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Abebe S, Melaku H, Kidanu AG, Tschopp R. Pastoralism and Resulting Challenges for National Parks in Afar, Ethiopia. ECOHEALTH 2024:10.1007/s10393-024-01687-6. [PMID: 38819755 DOI: 10.1007/s10393-024-01687-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/26/2024] [Accepted: 05/09/2024] [Indexed: 06/01/2024]
Abstract
Pastoralists and national parks are key stakeholders in the management and conservation of natural and protected habitats. In Ethiopia, Afar pastoralists migrate seasonally with their livestock in search for grazing and water areas. Livestock are also a source of infectious diseases that can spread into wildlife populations when pastoralists encroach into unfenced national parks. The interactions between pastoralists and national parks, as well as the subsequent impacts, remain insufficiently understood in Afar. Two structured questionnaire surveys were conducted in 2021, including 300 pastoralist households in seven woredas of Afar, and 58 staff from three national parks (Awash, Alidegi and Yangudi Rassa). They captured pastoralist movements and livestock diseases as well as the perception of national park staff regarding challenges resulting from pastoral encroachment into parks. Among the pastoralists, 74.7% migrated with their livestock for a mean 3.5 months per year, during which time, 90% of respondents reported contact with other livestock herds, and over 80% with wildlife. A third (34.2%) reported disease outbreaks in their village prior to migration. Pastoralists traveled long distances, crossing woreda, regional or national boundaries. All 58-park respondents reported pastoralists with livestock inside their park and their close contact with wildlife. Additionally, 69% reported the presence of domestic dogs. Wildlife displacement, habitat loss and dog attacks on wildlife were perceived as the main threat caused by the presence of pastoralists, whereas diseases were only mentioned by 15.5%. Overall, park staff showed poor disease knowledge. They reported poor disease surveillance and no disease response. Within pastoral contexts, improved collaboration between wildlife and livestock authorities regarding land use, disease awareness and surveillance is needed to balance the needs of both wildlife and pastoralist's livestock development and mitigate threats to wildlife habitats.
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Affiliation(s)
- Samson Abebe
- Armauer Hansen Research Institute, Jimma Road, PO Box 1005, Addis Ababa, Ethiopia
| | - Hamere Melaku
- Ethiopian Wildlife Conservation Authority, Ras Abebe Aregay Street, PO Box 386, Addis Ababa, Ethiopia
| | | | - Rea Tschopp
- Armauer Hansen Research Institute, Jimma Road, PO Box 1005, Addis Ababa, Ethiopia.
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland.
- University of Basel, Basel, Switzerland.
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Amenu K, McIntyre KM, Moje N, Knight-Jones T, Rushton J, Grace D. Approaches for disease prioritization and decision-making in animal health, 2000-2021: a structured scoping review. Front Vet Sci 2023; 10:1231711. [PMID: 37876628 PMCID: PMC10593474 DOI: 10.3389/fvets.2023.1231711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 09/06/2023] [Indexed: 10/26/2023] Open
Abstract
This scoping review identifies and describes the methods used to prioritize diseases for resource allocation across disease control, surveillance, and research and the methods used generally in decision-making on animal health policy. Three electronic databases (Medline/PubMed, Embase, and CAB Abstracts) were searched for articles from 2000 to 2021. Searches identified 6, 395 articles after de-duplication, with an additional 64 articles added manually. A total of 6, 460 articles were imported to online document review management software (sysrev.com) for screening. Based on inclusion and exclusion criteria, 532 articles passed the first screening, and after a second round of screening, 336 articles were recommended for full review. A total of 40 articles were removed after data extraction. Another 11 articles were added, having been obtained from cross-citations of already identified articles, providing a total of 307 articles to be considered in the scoping review. The results show that the main methods used for disease prioritization were based on economic analysis, multi-criteria evaluation, risk assessment, simple ranking, spatial risk mapping, and simulation modeling. Disease prioritization was performed to aid in decision-making related to various categories: (1) disease control, prevention, or eradication strategies, (2) general organizational strategy, (3) identification of high-risk areas or populations, (4) assessment of risk of disease introduction or occurrence, (5) disease surveillance, and (6) research priority setting. Of the articles included in data extraction, 50.5% had a national focus, 12.3% were local, 11.9% were regional, 6.5% were sub-national, and 3.9% were global. In 15.2% of the articles, the geographic focus was not specified. The scoping review revealed the lack of comprehensive, integrated, and mutually compatible approaches to disease prioritization and decision support tools for animal health. We recommend that future studies should focus on creating comprehensive and harmonized frameworks describing methods for disease prioritization and decision-making tools in animal health.
