Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.

<h4>Background</h4>The impact of insecticide treated nets (ITNs) on reducing malaria incidence is shown mainly through data collection from health facilities. Routine evaluation of long-term epidemiological and entomological dynamics is currently unavailable. In Kenya, new policies suppo...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Guofa Zhou, Yaw A Afrane, Anne M Vardo-Zalik, Harrysone Atieli, Daibin Zhong, Peter Wamae, Yousif E Himeidan, Noboru Minakawa, Andrew K Githeko, Guiyun Yan
Formato:	article
Lenguaje:	EN
Publicado:	Public Library of Science (PLoS) 2011
Materias:	Medicine R Science Q
Acceso en línea:	https://doaj.org/article/d00b73303a8e4f97ac428d93ac83ae22
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:d00b73303a8e4f97ac428d93ac83ae22
record_format	dspace
spelling	oai:doaj.org-article:d00b73303a8e4f97ac428d93ac83ae222021-11-18T06:53:26ZChanging patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.1932-620310.1371/journal.pone.0020318https://doaj.org/article/d00b73303a8e4f97ac428d93ac83ae222011-01-01T00:00:00Zhttps://www.ncbi.nlm.nih.gov/pmc/articles/pmid/21629783/?tool=EBIhttps://doaj.org/toc/1932-6203<h4>Background</h4>The impact of insecticide treated nets (ITNs) on reducing malaria incidence is shown mainly through data collection from health facilities. Routine evaluation of long-term epidemiological and entomological dynamics is currently unavailable. In Kenya, new policies supporting the provision of free ITNs were implemented nationwide in June 2006. To evaluate the impacts of ITNs on malaria transmission, we conducted monthly surveys in three sentinel sites with different transmission intensities in western Kenya from 2002 to 2010.<h4>Methods and findings</h4>Longitudinal samplings of malaria parasite prevalence in asymptomatic school children and vector abundance in randomly selected houses were undertaken monthly from February 2002. ITN ownership and usage surveys were conducted annually from 2004 to 2010. Asymptomatic malaria parasite prevalence and vector abundances gradually decreased in all three sites from 2002 to 2006, and parasite prevalence reached its lowest level from late 2006 to early 2007. The abundance of the major malaria vectors, Anopheles funestus and An. gambiae, increased about 5-10 folds in all study sites after 2007. However, the resurgence of vectors was highly variable between sites and species. By 2010, asymptomatic parasite prevalence in Kombewa had resurged to levels recorded in 2004/2005, but the resurgence was smaller in magnitude in the other sites. Household ITN ownership was at 50-70% in 2009, but the functional and effective bed net coverage in the population was estimated at 40.3%, 49.4% and 28.2% in 2010 in Iguhu, Kombewa, and Marani, respectively.<h4>Conclusion</h4>The resurgence in parasite prevalence and malaria vectors has been observed in two out of three sentinel sites in western Kenya despite a high ownership of ITNs. The likely factors contributing to malaria resurgence include reduced efficacy of ITNs, insecticide resistance in mosquitoes and lack of proper use of ITNs. These factors should be targeted to avoid further resurgence of malaria transmission.Guofa ZhouYaw A AfraneAnne M Vardo-ZalikHarrysone AtieliDaibin ZhongPeter WamaeYousif E HimeidanNoboru MinakawaAndrew K GithekoGuiyun YanPublic Library of Science (PLoS)articleMedicineRScienceQENPLoS ONE, Vol 6, Iss 5, p e20318 (2011)
institution	DOAJ
collection	DOAJ
language	EN
topic	Medicine R Science Q
spellingShingle	Medicine R Science Q Guofa Zhou Yaw A Afrane Anne M Vardo-Zalik Harrysone Atieli Daibin Zhong Peter Wamae Yousif E Himeidan Noboru Minakawa Andrew K Githeko Guiyun Yan Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.
description	<h4>Background</h4>The impact of insecticide treated nets (ITNs) on reducing malaria incidence is shown mainly through data collection from health facilities. Routine evaluation of long-term epidemiological and entomological dynamics is currently unavailable. In Kenya, new policies supporting the provision of free ITNs were implemented nationwide in June 2006. To evaluate the impacts of ITNs on malaria transmission, we conducted monthly surveys in three sentinel sites with different transmission intensities in western Kenya from 2002 to 2010.<h4>Methods and findings</h4>Longitudinal samplings of malaria parasite prevalence in asymptomatic school children and vector abundance in randomly selected houses were undertaken monthly from February 2002. ITN ownership and usage surveys were conducted annually from 2004 to 2010. Asymptomatic malaria parasite prevalence and vector abundances gradually decreased in all three sites from 2002 to 2006, and parasite prevalence reached its lowest level from late 2006 to early 2007. The abundance of the major malaria vectors, Anopheles funestus and An. gambiae, increased about 5-10 folds in all study sites after 2007. However, the resurgence of vectors was highly variable between sites and species. By 2010, asymptomatic parasite prevalence in Kombewa had resurged to levels recorded in 2004/2005, but the resurgence was smaller in magnitude in the other sites. Household ITN ownership was at 50-70% in 2009, but the functional and effective bed net coverage in the population was estimated at 40.3%, 49.4% and 28.2% in 2010 in Iguhu, Kombewa, and Marani, respectively.<h4>Conclusion</h4>The resurgence in parasite prevalence and malaria vectors has been observed in two out of three sentinel sites in western Kenya despite a high ownership of ITNs. The likely factors contributing to malaria resurgence include reduced efficacy of ITNs, insecticide resistance in mosquitoes and lack of proper use of ITNs. These factors should be targeted to avoid further resurgence of malaria transmission.
format	article
author	Guofa Zhou Yaw A Afrane Anne M Vardo-Zalik Harrysone Atieli Daibin Zhong Peter Wamae Yousif E Himeidan Noboru Minakawa Andrew K Githeko Guiyun Yan
author_facet	Guofa Zhou Yaw A Afrane Anne M Vardo-Zalik Harrysone Atieli Daibin Zhong Peter Wamae Yousif E Himeidan Noboru Minakawa Andrew K Githeko Guiyun Yan
author_sort	Guofa Zhou
title	Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.
title_short	Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.
title_full	Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.
title_fullStr	Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.
title_full_unstemmed	Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.
title_sort	changing patterns of malaria epidemiology between 2002 and 2010 in western kenya: the fall and rise of malaria.
publisher	Public Library of Science (PLoS)
publishDate	2011
url	https://doaj.org/article/d00b73303a8e4f97ac428d93ac83ae22
work_keys_str_mv	AT guofazhou changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT yawaafrane changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT annemvardozalik changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT harrysoneatieli changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT daibinzhong changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT peterwamae changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT yousifehimeidan changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT noboruminakawa changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT andrewkgitheko changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria AT guiyunyan changingpatternsofmalariaepidemiologybetween2002and2010inwesternkenyathefallandriseofmalaria
_version_	1718424258143584256

Changing patterns of malaria epidemiology between 2002 and 2010 in Western Kenya: the fall and rise of malaria.

Ejemplares similares