Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model.
BACKGROUND: Urinary Schistosomiasis infection, a common cause of morbidity especially among children in less developed countries, is measured by the number of eggs per urine. Typically a large proportion of individuals are non-egg excretors, leading to a large number of zeros. Control strategies req...
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ftdoajarticles:oai:doaj.org/article:c76bbb3c742b4692ac3842cb5c7bbda7 2023-05-15T15:14:15+02:00 Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model. Michael G Chipeta Bagrey Ngwira Lawrence N Kazembe 2013-01-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0002131 https://doaj.org/article/c76bbb3c742b4692ac3842cb5c7bbda7 EN eng Public Library of Science (PLoS) http://europepmc.org/articles/PMC3605235?pdf=render https://doaj.org/toc/1935-2735 1935-2735 doi:10.1371/journal.pntd.0002131 https://doaj.org/article/c76bbb3c742b4692ac3842cb5c7bbda7 PLoS Neglected Tropical Diseases, Vol 7, Iss 3, p e2131 (2013) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2013 ftdoajarticles https://doi.org/10.1371/journal.pntd.0002131 2022-12-31T07:29:19Z BACKGROUND: Urinary Schistosomiasis infection, a common cause of morbidity especially among children in less developed countries, is measured by the number of eggs per urine. Typically a large proportion of individuals are non-egg excretors, leading to a large number of zeros. Control strategies require better understanding of its epidemiology, hence appropriate methods to model infection prevalence and intensity are crucial, particularly if such methods add value to targeted implementation of interventions. METHODS: We consider data that were collected in a cluster randomized study in 2004 in Chikhwawa district, Malawi, where eighteen (18) villages were selected and randomised to intervention and control arms. We developed a two-part model, with one part for analysis of infection prevalence and the other to model infection intensity. In both parts of the model we adjusted for age, sex, education level, treatment arm, occupation, and poly-parasitism. We also assessed for spatial correlation in the model residual using variogram analysis and mapped the spatial variation in risk. The model was fitted using maximum likelihood estimation. RESULTS AND DISCUSSION: The study had a total of 1642 participants with mean age of 32.4 (Standard deviation: 22.8), of which 55.4 % were female. Schistosomiasis prevalence was 14.2 %, with a large proportion of individuals (85.8 %) being non-egg excretors, hence zero-inflated data. Our findings showed that S. haematobium was highly localized even after adjusting for risk factors. Prevalence of infection was low in males as compared to females across all the age ranges. S. haematobium infection increased with presence of co-infection with other parasite infection. Infection intensity was highly associated with age; with highest intensity in school-aged children (6 to 15 years). Fishing and working in gardens along the Shire River were potential risk factors for S. haematobium infection intensity. Intervention reduced both infection intensity and prevalence in the intervention arm ... Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLoS Neglected Tropical Diseases 7 3 e2131 |
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Directory of Open Access Journals: DOAJ Articles |
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English |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Michael G Chipeta Bagrey Ngwira Lawrence N Kazembe Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model. |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
BACKGROUND: Urinary Schistosomiasis infection, a common cause of morbidity especially among children in less developed countries, is measured by the number of eggs per urine. Typically a large proportion of individuals are non-egg excretors, leading to a large number of zeros. Control strategies require better understanding of its epidemiology, hence appropriate methods to model infection prevalence and intensity are crucial, particularly if such methods add value to targeted implementation of interventions. METHODS: We consider data that were collected in a cluster randomized study in 2004 in Chikhwawa district, Malawi, where eighteen (18) villages were selected and randomised to intervention and control arms. We developed a two-part model, with one part for analysis of infection prevalence and the other to model infection intensity. In both parts of the model we adjusted for age, sex, education level, treatment arm, occupation, and poly-parasitism. We also assessed for spatial correlation in the model residual using variogram analysis and mapped the spatial variation in risk. The model was fitted using maximum likelihood estimation. RESULTS AND DISCUSSION: The study had a total of 1642 participants with mean age of 32.4 (Standard deviation: 22.8), of which 55.4 % were female. Schistosomiasis prevalence was 14.2 %, with a large proportion of individuals (85.8 %) being non-egg excretors, hence zero-inflated data. Our findings showed that S. haematobium was highly localized even after adjusting for risk factors. Prevalence of infection was low in males as compared to females across all the age ranges. S. haematobium infection increased with presence of co-infection with other parasite infection. Infection intensity was highly associated with age; with highest intensity in school-aged children (6 to 15 years). Fishing and working in gardens along the Shire River were potential risk factors for S. haematobium infection intensity. Intervention reduced both infection intensity and prevalence in the intervention arm ... |
format |
Article in Journal/Newspaper |
author |
Michael G Chipeta Bagrey Ngwira Lawrence N Kazembe |
author_facet |
Michael G Chipeta Bagrey Ngwira Lawrence N Kazembe |
author_sort |
Michael G Chipeta |
title |
Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model. |
title_short |
Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model. |
title_full |
Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model. |
title_fullStr |
Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model. |
title_full_unstemmed |
Analysis of Schistosomiasis haematobium infection prevalence and intensity in Chikhwawa, Malawi: an application of a two part model. |
title_sort |
analysis of schistosomiasis haematobium infection prevalence and intensity in chikhwawa, malawi: an application of a two part model. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2013 |
url |
https://doi.org/10.1371/journal.pntd.0002131 https://doaj.org/article/c76bbb3c742b4692ac3842cb5c7bbda7 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 7, Iss 3, p e2131 (2013) |
op_relation |
http://europepmc.org/articles/PMC3605235?pdf=render https://doaj.org/toc/1935-2735 1935-2735 doi:10.1371/journal.pntd.0002131 https://doaj.org/article/c76bbb3c742b4692ac3842cb5c7bbda7 |
op_doi |
https://doi.org/10.1371/journal.pntd.0002131 |
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PLoS Neglected Tropical Diseases |
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7 |
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3 |
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e2131 |
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