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Published in: BMC Medicine 1/2007

Open Access 01-12-2007 | Research article

Impact of long-term treatment of onchocerciasis with ivermectin in Ecuador: potential for elimination of infection

Authors: Juan Carlos Vieira, Philip J Cooper, Raquel Lovato, Tamara Mancero, Jorge Rivera, Roberto Proaño, Andrea A López, Ronald H Guderian, José Rumbea Guzmán

Published in: BMC Medicine | Issue 1/2007

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Abstract

Background

Onchocerciasis is a leading cause of blindness worldwide, hence elimination of the infection is an important health priority. Community-based treatment programs with ivermectin form the basis of control programs for the disease in Latin America. The long-term administration of ivermectin could eliminate Onchocerca volvulus infection from endemic areas in Latin America.

Methods

A strategy of annual to twice-annual treatments with ivermectin has been used for onchocerciasis in endemic communities in Ecuador for up to 14 years. The impact of ivermectin treatment on ocular morbidity, and O. volvulus infection and transmission was monitored in seven sentinel communities.

Results

Over the period 1990–2003, high rates of treatment coverage of the eligible population were maintained in endemic communities (mean 85.2% per treatment round). Ivermectin reduced the prevalence of anterior segment disease of the eye to 0% in sentinel communities and had a major impact on the prevalence and transmission of infection, with possible elimination of infection in some foci.

Conclusion

The distribution of ivermectin in endemic communities in Ecuador might have eliminated ocular morbidity and significant progress has been made towards elimination of the infection. A strategy of more frequent treatments with ivermectin may be required in communities where the infection persists to achieve the objective of elimination of the infection from Ecuador. The elimination of the infection from an endemic country in Latin America would be a major public health achievement and could stimulate the implementation of elimination strategies in other endemic countries.
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Metadata
Title
Impact of long-term treatment of onchocerciasis with ivermectin in Ecuador: potential for elimination of infection
Authors
Juan Carlos Vieira
Philip J Cooper
Raquel Lovato
Tamara Mancero
Jorge Rivera
Roberto Proaño
Andrea A López
Ronald H Guderian
José Rumbea Guzmán
Publication date
01-12-2007
Publisher
BioMed Central
Published in
BMC Medicine / Issue 1/2007
Electronic ISSN: 1741-7015
DOI
https://doi.org/10.1186/1741-7015-5-9

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