Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.

<h4>Background</h4>Recent studies in Mali, Nigeria, and Senegal have indicated that annual (or biannual) ivermectin distribution may lead to local elimination of human onchocerciasis in certain African foci. Modelling-based projections have been used to estimate the required duration of...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Hugo C Turner, Thomas S Churcher, Martin Walker, Mike Y Osei-Atweneboana, Roger K Prichard, María-Gloria Basáñez
Formato:	article
Lenguaje:	EN
Publicado:	Public Library of Science (PLoS) 2013
Materias:	Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270
Acceso en línea:	https://doaj.org/article/3071b230cfcd4e00a4ebffa8a627303a
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:3071b230cfcd4e00a4ebffa8a627303a
record_format	dspace
spelling	oai:doaj.org-article:3071b230cfcd4e00a4ebffa8a627303a2021-11-18T09:15:08ZUncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.1935-27271935-273510.1371/journal.pntd.0002169https://doaj.org/article/3071b230cfcd4e00a4ebffa8a627303a2013-01-01T00:00:00Zhttps://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23634234/pdf/?tool=EBIhttps://doaj.org/toc/1935-2727https://doaj.org/toc/1935-2735<h4>Background</h4>Recent studies in Mali, Nigeria, and Senegal have indicated that annual (or biannual) ivermectin distribution may lead to local elimination of human onchocerciasis in certain African foci. Modelling-based projections have been used to estimate the required duration of ivermectin distribution to reach elimination. A crucial assumption has been that microfilarial production by Onchocerca volvulus is reduced irreversibly by 30-35% with each (annual) ivermectin round. However, other modelling-based analyses suggest that ivermectin may not have such a cumulative effect. Uncertainty in this (biological) and other (programmatic) assumptions would affect projected outcomes of long-term ivermectin treatment.<h4>Methodology/principal findings</h4>We modify a deterministic age- and sex-structured onchocerciasis transmission model, parameterised for savannah O. volvulus-Simulium damnosum, to explore the impact of assumptions regarding the effect of ivermectin on worm fertility and the patterns of treatment coverage compliance, and frequency on projections of parasitological outcomes due to long-term, mass ivermectin administration in hyperendemic areas. The projected impact of ivermectin distribution on onchocerciasis and the benefits of switching from annual to biannual distribution are strongly dependent on assumptions regarding the drug's effect on worm fertility and on treatment compliance. If ivermectin does not have a cumulative impact on microfilarial production, elimination of onchocerciasis in hyperendemic areas may not be feasible with annual ivermectin distribution.<h4>Conclusions/significance</h4>There is substantial (biological and programmatic) uncertainty surrounding modelling projections of onchocerciasis elimination. These uncertainties need to be acknowledged for mathematical models to inform control policy reliably. Further research is needed to elucidate the effect of ivermectin on O. volvulus reproductive biology and quantify the patterns of coverage and compliance in treated communities.Hugo C TurnerThomas S ChurcherMartin WalkerMike Y Osei-AtweneboanaRoger K PrichardMaría-Gloria BasáñezPublic Library of Science (PLoS)articleArctic medicine. Tropical medicineRC955-962Public aspects of medicineRA1-1270ENPLoS Neglected Tropical Diseases, Vol 7, Iss 4, p e2169 (2013)
institution	DOAJ
collection	DOAJ
language	EN
topic	Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270
spellingShingle	Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Hugo C Turner Thomas S Churcher Martin Walker Mike Y Osei-Atweneboana Roger K Prichard María-Gloria Basáñez Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.
description	<h4>Background</h4>Recent studies in Mali, Nigeria, and Senegal have indicated that annual (or biannual) ivermectin distribution may lead to local elimination of human onchocerciasis in certain African foci. Modelling-based projections have been used to estimate the required duration of ivermectin distribution to reach elimination. A crucial assumption has been that microfilarial production by Onchocerca volvulus is reduced irreversibly by 30-35% with each (annual) ivermectin round. However, other modelling-based analyses suggest that ivermectin may not have such a cumulative effect. Uncertainty in this (biological) and other (programmatic) assumptions would affect projected outcomes of long-term ivermectin treatment.<h4>Methodology/principal findings</h4>We modify a deterministic age- and sex-structured onchocerciasis transmission model, parameterised for savannah O. volvulus-Simulium damnosum, to explore the impact of assumptions regarding the effect of ivermectin on worm fertility and the patterns of treatment coverage compliance, and frequency on projections of parasitological outcomes due to long-term, mass ivermectin administration in hyperendemic areas. The projected impact of ivermectin distribution on onchocerciasis and the benefits of switching from annual to biannual distribution are strongly dependent on assumptions regarding the drug's effect on worm fertility and on treatment compliance. If ivermectin does not have a cumulative impact on microfilarial production, elimination of onchocerciasis in hyperendemic areas may not be feasible with annual ivermectin distribution.<h4>Conclusions/significance</h4>There is substantial (biological and programmatic) uncertainty surrounding modelling projections of onchocerciasis elimination. These uncertainties need to be acknowledged for mathematical models to inform control policy reliably. Further research is needed to elucidate the effect of ivermectin on O. volvulus reproductive biology and quantify the patterns of coverage and compliance in treated communities.
format	article
author	Hugo C Turner Thomas S Churcher Martin Walker Mike Y Osei-Atweneboana Roger K Prichard María-Gloria Basáñez
author_facet	Hugo C Turner Thomas S Churcher Martin Walker Mike Y Osei-Atweneboana Roger K Prichard María-Gloria Basáñez
author_sort	Hugo C Turner
title	Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.
title_short	Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.
title_full	Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.
title_fullStr	Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.
title_full_unstemmed	Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.
title_sort	uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.
publisher	Public Library of Science (PLoS)
publishDate	2013
url	https://doaj.org/article/3071b230cfcd4e00a4ebffa8a627303a
work_keys_str_mv	AT hugocturner uncertaintysurroundingprojectionsofthelongtermimpactofivermectintreatmentonhumanonchocerciasis AT thomasschurcher uncertaintysurroundingprojectionsofthelongtermimpactofivermectintreatmentonhumanonchocerciasis AT martinwalker uncertaintysurroundingprojectionsofthelongtermimpactofivermectintreatmentonhumanonchocerciasis AT mikeyoseiatweneboana uncertaintysurroundingprojectionsofthelongtermimpactofivermectintreatmentonhumanonchocerciasis AT rogerkprichard uncertaintysurroundingprojectionsofthelongtermimpactofivermectintreatmentonhumanonchocerciasis AT mariagloriabasanez uncertaintysurroundingprojectionsofthelongtermimpactofivermectintreatmentonhumanonchocerciasis
_version_	1718420894594891776

Uncertainty surrounding projections of the long-term impact of ivermectin treatment on human onchocerciasis.

Ejemplares similares