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The development and validation of an age-structured model for the evaluation of disease control strategies for intestinal helminths

Published online by Cambridge University Press:  06 April 2009

M. S. Chan
Affiliation:
WHO Collaborating Centre for the Epidemiology of Intestinal Parasitic Infections, Department of Biology, ImperialCollege, London SW7 2BB, UK
H. L. Guyatt
Affiliation:
Swiss Tropical Institute, Socinstrasse 57, CH 4002 Basel, Switzerland
D. A. P. Bundy
Affiliation:
WHO Collaborating Centre for the Epidemiology of Intestinal Parasitic Infections, Department of Biology, ImperialCollege, London SW7 2BB, UK
G. F. Medley
Affiliation:
Analysis and Management Group, Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK

Summary

Epidemiological modelling can be a useful tool for the evaluation of parasite control strategies. An age-structured epidemiological model of intestinal helminth dynamics is developed. This model includes the explicit representation of changing worm distributions between hosts as a result of treatment, and estimates the morbidity due to heavy infections. The model is used to evaluate the effectiveness of different programmes of age-targeted community chemotherapy in reducing the amount of morbidity due to helminth infection. The magnitude of age-related heterogeneities is found to be very important in determining the results of age-targeted treatment programmes. The model was verified using field data from control programmes for Ascaris lumbricoides and Trichuris trichiura, and was found to provide accurate predictions of prevalence and mean intensities of infection during and following different control regimes.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1994

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