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Affiliation(s)
- Kebede Amenu
- Global Burden of Animal Diseases (GBADs) Programme, University of Liverpool, Liverpool, United Kingdom
- Department of Microbiology, Immunology and Veterinary, Public Health, College of Veterinary Medicine and Agriculture, Addis Ababa University, Bishoftu, Ethiopia
- Animal and Human Health Program, International Livestock Research Institute (ILRI), Addis Ababa, Ethiopia
| | - K. Marie McIntyre
- Global Burden of Animal Diseases (GBADs) Programme, University of Liverpool, Liverpool, United Kingdom
- Department of Livestock and One Health, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
- Modelling, Evidence and Policy Group, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Nebyou Moje
- Department of Biomedical Sciences, College of Veterinary Medicine and Agriculture, Addis Ababa University, Bishoftu, Ethiopia
| | - Theodore Knight-Jones
- Global Burden of Animal Diseases (GBADs) Programme, University of Liverpool, Liverpool, United Kingdom
- Animal and Human Health Program, International Livestock Research Institute (ILRI), Addis Ababa, Ethiopia
| | - Jonathan Rushton
- Global Burden of Animal Diseases (GBADs) Programme, University of Liverpool, Liverpool, United Kingdom
- Department of Livestock and One Health, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Delia Grace
- Global Burden of Animal Diseases (GBADs) Programme, University of Liverpool, Liverpool, United Kingdom
- Food and Markets Department, Natural Resources Institute, University of Greenwich, London, United Kingdom
- Animal and Human Health Program, International Livestock Research Institute (ILRI), Nairobi, Kenya
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Andriamparany JN, Heritiana JT, Haenke H, Kunz S, Schlecht E. Market supply of livestock and animal products in north-eastern Madagascar – the role of the vanilla boom. SCIENTIFIC AFRICAN 2022. [DOI: 10.1016/j.sciaf.2022.e01526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Ecological and Anthropogenic Spatial Gradients Shape Patterns of Dispersal of Foot-and-Mouth Disease Virus in Uganda. Pathogens 2022; 11:pathogens11050524. [PMID: 35631045 PMCID: PMC9143568 DOI: 10.3390/pathogens11050524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 02/04/2023] Open
Abstract
Using georeferenced phylogenetic trees, phylogeography allows researchers to elucidate interactions between environmental heterogeneities and patterns of infectious disease spread. Concordant with the increasing availability of pathogen genetic sequence data, there is a growing need for tools to test epidemiological hypotheses in this field. In this study, we apply tools traditionally used in ecology to elucidate the epidemiology of foot-and-mouth disease virus (FMDV) in Uganda. We analyze FMDV serotype O genetic sequences and their corresponding spatiotemporal metadata from a cross-sectional study of cattle. We apply step selection function (SSF) models, typically used to study wildlife habitat selection, to viral phylogenies to show that FMDV is more likely to be found in areas of low rainfall. Next, we use a novel approach, a resource gradient function (RGF) model, to elucidate characteristics of viral source and sink areas. An RGF model applied to our data reveals that areas of high cattle density and areas near livestock markets may serve as sources of FMDV dissemination in Uganda, and areas of low rainfall serve as viral sinks that experience frequent reintroductions. Our results may help to inform risk-based FMDV control strategies in Uganda. More broadly, these tools advance the phylogenetic toolkit, as they may help to uncover patterns of spread of other organisms for which genetic sequences and corresponding spatiotemporal metadata exist.
