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The geographic distribution of loa loa in Africa: results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA)

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The geographic distribution of loa loa in Africa: results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA). / Zoure, Honorat Gustave Marie; Wanji, Samuel; Noma, Mounkaila et al.
In: PLoS Neglected Tropical Diseases, Vol. 5, No. 6, e1210, 06.2011, p. -.

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Zoure, HGM, Wanji, S, Noma, M, Amazigo, UV, Diggle, PJ, Tekle, AH & Remme, JHF 2011, 'The geographic distribution of loa loa in Africa: results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA)', PLoS Neglected Tropical Diseases, vol. 5, no. 6, e1210, pp. -. https://doi.org/10.1371/journal.pntd.0001210

APA

Zoure, H. G. M., Wanji, S., Noma, M., Amazigo, U. V., Diggle, P. J., Tekle, A. H., & Remme, J. H. F. (2011). The geographic distribution of loa loa in Africa: results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA). PLoS Neglected Tropical Diseases, 5(6), -. Article e1210. https://doi.org/10.1371/journal.pntd.0001210

Vancouver

Zoure HGM, Wanji S, Noma M, Amazigo UV, Diggle PJ, Tekle AH et al. The geographic distribution of loa loa in Africa: results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA). PLoS Neglected Tropical Diseases. 2011 Jun;5(6):-. e1210. doi: 10.1371/journal.pntd.0001210

Author

Zoure, Honorat Gustave Marie ; Wanji, Samuel ; Noma, Mounkaila et al. / The geographic distribution of loa loa in Africa : results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA). In: PLoS Neglected Tropical Diseases. 2011 ; Vol. 5, No. 6. pp. -.

Bibtex

@article{1c9c1ffcea1148de8f2e0dbea91bcd67,
title = "The geographic distribution of loa loa in Africa: results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA)",
abstract = "Background: Loiasis is a major obstacle to ivermectin treatment for onchocerciasis control and lymphatic filariasis elimination in central Africa. In communities with a high level of loiasis endemicity, there is a significant risk of severe adverse reactions to ivermectin treatment. Information on the geographic distribution of loiasis in Africa is urgently needed but available information is limited. The African Programme for Onchocerciasis Control (APOC) undertook large scale mapping of loiasis in 11 potentially endemic countries using a rapid assessment procedure for loiasis (RAPLOA) that uses a simple questionnaire on the history of eye worm. Methodology/Principal Findings: RAPLOA surveys were done in a spatial sample of 4798 villages covering an area of 250063000 km centred on the heartland of loiasis in Africa. The surveys showed high risk levels of loiasis in 10 countries where an estimated 14.4 million people live in high risk areas. There was a strong spatial correlation among RAPLOA data, and kriging was used to produce spatially smoothed contour maps of the interpolated prevalence of eye worm and the predictive probability that the prevalence exceeds 40%. Conclusion/Significance: The contour map of eye worm prevalence provides the first global map of loiasis based on actual survey data. It shows a clear distribution with two zones of hyper endemicity, large areas that are free of loiasis and several borderline or intermediate zones. The surveys detected several previously unknown hyperendemic foci, clarified the distribution of loiasis in the Central African Republic and large parts of the Republic of Congo and the Democratic Republic of Congo for which hardly any information was available, and confirmed known loiasis foci. The new maps of the prevalence of eye worm and the probability that the prevalence exceeds the risk threshold of 40% provide critical information for ivermectin treatment programs among millions of people in Africa.",
keywords = "MASS TREATMENT, HUMAN FILARIASIS, ENDEMIC AREAS, PREVALENCE, INFECTION, IVERMECTIN, CAMEROON, LOAIASIS, ONCHOCERCIASIS, INTENSITY",
author = "Zoure, {Honorat Gustave Marie} and Samuel Wanji and Mounkaila Noma and Amazigo, {Uche Veronica} and Diggle, {Peter J.} and Tekle, {Afework Hailemariam} and Remme, {Jan H. F.}",
year = "2011",
month = jun,
doi = "10.1371/journal.pntd.0001210",
language = "English",
volume = "5",
pages = "--",
journal = "PLoS Neglected Tropical Diseases",
publisher = "Public Library of Science",
number = "6",

}

RIS

TY - JOUR

T1 - The geographic distribution of loa loa in Africa

T2 - results of large-scale implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA)

AU - Zoure, Honorat Gustave Marie

AU - Wanji, Samuel

AU - Noma, Mounkaila

AU - Amazigo, Uche Veronica

AU - Diggle, Peter J.

