments on the prevalence of atopy in children living in communities endemic for Geohelminth parasites: a cluster-randomised trial
    Lancet (London England), 2006
    Co-Authors: Philip J. Cooper, Ana-lucia Moncayo, Laura C. Rodrigues, Martha E. Chico, Maritza Vaca, David P. Strachan, Martin Bland, Evelin Mafla, Fernanda Sanchez, George E. Griffin
    Abstract:

    Summary Background Epidemiological studies have shown inverse associations between Geohelminth (intestinal helminth) infection and atopy, leading to the suggestion that Geohelminths might protect against allergy. Periodic deworming of school children with anthelmintics is a widely implemented intervention and has raised concerns that such programmes could increase allergy. We investigated the effect of repeated anthelmintic treatments with albendazole over 12 months on the prevalence of atopy and clinical indices of allergy. Methods We did a cluster-randomised controlled trial in schoolchildren from 68 rural schools. Children were randomly assigned by school to either albendazole (34 schools, 1164 children) every 2 months for 12 months, or to no intervention (34 schools, 1209 children). The intervention schools received a total of seven albendazole treatments. The primary outcome was atopy at 12 months (allergen skin-test reactivity), and analysis was by intention-to-treat for whole-school analyses and per protocol for children. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN61195515. Findings Data for analysis were available for all schools and from 67·4% (784 of 1164) and 70·1% (848 of 1209) of children in albendazole and no-treatment groups, respectively. Albendazole treatment caused large reductions in Geohelminth prevalence over the study period (adjusted odds ratio 0·13, 95% CI 0·09–0·19, p Interpretation We saw no increase in the prevalence of atopy or clinical allergy associated with albendazole treatment. Deworming programmes for schoolchildren are unlikely to be accompanied by an increase in allergy.

Jane Kvalsvig - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Geohelminth infections on neurological development
    Handbook of clinical neurology, 2013
    Co-Authors: Jane Kvalsvig, Marco Albonico
    Abstract:

    Abstract Published reviews vary on the question of whether Geohelminth infections affect cognitive development: some claim that the scarcity of evidence means that it is unlikely that they do; others present modest evidence for an effect; and others raise the possibility that the damage is considerable but largely unresearched. This chapter reviews the characteristics of the Geohelminths themselves and the pathways by which they could affect the development of children in endemic areas. It describes the progress made in the last decade in conceptualizing children's brains as complex adaptive systems, with the suggestion that infections at different stages in brain development might have different neurobehavioral consequences. An examination of research reports and review articles highlights the difficulties inherent in assessing the effects of Geohelminth infections: other serious obstacles to healthy development in the same population may mask the effects of the Geohelminths, and consequently the intensity and pathogenicity of the infection is probably an important issue. Selecting cognitive measures suitable for assessing development in very young children is no simple matter, and careful statistical analysis is required to tease out the primary and secondary factors at work. The insights gained from a broad range of relevant research reports have placed us in a better position to conduct more telling research into the effects of these widespread, but neglected, tropical diseases.

  • Patterns of Geohelminth infection, impact of albendazole treatment and re-infection after treatment in schoolchildren from rural KwaZulu-Natal/South-Africa
    BMC infectious diseases, 2004
    Co-Authors: Elmar Saathoff, Jane Kvalsvig, Annette Olsen, Chris C. Appleton
    Abstract:

    Background Geohelminth infection is a major health problem of children from rural areas of developing countries. In an attempt to reduce this burden, the Department of Health of the province of KwaZulu-Natal (KZN) established in 1998 a programme for helminth control that aimed at regularly treating primary school children for schistosomiasis and intestinal helminths. This article describes the baseline situation and the effect of treatment on Geohelminth infection in a rural part of the province.