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Colenutt C, Brown E, Paton DJ, Mahapatra M, Parida S, Nelson N, Maud J, Motta P, Sumption K, Adhikari B, Kafle SC, Upadhyaya M, Pandey SK, Gubbins S. Environmental sampling for the detection of foot-and-mouth disease virus and peste des petits ruminants virus in a live goat market, Nepal. Transbound Emerg Dis 2021; 69:3041-3046. [PMID: 34331827 DOI: 10.1111/tbed.14257] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 07/20/2021] [Indexed: 01/15/2023]
Abstract
Livestock markets are considered vital parts of the agricultural economy, particularly in developing countries where livestock keeping contributes to both food security and economic stability. Animals from diverse sources are moved to markets, they mix while they are there and are subsequently redistributed over wide geographic areas. Consequently, markets provide an opportunity for targeted surveillance for circulating pathogens. This study investigated the use of environmental sampling at a live goat market in Nepal for the detection of foot-and-mouth disease virus (FMDV) and peste des petits ruminants virus (PPRV), both of which are endemic. Five visits to the market were carried out between November 2016 and April 2018, with FMDV RNA detected on four visits and PPRV RNA detected on all five visits. Overall, 4.1% of samples (nine out of 217) were positive for FMDV RNA and 60.8% (132 out of 217) were positive for PPRV RNA, though the proportion of positive samples varied amongst visits. These results demonstrate that non-invasive, environmental sampling methods have the potential to be used to detect circulation of high priority livestock diseases at a live animal market and, hence, to contribute to their surveillance and control.
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Affiliation(s)
| | - Emma Brown
- The Pirbright Institute, Pirbright, Surrey, UK
| | | | | | | | | | - Jenny Maud
- European Commission for the Control of Foot-and-Mouth Disease (EuFMD), Food and Agriculture Organization of the United Nations (FAO), Rome, Italy
| | - Paolo Motta
- European Commission for the Control of Foot-and-Mouth Disease (EuFMD), Food and Agriculture Organization of the United Nations (FAO), Rome, Italy
| | - Keith Sumption
- European Commission for the Control of Foot-and-Mouth Disease (EuFMD), Food and Agriculture Organization of the United Nations (FAO), Rome, Italy
| | - Bishnu Adhikari
- European Commission for the Control of Foot-and-Mouth Disease (EuFMD), Food and Agriculture Organization of the United Nations (FAO), Rome, Italy.,Food and Agriculture Organization of the United Nations, Nepal Country Office, Kathmandu, Nepal
| | - Sharmila Chapagain Kafle
- FMD and TADs Laboratory, Department of Livestock Services, Ministry of Livestock Development, Kathmandu, Nepal
| | - Mukul Upadhyaya
- Department of Livestock Services, Veterinary Epidemiology Centre, Ministry of Livestock Development, Kathmandu, Nepal
| | - Samjana Kafle Pandey
- Directorate of Animal Health, Department of Livestock Services, Ministry of Livestock Development, Kathmandu, Nepal
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Okello WO, MacLeod ET, Muhanguzi D, Waiswa C, Shaw AP, Welburn SC. Critical Linkages Between Livestock Production, Livestock Trade and Potential Spread of Human African Trypanosomiasis in Uganda: Bioeconomic Herd Modeling and Livestock Trade Analysis. Front Vet Sci 2021; 8:611141. [PMID: 34381829 PMCID: PMC8350160 DOI: 10.3389/fvets.2021.611141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 06/28/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Tsetse-transmitted human African trypanosomiasis (HAT) remains endemic in Uganda. The chronic form caused by Trypanosoma brucei gambiense (gHAT) is found in north-western Uganda, whereas the acute zoonotic form of the disease, caused by T. b. brucei rhodesiense (rHAT), occurs in the eastern region. Cattle is the major reservoir of rHAT in Uganda. These two forms of HAT are likely to converge resulting in a public health disaster. This study examines the intricate and intrinsic links between cattle herd dynamics, livestock trade and potential risk of spread of rHAT northwards. Methods: A bio-economic cattle herd model was developed to simulate herd dynamics at the farm level. Semi-structured interviews (n = 310), focus group discussions (n = 9) and key informant interviews (n = 9) were used to evaluate livestock markets (n = 9) as part of the cattle supply chain analysis. The cattle market data was used for stochastic risk analysis. Results: Cattle trade in eastern and northern Uganda is dominated by sale of draft and adult male cattle as well as exportation of young male cattle. The study found that the need to import draft cattle at the farm level was to cover deficits because of the herd structure, which is mostly geared towards animal traction. The importation and exportation of draft cattle and disposal of old adult male cattle formed the major basis of livestock movement and could result in the spread of rHAT northwards. The risk of rHAT infected cattle being introduced to northern Uganda from the eastern region via cattle trade was found to be high (i.e. probability of 1). Conclusion: Through deterministic and stochastic modelling of cattle herd and cattle trade dynamics, this study identifies critical links between livestock production and trade as well as potential risk of rHAT spread in eastern and northern Uganda. The findings highlight the need for targeted and routine surveillance and control of zoonotic diseases such as rHAT.
