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Patterns of epidemiology and control of onchocerciasis in West Africa

Published online by Cambridge University Press:  05 June 2009

B. Boatin
Affiliation:
World Health Organization, Onchocerciasis Control Programme, BP 549, Ouagadougou, Burkina Faso:
D.H. Molyneux*
Affiliation:
Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK:
J.M. Hougard
Affiliation:
World Health Organization, Onchocerciasis Control Programme, BP 549, Ouagadougou, Burkina Faso:
O.W. Christensen
Affiliation:
World Health Organization, OCP Liaison Office, 1211 Geneva 27, Switzerland
E.S. Alley
Affiliation:
World Health Organization, Onchocerciasis Control Programme, BP 549, Ouagadougou, Burkina Faso:
L. Yameogo
Affiliation:
World Health Organization, Onchocerciasis Control Programme, BP 549, Ouagadougou, Burkina Faso:
A. Seketeli
Affiliation:
World Health Organization, Onchocerciasis Control Programme, BP 549, Ouagadougou, Burkina Faso:
K.Y. Dadzie
Affiliation:
World Health Organization, Onchocerciasis Control Programme, BP 549, Ouagadougou, Burkina Faso:
*
*Author for correspondence.

Abstract

This paper summarizes the work of the Onchocerciasis Control Programme (OCP) in West Africa, a programme which over a 22 year history has reduced the public health problems of blinding onchocerciasis in eleven countries of West Africa through vector control and, more recently, ivermectin distribution. The paper emphasizes the different approaches to control the programme has developed in the different parts of the programme area which have been determined by the epidemiology of the disease (savanna/forest form), the migratory characteristics of the vectors, intensity of the disease before commencement of treatment, the combined impact of vector control and ivermectin and the likelihood of infiltration of infective blackflies from outside the programme area. The programme has constantly monitored the impact of operations on the trends in prevalence, incidence, annual transmission potential, ocular morbidity and species of fly populations, and as a result, has identified areas where special interventions are required until the programme comes to an end in 2002. The paper illustrates the changes in intensity of infection as measured by community microfilarial load and annual transmission potential over the duration of the programme control activities. The paper also defines and justifies the control strategies in different areas and identifies areas for special interventions.

Type
Symposium Papers
Copyright
Copyright © Cambridge University Press 1997

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