Medicine

Permanent URI for this communityhttp://repository.kln.ac.lk/handle/123456789/12

This repository contains the published and unpublished research of the Faculty of Medicine by the staff members of the faculty

Browse

Filters

Settings

Has files: NoSubject: search.filters.subject.Helminthiasis

Search Results

Now showing 1 - 10 of 14
  • No Thumbnail Available
    Item
    Intestinal Nematodes: Ascariasis
    (Elsevier, 2020) Bundy, D.A.P.; de Silva, N.R.; Appleby, L.J.; Brooker, S.J.
    Ascariasis is the most prevalent human helminth infection, with an estimated 819 million infections worldwide. Transmission primarily occurs in warm, tropical climates that lack water and sanitation facilities and have poor hygiene. Worms inhabit the small intestine, and morbidity is related to worm burden. A small proportion of the infected population harbors the majority of worms, with intense infection most common in school-age children, and intensity and prevalence declining to a low level throughout adulthood. School-age children are therefore the targets for school-based community control efforts in large-scale treatment campaigns. Light infections can affect growth and development, whereas, due to the size of the worms, heavier worm burdens can result in intestinal obstruction, particularly in young children. Treatment with mebendazole or albendazole is efficacious, with cure rates of >90% commonly achieved.
  • No Thumbnail Available
    Item
    Intestinal nematodes that migrate through lungs (Ascariasis)
    (WB Saunders Company, 2000) de Silva, N.R.; Bundy, D.A.P.
  • No Thumbnail Available
    Item
    Effect of mass chemotherapy for filariasis control on soil-transmitted helminth infection in Western Province of Sri Lanka
    (The Royal Society of Tropical Medicine and Hygiene, 2007) Gunawardena, N.K.; Amarasekera, N.D.D.M.; Pathmeswaran, A.; de Silva, N.R.
    In July 2006, Sri Lanka completed five rounds of annual mass drug administration (MDA) with diethylcarbamazine citrate and albendazole as part of its national programme for elimination of lymphatic filariasis. Albendazole is also highly effective against soil-transmitted helminths (STH). This study was carried out to assess the impact of repeated annual MDA on STH infections in the Western Province of Sri Lanka, an area that is co-endemic for lymphatic filariasis and STH. A total of 17 schools in the Western Province were selected because they were included in a national survey of the health of school children in Grade 5 in 2003, when one round of MDA had been completed. Faecal samples were obtained again in 2006 (after five rounds of MDA), from one randomly selected class of Grade 5 students in the same schools. In both surveys, faecal samples were examined using the modified Kato-Katz technique. The prevalence and intensity of roundworm, whipworm and hookworm infections in 2003 and 2006 were compared using chi-square or Z-test for a difference between two percentages. Faecal samples from 255 children were examined in 2003; 448 were examined in 2006. Roundworm prevalence was marginally lower in 2006 (4.0%) than in 2003 (4.7%), as was hookworm (0.2% vs 0.4%) whereas whipworm prevalence was higher (13.8% vs 9.4%). Mean egg counts for all three infections were marginally higher in 2006. However, none of these differences were statistically significant. Compliance with MDA in 2006, as reported by the school children examined, was only 59%. These results indicate that four annual roundsof MDA with diethylcarbamazine and citrate and albendazole had virtually no impact on STH infections in the study area. It is likely that inclusion of of albendazole in MDA for lymphatic filariasis does not have much impact on STH infections in areas of low endemicity, unless very high coverage rates are achieved.
  • No Thumbnail Available
    Item
    The Effect of intestinal nematode infections on atopic diseases in children
    (Allergy and Immunology Society of Sri Lanka, 2009) Amarasekera, N.D.D.M.; Gunawardena, N.K.; de Silva, N.R.; Douglas, J.; O'Hehir, R.; Weerasinghe, A.