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Affiliation(s)
- Walter O Okello
- Infection Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom.,Land & Water Business Unit, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Canberra, ACT, Australia
| | - Ewan T MacLeod
- Infection Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Dennis Muhanguzi
- Department of Biomolecular and Biolaboratory Sciences, School of Biosecurity, Biotechnical and Laboratory Sciences, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Charles Waiswa
- Infection Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom.,The Coordinating Office for Control of Trypanosomiasis in Uganda (COCTU), Kampala, Uganda
| | - Alexandra P Shaw
- Infection Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom.,Avia-GIS, Zoersel, Belgium
| | - Susan C Welburn
- Infection Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom.,Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining, China
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Campbell Z, Coleman P, Guest A, Kushwaha P, Ramuthivheli T, Osebe T, Perry B, Salt J. Prioritizing smallholder animal health needs in East Africa, West Africa, and South Asia using three approaches: Literature review, expert workshops, and practitioner surveys. Prev Vet Med 2021; 189:105279. [PMID: 33581421 PMCID: PMC8024747 DOI: 10.1016/j.prevetmed.2021.105279] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 12/18/2020] [Accepted: 01/18/2021] [Indexed: 12/15/2022]
Abstract
Managing the health needs of livestock contributes to reducing poverty and improving the livelihoods of smallholder and pastoralist livestock keepers globally. Animal health practitioners, producers, policymakers, and researchers all must prioritize how to mobilize limited resources. This study employed three approaches to prioritize animal health needs in East and West Africa and South Asia to identify diseases and syndromes that impact livestock keepers. The approaches were a) systematic literature review, b) a series of expert workshops, and c) a practitioner survey of veterinarians and para-veterinary professionals. The top constraints that emerged from all three approaches include endo/ ectoparasites, foot and mouth disease, brucellosis, peste des petits ruminants, Newcastle disease, and avian influenza. Expert workshops additionally identified contagious caprine pleuropneumonia, contagious bovine pleuropneumonia, mastitis, and reproductive disorders as constraints not emphasized in the literature review. Practitioner survey results additionally identified nutrition as a constraint for smallholder dairy and pastoralist small ruminant production. Experts attending the workshops agreed most constraints can be managed using existing veterinary technologies and best husbandry practices, which supports a shift away from focusing on individual diseases and new technologies towards addressing systemic challenges that limit access to veterinary services and inputs. Few research studies focused on incidence/ prevalence of disease and impact, suggesting better incorporation of socio-economic impact measures in future research would better represent the interests of livestock keepers.
