Cargando…

Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak

BACKGROUND: African swine fever (ASF), caused by African swine fever virus (ASFV), is a severe haemorrhagic disease of pigs, outbreaks of which can have a devastating impact upon commercial and small-holder pig production. Pig production in western Kenya is characterised by low-input, free-range sys...

Descripción completa

Detalles Bibliográficos
Autores principales: Thomas, Lian F., Bishop, Richard P., Onzere, Cynthia, Mcintosh, Michael T., Lemire, Karissa A., de Glanville, William A., Cook, E. Anne J., Fèvre, Eric M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5016997/
https://www.ncbi.nlm.nih.gov/pubmed/27608711
http://dx.doi.org/10.1186/s12917-016-0830-5
_version_ 1782452662121267200
author Thomas, Lian F.
Bishop, Richard P.
Onzere, Cynthia
Mcintosh, Michael T.
Lemire, Karissa A.
de Glanville, William A.
Cook, E. Anne J.
Fèvre, Eric M.
author_facet Thomas, Lian F.
Bishop, Richard P.
Onzere, Cynthia
Mcintosh, Michael T.
Lemire, Karissa A.
de Glanville, William A.
Cook, E. Anne J.
Fèvre, Eric M.
author_sort Thomas, Lian F.
collection PubMed
description BACKGROUND: African swine fever (ASF), caused by African swine fever virus (ASFV), is a severe haemorrhagic disease of pigs, outbreaks of which can have a devastating impact upon commercial and small-holder pig production. Pig production in western Kenya is characterised by low-input, free-range systems practised by poor farmers keeping between two and ten pigs. These farmers are particularly vulnerable to the catastrophic loss of livestock assets experienced in an ASF outbreak. This study wished to expand our understanding of ASFV epidemiology during a period when no outbreaks were reported. RESULTS: Two hundred and seventy six whole blood samples were analysed using two independent conventional and real time PCR assays to detect ASFV. Despite no recorded outbreak of clinical ASF during this time, virus was detected in 90/277 samples analysed by conventional PCR and 142/209 samples analysed by qPCR. Genotyping of a sub-set of these samples indicated that the viruses associated with the positive samples were classified within genotype IX and that these strains were therefore genetically similar to the virus associated with the 2006/2007 ASF outbreaks in Kenya. CONCLUSION: The detection of ASFV viral DNA in a relatively high number of pigs delivered for slaughter during a period with no reported outbreaks provides support for two hypotheses, which are not mutually exclusive: (1) that virus prevalence may be over-estimated by slaughter-slab sampling, relative to that prevailing in the wider pig population; (2) that sub-clinical, chronically infected or recovered pigs may be responsible for persistence of the virus in endemic areas. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12917-016-0830-5) contains supplementary material, which is available to authorized users.
format Online
Article
Text
id pubmed-5016997
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-50169972016-09-10 Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak Thomas, Lian F. Bishop, Richard P. Onzere, Cynthia Mcintosh, Michael T. Lemire, Karissa A. de Glanville, William A. Cook, E. Anne J. Fèvre, Eric M. BMC Vet Res Research Article BACKGROUND: African swine fever (ASF), caused by African swine fever virus (ASFV), is a severe haemorrhagic disease of pigs, outbreaks of which can have a devastating impact upon commercial and small-holder pig production. Pig production in western Kenya is characterised by low-input, free-range systems practised by poor farmers keeping between two and ten pigs. These farmers are particularly vulnerable to the catastrophic loss of livestock assets experienced in an ASF outbreak. This study wished to expand our understanding of ASFV epidemiology during a period when no outbreaks were reported. RESULTS: Two hundred and seventy six whole blood samples were analysed using two independent conventional and real time PCR assays to detect ASFV. Despite no recorded outbreak of clinical ASF during this time, virus was detected in 90/277 samples analysed by conventional PCR and 142/209 samples analysed by qPCR. Genotyping of a sub-set of these samples indicated that the viruses associated with the positive samples were classified within genotype IX and that these strains were therefore genetically similar to the virus associated with the 2006/2007 ASF outbreaks in Kenya. CONCLUSION: The detection of ASFV viral DNA in a relatively high number of pigs delivered for slaughter during a period with no reported outbreaks provides support for two hypotheses, which are not mutually exclusive: (1) that virus prevalence may be over-estimated by slaughter-slab sampling, relative to that prevailing in the wider pig population; (2) that sub-clinical, chronically infected or recovered pigs may be responsible for persistence of the virus in endemic areas. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12917-016-0830-5) contains supplementary material, which is available to authorized users. BioMed Central 2016-09-08 /pmc/articles/PMC5016997/ /pubmed/27608711 http://dx.doi.org/10.1186/s12917-016-0830-5 Text en © The Author(s). 2016 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research Article
Thomas, Lian F.
Bishop, Richard P.
Onzere, Cynthia
Mcintosh, Michael T.
Lemire, Karissa A.
de Glanville, William A.
Cook, E. Anne J.
Fèvre, Eric M.
Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak
title Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak
title_full Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak
title_fullStr Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak
title_full_unstemmed Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak
title_short Evidence for the presence of African swine fever virus in an endemic region of Western Kenya in the absence of any reported outbreak
title_sort evidence for the presence of african swine fever virus in an endemic region of western kenya in the absence of any reported outbreak
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5016997/
https://www.ncbi.nlm.nih.gov/pubmed/27608711
http://dx.doi.org/10.1186/s12917-016-0830-5
work_keys_str_mv AT thomaslianf evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak
AT bishoprichardp evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak
AT onzerecynthia evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak
AT mcintoshmichaelt evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak
AT lemirekarissaa evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak
AT deglanvillewilliama evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak
AT cookeannej evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak
AT fevreericm evidenceforthepresenceofafricanswinefevervirusinanendemicregionofwesternkenyaintheabsenceofanyreportedoutbreak