    BACKGROUND : The effect of helminth infections on atopic diseases and allergic sensitization is controversial. Little is known about the effect of infection on atopic diseases in children living in areas where both intestinal nematodes and Toxocara infections are prevalent. OBJECTIVE : To examine the association between atopic diseases and helminth infection among children exposed to both intestinal nematodes and Toxocara. METHODS: Children attending grade 5 (age group 9-11 years) in 17 schools in the Western Province of Sri Lanka were recruited. The association of atopic diseases (asthma, rhinitis, eczema) with active intestinal nematode infections (excreting eggs in faeces) and with exposure to Toxocara (specific IgG antibodies in serum) was investigated. A child was deemed sensitized if positive for at least one of the allergens tested (Dermatophagoides pteronyssinus, Blomia tropicalis, cockroach, cat epithelium, grass pollen), based on specific IgE levels in serum. RESULTS: A total of 640 children participated in the study; serum analysis was done in 203. Active intestinal nematode infection appeared to reduce the risk of atopic diseases (OR 0.47, P=0.016) whereas Toxocara exposure did not (OR 0.85 P=0.602). When specific IgE levels against Blomia tropicalis, the most common allergen in the study group (67.5%), were expressed as percentages of the total IgE levels for each child, infected children had significantly lower levels compared to uninfected children (P=0.001). CONCLUSIONS : Intestinal nematode infections seem to protect against atopic diseases in children in Sri Lanka. Polyclonal IgE synthesis may be involved in this protection.
  • No Thumbnail Available
    Item
    Reduced risk of atopic diseases among schoolchildren infected with intestinal Nematodes
    (Federation of Immunology Societies of Asia-Oceania, 2008) Amarasekera, N.D.D.M.; Gunawardena, N.K.; de Silva, N.R.; Pathmeswaran, A.; Douglass, J.; O’Hehir, R.; Weerasinghe, A.
    BACKGROUND: The effect of helminth infections on atopic diseases and allergic sensitization is controversial. Little is known about the effect of infection on atopic diseases in children living in areas where both intestinal nematodes and Toxocara infections are prevalent. OBJECTIVE : To examine the association between atopic diseases and helminth infection among children exposed to both intestinal nematodes and Toxocara. METHODS: Children attending grade 5 (age group 9-11 years) in 17 schools in the Western Province of Sri Lanka were recruited. The association of atopic diseases (asthma, rhinitis, eczema) with active intestinal nematode infections (excreting eggs in faeces) and with exposure to Toxocara (specific IgG antibodies in serum) was investigate. A child was deemed sensitized if positive for at least one of the allergens tested (Dermatophagoides pteronyssinus, Blomia tropicalis, cockroach, cat epithelium, grass pollen), based on specific IgE levels in serum. RESULTS : A total of 640 children participated in the study; serum analysis was done in 203. Active intestinal nematode infection appeared to reduce the risk of atopic diseases (OR 0.47, P=0.0I6) whereas Toxocara exposure did not (OR 0.85, P=0.602). When specific IgE levels against Blomia tropicalis, the most common allergen in the study group (67.5%), were expressed as percentages of the total IgE levels for each child, infected children had significantly lower levels compared to uninfected children (P=0.001). CONCLUSIONS : Intestinal nematode infections seem to protect against atopic diseases in children in the tropics. Polyclonal IgE synthesis may be involved in this protection.
  • No Thumbnail Available
    Item
    Association between serum total IgE, allergic diseases and geohelminth infections in Sri Lankan children
    (BioMed Central, 2007) Amarasekera, N.D.D.M.; Gunawardena, N.K.; de Silva, N.R.; Douglass, J.; O’Hehir, R.E.; Weerasinghe, A.
