Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya
To investigate the effects of irrigation on land cover changes and the risk of selected zoonotic pathogens, we carried out a study in irrigated, pastoral and riverine areas in the eastern Kenya. Activities implemented included secondary data analyses to determine land use and land cover (LULC) changes as well as human, livestock and wildlife population trends; entomological surveys to characterize mosquitoes population densities and species distribution by habitat and season; and serological surveys in people to determine the risk of Rift Valley fever virus (RVFV), West Nile fever virus (WNV), dengue fever virus (DFV), Leptospira spp. and Brucella spp. Results demonstrate a drastic decline in vegetation cover over ≈25 years particularly in the irrigated areas where cropland increased by about 1,400% and non-farm land (under closed trees, open to closed herbaceous vegetation, bushlands and open trees) reduced by 30–100%. The irrigated areas had high densities of Aedes mcintoshi, Culex spp. and Mansonia spp. (important vectors for multiple arboviruses) during the wet and dry season while pastoral areas had high densities of Ae. tricholabis specifically in the wet season. The seroprevalences of RVFV, WNV and DFV were higher in the irrigated compared to the pastoral areas while those for Leptospira spp and Brucella spp. were higher in the pastoral compared to the irrigated areas. It is likely that people in the pastoral areas get exposed to Leptospira spp by using water fetched from reservoirs that are shared with livestock and wildlife, and to Brucella spp. by consuming raw or partially cooked animal-source foods such as milk and meat. This study suggests that irrigation increases the risk of mosquito-borne infections while at the same time providing a protective effect against zoonotic pathogens that thrive in areas with high livestock population densities.
Main Authors: | , , , , , , , , , , |
---|---|
Format: | Journal Article biblioteca |
Language: | English |
Published: |
Public Library of Science
2017-05-31
|
Subjects: | epidemiology, health, zoonoses, |
Online Access: | https://hdl.handle.net/10568/81512 https://doi.org/10.1371/journal.pone.0172626 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
id |
dig-cgspace-10568-81512 |
---|---|
record_format |
koha |
spelling |
dig-cgspace-10568-815122023-12-08T19:36:04Z Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya Bett, Bernard K. Said, Mohammed Yahya Sang, R. Bukachi, S. Wanyoike, S. Kifugo, S.C. Otieno, Fredrick T. Ontiri, E. Njeru, I. Lindahl, Johanna F. Grace, Delia epidemiology health zoonoses To investigate the effects of irrigation on land cover changes and the risk of selected zoonotic pathogens, we carried out a study in irrigated, pastoral and riverine areas in the eastern Kenya. Activities implemented included secondary data analyses to determine land use and land cover (LULC) changes as well as human, livestock and wildlife population trends; entomological surveys to characterize mosquitoes population densities and species distribution by habitat and season; and serological surveys in people to determine the risk of Rift Valley fever virus (RVFV), West Nile fever virus (WNV), dengue fever virus (DFV), Leptospira spp. and Brucella spp. Results demonstrate a drastic decline in vegetation cover over ≈25 years particularly in the irrigated areas where cropland increased by about 1,400% and non-farm land (under closed trees, open to closed herbaceous vegetation, bushlands and open trees) reduced by 30–100%. The irrigated areas had high densities of Aedes mcintoshi, Culex spp. and Mansonia spp. (important vectors for multiple arboviruses) during the wet and dry season while pastoral areas had high densities of Ae. tricholabis specifically in the wet season. The seroprevalences of RVFV, WNV and DFV were higher in the irrigated compared to the pastoral areas while those for Leptospira spp and Brucella spp. were higher in the pastoral compared to the irrigated areas. It is likely that people in the pastoral areas get exposed to Leptospira spp by using water fetched from reservoirs that are shared with livestock and wildlife, and to Brucella spp. by consuming raw or partially cooked animal-source foods such as milk and meat. This study suggests that irrigation increases the risk of mosquito-borne infections while at the same time providing a protective effect against zoonotic pathogens that thrive in areas with high livestock population densities. 2017-05-31 2017-06-12T07:22:16Z 2017-06-12T07:22:16Z Journal Article Bett, B., Said, M.Y., Sang, R., Bukachi, S., Wanyoike, S., Kifugo, S.C., Otieno, F., Ontiri, E., Njeru, I., Lindahl, J. and Grace, D. 2017. Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya. PLOS ONE 12(5): e0172626. 1932-6203 https://hdl.handle.net/10568/81512 https://doi.org/10.1371/journal.pone.0172626 en CC-BY-4.0 Open Access Public Library of Science PLOS ONE |