AU - Tekle, Afework Hailemariam

AU - Remme, Jan H. F.

PY - 2011/6

Y1 - 2011/6

N2 - Background: Loiasis is a major obstacle to ivermectin treatment for onchocerciasis control and lymphatic filariasis elimination in central Africa. In communities with a high level of loiasis endemicity, there is a significant risk of severe adverse reactions to ivermectin treatment. Information on the geographic distribution of loiasis in Africa is urgently needed but available information is limited. The African Programme for Onchocerciasis Control (APOC) undertook large scale mapping of loiasis in 11 potentially endemic countries using a rapid assessment procedure for loiasis (RAPLOA) that uses a simple questionnaire on the history of eye worm. Methodology/Principal Findings: RAPLOA surveys were done in a spatial sample of 4798 villages covering an area of 250063000 km centred on the heartland of loiasis in Africa. The surveys showed high risk levels of loiasis in 10 countries where an estimated 14.4 million people live in high risk areas. There was a strong spatial correlation among RAPLOA data, and kriging was used to produce spatially smoothed contour maps of the interpolated prevalence of eye worm and the predictive probability that the prevalence exceeds 40%. Conclusion/Significance: The contour map of eye worm prevalence provides the first global map of loiasis based on actual survey data. It shows a clear distribution with two zones of hyper endemicity, large areas that are free of loiasis and several borderline or intermediate zones. The surveys detected several previously unknown hyperendemic foci, clarified the distribution of loiasis in the Central African Republic and large parts of the Republic of Congo and the Democratic Republic of Congo for which hardly any information was available, and confirmed known loiasis foci. The new maps of the prevalence of eye worm and the probability that the prevalence exceeds the risk threshold of 40% provide critical information for ivermectin treatment programs among millions of people in Africa.

AB - Background: Loiasis is a major obstacle to ivermectin treatment for onchocerciasis control and lymphatic filariasis elimination in central Africa. In communities with a high level of loiasis endemicity, there is a significant risk of severe adverse reactions to ivermectin treatment. Information on the geographic distribution of loiasis in Africa is urgently needed but available information is limited. The African Programme for Onchocerciasis Control (APOC) undertook large scale mapping of loiasis in 11 potentially endemic countries using a rapid assessment procedure for loiasis (RAPLOA) that uses a simple questionnaire on the history of eye worm. Methodology/Principal Findings: RAPLOA surveys were done in a spatial sample of 4798 villages covering an area of 250063000 km centred on the heartland of loiasis in Africa. The surveys showed high risk levels of loiasis in 10 countries where an estimated 14.4 million people live in high risk areas. There was a strong spatial correlation among RAPLOA data, and kriging was used to produce spatially smoothed contour maps of the interpolated prevalence of eye worm and the predictive probability that the prevalence exceeds 40%. Conclusion/Significance: The contour map of eye worm prevalence provides the first global map of loiasis based on actual survey data. It shows a clear distribution with two zones of hyper endemicity, large areas that are free of loiasis and several borderline or intermediate zones. The surveys detected several previously unknown hyperendemic foci, clarified the distribution of loiasis in the Central African Republic and large parts of the Republic of Congo and the Democratic Republic of Congo for which hardly any information was available, and confirmed known loiasis foci. The new maps of the prevalence of eye worm and the probability that the prevalence exceeds the risk threshold of 40% provide critical information for ivermectin treatment programs among millions of people in Africa.

KW - MASS TREATMENT

KW - HUMAN FILARIASIS

KW - ENDEMIC AREAS

KW - PREVALENCE

KW - INFECTION

KW - IVERMECTIN

KW - CAMEROON

KW - LOAIASIS

KW - ONCHOCERCIASIS

KW - INTENSITY

U2 - 10.1371/journal.pntd.0001210

DO - 10.1371/journal.pntd.0001210

M3 - Journal article

VL - 5

SP - -

JO - PLoS Neglected Tropical Diseases

JF - PLoS Neglected Tropical Diseases

IS - 6

M1 - e1210

ER -