  • patterns of Geohelminth infection impact of albendazole treatment and re infection after treatment in schoolchildren from rural kwazulu natal south africa
    BMC Infectious Diseases, 2004
    Co-Authors: Elmar Saathoff, Jane Kvalsvig, Annette Olsen, Chris C. Appleton
    Abstract:

    Background Geohelminth infection is a major health problem of children from rural areas of developing countries. In an attempt to reduce this burden, the Department of Health of the province of KwaZulu-Natal (KZN) established in 1998 a programme for helminth control that aimed at regularly treating primary school children for schistosomiasis and intestinal helminths. This article describes the baseline situation and the effect of treatment on Geohelminth infection in a rural part of the province.

Elmar Saathoff - One of the best experts on this subject based on the ideXlab platform.

George E. Griffin - One of the best experts on this subject based on the ideXlab platform.

  • Impact of early life exposures to Geohelminth infections on the development of vaccine immunity, allergic sensitization, and allergic inflammatory diseases in children living in tropical Ecuador: the ECUAVIDA birth cohort study
    BMC infectious diseases, 2011
    Co-Authors: Philip J. Cooper, Mauricio Lima Barreto, Laura C. Rodrigues, Carlos Sandoval, Martha E. Chico, David P. Strachan, Irene Guadalupe, Edward Mitre, Thomas A.e. Platts-mills, George E. Griffin
    Abstract:

    Background Geohelminth infections are highly prevalent infectious diseases of childhood in many regions of the Tropics, and are associated with significant morbidity especially among pre-school and school-age children. There is growing concern that Geohelminth infections, particularly exposures occurring during early life in utero through maternal infections or during infancy, may affect vaccine immunogenicity in populations among whom these infections are endemic. Further, the low prevalence of allergic disease in the rural Tropics has been attributed to the immune modulatory effects of these infections and there is concern that widespread use of anthelmintic treatment in high-risk groups may be associated with an increase in the prevalence of allergic diseases. Because the most widely used vaccines are administered during the first year of life and the antecedents of allergic disease are considered to occur in early childhood, the present study has been designed to investigate the impact of early exposures to Geohelminths on the development of protective immunity to vaccines, allergic sensitization, and allergic disease.

  • Environmental determinants of total IgE among school children living in the rural Tropics: importance of Geohelminth infections and effect of anthelmintic treatment
    BMC immunology, 2008
    Co-Authors: Philip J. Cooper, Ana-lucia Moncayo, Martha E. Chico, Maritza Vaca, Neal Alexander, Susana Benitez, George E. Griffin
    Abstract:

    Background The environmental factors that determine the elevated levels of polyclonal IgE observed in populations living in the Tropics are poorly understood but may include Geohelminth infections. We investigated the association between Geohelminth infections and total IgE levels in school children in rural tropical Ecuador, and assessed the effect on IgE of repeated anthelmintic treatments over a period of 12 months. The study was nested within a cluster-randomized study that randomized 68 schools to receive either 400 mg of albendazole every 2 months over a year or no treatment. We studied random samples of children completing follow-up and representing four groups stratified by the presence of Geohelminth infection at baseline and treatment allocation. We measured levels of total IgE and anti-A. lumbricoides IgG (used as a measure of past and current Geohelminth infectious exposure) in blood samples collected at the start of the study and after 12 months.

  • Effect of albendazole treatments on the prevalence of atopy in children living in communities endemic for Geohelminth parasites: a cluster-randomised trial
    Lancet (London England), 2006
    Co-Authors: Philip J. Cooper, Ana-lucia Moncayo, Laura C. Rodrigues, Martha E. Chico, Maritza Vaca, David P. Strachan, Martin Bland, Evelin Mafla, Fernanda Sanchez, George E. Griffin
    Abstract:

    Summary Background Epidemiological studies have shown inverse associations between Geohelminth (intestinal helminth) infection and atopy, leading to the suggestion that Geohelminths might protect against allergy. Periodic deworming of school children with anthelmintics is a widely implemented intervention and has raised concerns that such programmes could increase allergy. We investigated the effect of repeated anthelmintic treatments with albendazole over 12 months on the prevalence of atopy and clinical indices of allergy. Methods We did a cluster-randomised controlled trial in schoolchildren from 68 rural schools. Children were randomly assigned by school to either albendazole (34 schools, 1164 children) every 2 months for 12 months, or to no intervention (34 schools, 1209 children). The intervention schools received a total of seven albendazole treatments. The primary outcome was atopy at 12 months (allergen skin-test reactivity), and analysis was by intention-to-treat for whole-school analyses and per protocol for children. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN61195515. Findings Data for analysis were available for all schools and from 67·4% (784 of 1164) and 70·1% (848 of 1209) of children in albendazole and no-treatment groups, respectively. Albendazole treatment caused large reductions in Geohelminth prevalence over the study period (adjusted odds ratio 0·13, 95% CI 0·09–0·19, p Interpretation We saw no increase in the prevalence of atopy or clinical allergy associated with albendazole treatment. Deworming programmes for schoolchildren are unlikely to be accompanied by an increase in allergy.

  • reduced risk of atopy among school age children infected with Geohelminth parasites in a rural area of the tropics
    The Journal of Allergy and Clinical Immunology, 2003
    Co-Authors: Philip J. Cooper, Laura C. Rodrigues, Martha E. Chico, George E. Griffin, David P. Strachan, Marisol Ordonez, Thomas B Nutman
    Abstract:

    BACKGROUND: Childhood infections might protect against the expression of atopy. Geohelminths are among the most prevalent infections of childhood and might contribute to the low prevalence of allergic disease reported from rural areas of the tropics. OBJECTIVE: We sought to establish whether Geohelminth infections protect against atopy and to explore whether this protection is dependent on infection chronicity. METHODS: The risk of atopy (measured by means of allergen skin test reactivity) associated with active Geohelminth infections (measured by means of the presence of eggs in stool samples) or with chronic Geohelminth infections (measured by means of high levels [>/=3564 IU/mL] of total serum IgE or the presence of detectable anti-Ascaris lumbricoides IgG4 antibodies) was investigated in an analytic cross-sectional study conducted among school-age children attending rural schools in Pichincha Province in Ecuador. RESULTS: A total of 2865 children aged 5 to 19 years from 55 schools was examined. Active infection with any Geohelminth and infections with A lumbricoides or Ancylostoma duodenale were associated with significant protective effects against allergen skin test reactivity. Children with the highest levels of total IgE or with anti-A lumbricoides IgG4 antibodies were protected against skin test reactivity also, and the protective effects of high IgE or anti-A lumbricoides IgG4 and or active Geohelminth infections were statistically independent. CONCLUSION: Active infections with Geohelminth parasites and the presence of serologic markers of chronic infections (high levels of total serum IgE or anti-A lumbricoides IgG4) are independent protective factors against allergen skin test reactivity among school-age children living in an endemic region of the rural tropics.

  • Allergic symptoms, atopy, and Geohelminth infections in a rural area of Ecuador.
    American journal of respiratory and critical care medicine, 2003
    Co-Authors: Philip J. Cooper, Martha E. Chico, George E. Griffin, Martin Bland, Thomas B Nutman
    Abstract:

    Geohelminth infections may affect the expression of allergic disease. To investigate the relationship between Geohelminth infections, atopy, and symptoms of allergic disease, we studied 4433 schoolchildren from 71 schools in a rural tropical area in Ecuador. Information was collected on allergic symptoms, allergen skin test reactivity, and presence of Geohelminth infections. Allergic symptoms were of low prevalence (2.1% had recent wheeze), but prevalence of skin test reactivity was relatively high (18.2%). The presence of Geohelminth infections was protective against allergen skin test reactivity (odds ratio 0.62, 95% confidence interval 0.50-0.76, p < 0.001) and symptoms of exercise-induced wheeze (odds ratio 0.59, 95% confidence interval 0.40-0.87, p = 0.008) but not against other wheeze symptoms or symptoms of allergic rhinitis or atopic eczema. Infection intensity with Ascaris lumbricoides or Trichuris trichiura was associated with a reduction in the prevalence of allergen skin test reactivity but not with allergic symptoms. There was no evidence of interactions between Geohelminth infection and allergen skin test reactivity on the risks of allergic symptoms. The results suggest that Geohelminth infections do not explain the low prevalence of allergic symptoms in the study population.