    BACKGROUND: Elevated levels of total IgE (tIgE) in serum are characteristic of allergic diseases. Levels of tIgE are influenced by genetic predisposition, age, sex and helminth infections. However, the association between tIgE and allergic diseases in children living in areas endemic for helminth infections is not clear. The aim of our study was to assess the relationship between tIgE, allergic diseases and geohelminth infections in children. METHODS: A total of 640 schoolchildren 9Y11 years of age was selected by stratified random sampling. Data regarding allergic diseases (asthma, rhinitis and eczema) were collected by a standard questionnaire given to the parent or guardian. Screening for helminth infections was done by examining their fresh stool samples by modified Kato-Katz technique. Serum tIgE was measured by Fluoroenzymeimmunoassay in 67 geohelminth-positive subjects and in a comparable group of geohelminth-negative subjects. RESULTS: The mean age in the study population was 10 years (SDT0.3). The prevalence of geohelminth infection was 15.5%. Trichuris trichiura (14.3%) was the most common followed by Ascaris lumbricoides (4.2%) and hookworm (0.2%). Mixed infection was detected in 20.3% of infected children. Infection intensity was light in 68.9% of infected children while 28.4% and 2.7% showed moderate and heavy infection respectively. The cumulative prevalence of allergic diseases was 33.7%. Prevalence of asthma, rhinitis and eczema was 17%, 21.4% and 5% respectively. Serum tIgE concentrations showed a positively skewed distribution. Geometric mean (GM) for tIgE for the geohelminth infected group (1039.9kU/L) was significantly higher than that of the non-infected group (575.4kU/L) (p = 0.004). It was also higher in the allergic group (933.3kU/L) than in the non-allergic group (639.7kU/L) but the difference was not statistically significant (p = 0.068). The GM for tIgE for non-allergic children in the study population was much higher than that seen in non-allergic children in developed countries. CONCLUSION: Serum tIgE concentration was strongly associated with the presence of geohelminth infections in children. Serum tIgE may not be a useful marker for allergic diseases in children living in areas endemic for geohelminth infections. © 2007 World Allergy Organization
  • No Thumbnail Available
    Item
    Controlling lymphatic filariasis and soil-transmitted helminthiasis together in South Asia: opportunities and challenges
    (Oxford University Press, 2006) Padmasiri, E.A.; Montresor, A.; Biswas, G.; de Silva, N.R.
  • No Thumbnail Available
    Item
    Making the best of what we have: a plea for wider use of anthelmintics
    (Indian Council of Medical Research, 2005) de Silva, N.
    No Abstract Available
  • No Thumbnail Available
    Item
    Geo-helminth infections in a rural area of Sri Lanka
    (SEAMEO Regional Tropical Medicine and Public Health Project, 2001) Fernando, S.D.; Goonethilleke, H.; Weerasena, K.H.; Kuruppuarachchi, N.D.; Tilakaratne, D.; de Silva, D.; Wickremasinghe, A.R.
    School children carry the heaviest burden of morbidity due to intestinal helminth infection. The objective of this investigation was to study geo-helminth infections in 349 school children aged 6 to 13 years living in a rural area of Sri Lanka. Stool samples were examined by direct saline smear in an initial survey to determine the prevalence of intestinal parasitic infections and thereafter the children were followed up over a two year period with cross sectional surveys of stool samples being carried out at yearly intervals. Following collection of a stool sample, all the subjects were treated with mebendazole 500 mg as a single dose. Weights and heights were measured using standardized procedures. 2 ml of venous blood were collected from each subject under aseptic conditions to determine hematological indices. The prevalence of geo-helminth infections was low, and the prevalence declined during the two-year period from 5.4 percent in 1997 to 2.2 percent in 1998 and 2.0 percent in 1999 following yearly mass anti-helminth treatment. The incidence density was 0.021 cases per child year. The reduction in the prevalence from the baseline to the second survey is probably due to the reduction of the reservoir of infection among children as a result of mass treatment at baseline. The prevalence of infection during the second and third surveys were almost the same probably due to infections originating from other segments of the untreated population.
  • No Thumbnail Available
    Item
    Morbidity due to intestinal geohelminth infections
    (2000) de Silva, H.J.; de Silva, N.R.
    No Abstract Available
All items in this Institutional Repository are protected by copyright, with all rights reserved, unless otherwise indicated. No item in the repository may be reproduced for commercial or resale purposes.