institution |
CGIAR |
collection |
DSpace |
country |
Francia |
countrycode |
FR |
component |
Bibliográfico |
access |
En linea |
databasecode |
dig-cgspace |
tag |
biblioteca |
region |
Europa del Oeste |
libraryname |
Biblioteca del CGIAR |
language |
English |
topic |
epidemiology health zoonoses epidemiology health zoonoses |
spellingShingle |
epidemiology health zoonoses epidemiology health zoonoses Bett, Bernard K. Said, Mohammed Yahya Sang, R. Bukachi, S. Wanyoike, S. Kifugo, S.C. Otieno, Fredrick T. Ontiri, E. Njeru, I. Lindahl, Johanna F. Grace, Delia Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya |
description |
To investigate the effects of irrigation on land cover changes and the risk of selected zoonotic pathogens, we carried out a study in irrigated, pastoral and riverine areas in the eastern Kenya. Activities implemented included secondary data analyses to determine land use and land cover (LULC) changes as well as human, livestock and wildlife population trends; entomological surveys to characterize mosquitoes population densities and species distribution by habitat and season; and serological surveys in people to determine the risk of Rift Valley fever virus (RVFV), West Nile fever virus (WNV), dengue fever virus (DFV), Leptospira spp. and Brucella spp. Results demonstrate a drastic decline in vegetation cover over ≈25 years particularly in the irrigated areas where cropland increased by about 1,400% and non-farm land (under closed trees, open to closed herbaceous vegetation, bushlands and open trees) reduced by 30–100%. The irrigated areas had high densities of Aedes mcintoshi, Culex spp. and Mansonia spp. (important vectors for multiple arboviruses) during the wet and dry season while pastoral areas had high densities of Ae. tricholabis specifically in the wet season. The seroprevalences of RVFV, WNV and DFV were higher in the irrigated compared to the pastoral areas while those for Leptospira spp and Brucella spp. were higher in the pastoral compared to the irrigated areas. It is likely that people in the pastoral areas get exposed to Leptospira spp by using water fetched from reservoirs that are shared with livestock and wildlife, and to Brucella spp. by consuming raw or partially cooked animal-source foods such as milk and meat. This study suggests that irrigation increases the risk of mosquito-borne infections while at the same time providing a protective effect against zoonotic pathogens that thrive in areas with high livestock population densities. |
format |
Journal Article |
topic_facet |
epidemiology health zoonoses |
author |
Bett, Bernard K. Said, Mohammed Yahya Sang, R. Bukachi, S. Wanyoike, S. Kifugo, S.C. Otieno, Fredrick T. Ontiri, E. Njeru, I. Lindahl, Johanna F. Grace, Delia |
author_facet |
Bett, Bernard K. Said, Mohammed Yahya Sang, R. Bukachi, S. Wanyoike, S. Kifugo, S.C. Otieno, Fredrick T. Ontiri, E. Njeru, I. Lindahl, Johanna F. Grace, Delia |
author_sort |
Bett, Bernard K. |
title |
Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya |
title_short |
Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya |
title_full |
Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya |
title_fullStr |
Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya |
title_full_unstemmed |
Effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern Kenya |
title_sort |
effects of flood irrigation on the risk of selected zoonotic pathogens in an arid and semi-arid area in the eastern kenya |
publisher |
Public Library of Science |
publishDate |
2017-05-31 |
url |
https://hdl.handle.net/10568/81512 https://doi.org/10.1371/journal.pone.0172626 |
work_keys_str_mv |
AT bettbernardk effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT saidmohammedyahya effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT sangr effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT bukachis effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT wanyoikes effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT kifugosc effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT otienofredrickt effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT ontirie effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT njerui effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT lindahljohannaf effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya AT gracedelia effectsoffloodirrigationontheriskofselectedzoonoticpathogensinanaridandsemiaridareaintheeasternkenya |
_version_ |
1787229119410339840 |