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Affiliation(s)
- Zoë Campbell
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya.
| | - Paul Coleman
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Andrea Guest
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Peetambar Kushwaha
- GALVmed Asia Office, Unit 118 & 120 B, Splendor Forum, Plot No 3, Jasola District Centre, Jasola, New Delhi, 110025, India
| | - Thembinkosi Ramuthivheli
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Tom Osebe
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Brian Perry
- Nuffield College of Clinical Medicine, University of Oxford, United Kingdom; College of Medicine and Veterinary Medicine, University of Edinburgh, Arthurstone House, Meigle, Blairgowrie, PH12 8QW, Scotland, United Kingdom
| | - Jeremy Salt
- GALVmed UK Office, Doherty Building, Pentlands Science Park, Bush Loan, Penicuik Edinburgh, EH26 0PZ, Scotland, United Kingdom
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George J, Häsler B, Komba E, Sindato C, Rweyemamu M, Mlangwa J. Towards an integrated animal health surveillance system in Tanzania: making better use of existing and potential data sources for early warning surveillance. BMC Vet Res 2021; 17:109. [PMID: 33676498 PMCID: PMC7936506 DOI: 10.1186/s12917-021-02789-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 02/03/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Effective animal health surveillance systems require reliable, high-quality, and timely data for decision making. In Tanzania, the animal health surveillance system has been relying on a few data sources, which suffer from delays in reporting, underreporting, and high cost of data collection and transmission. The integration of data from multiple sources can enhance early detection and response to animal diseases and facilitate the early control of outbreaks. This study aimed to identify and assess existing and potential data sources for the animal health surveillance system in Tanzania and how they can be better used for early warning surveillance. The study used a mixed-method design to identify and assess data sources. Data were collected through document reviews, internet search, cross-sectional survey, key informant interviews, site visits, and non-participant observation. The assessment was done using pre-defined criteria. RESULTS A total of 13 data sources were identified and assessed. Most surveillance data came from livestock farmers, slaughter facilities, and livestock markets; while animal dip sites were the least used sources. Commercial farms and veterinary shops, electronic surveillance tools like AfyaData and Event Mobile Application (EMA-i) and information systems such as the Tanzania National Livestock Identification and Traceability System (TANLITS) and Agricultural Routine Data System (ARDS) show potential to generate relevant data for the national animal health surveillance system. The common variables found across most sources were: the name of the place (12/13), animal type/species (12/13), syndromes (10/13) and number of affected animals (8/13). The majority of the sources had good surveillance data contents and were accessible with medium to maximum spatial coverage. However, there was significant variation in terms of data frequency, accuracy and cost. There were limited integration and coordination of data flow from the identified sources with minimum to non-existing automated data entry and transmission. CONCLUSION The study demonstrated how the available data sources have great potential for early warning surveillance in Tanzania. Both existing and potential data sources had complementary strengths and weaknesses; a multi-source surveillance system would be best placed to harness these different strengths.
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Affiliation(s)
- Janeth George
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, P.O. Box 3021, Morogoro, Tanzania.
- SACIDS Foundation for One Health, Sokoine University of Agriculture, P.O. Box 3297, Morogoro, Tanzania.
| | - Barbara Häsler
- Department of Pathobiology and Population Sciences, Veterinary Epidemiology, Economics, and Public Health Group, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire, AL9 7TA, UK
| | - Erick Komba
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, P.O. Box 3021, Morogoro, Tanzania
| | - Calvin Sindato
- SACIDS Foundation for One Health, Sokoine University of Agriculture, P.O. Box 3297, Morogoro, Tanzania
- National Institute for Medical Research, Tabora Research Centre, Tabora, Tanzania
| | - Mark Rweyemamu
- SACIDS Foundation for One Health, Sokoine University of Agriculture, P.O. Box 3297, Morogoro, Tanzania
| | - James Mlangwa
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, P.O. Box 3021, Morogoro, Tanzania
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Omondi GP, Obanda V, VanderWaal K, Deen J, Travis DA. Animal movement in a pastoralist population in the Maasai Mara Ecosystem in Kenya and implications for pathogen spread and control. Prev Vet Med 2021; 188:105259. [PMID: 33453561 DOI: 10.1016/j.prevetmed.2021.105259] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 12/28/2020] [Accepted: 12/31/2020] [Indexed: 12/13/2022]
Abstract
Livestock movements are important drivers for infectious disease transmission. However, paucity of such data in pastoralist communities in rangeland ecosystems limits our understanding of their dynamics and hampers disease surveillance and control. The aim of this study was to investigate animal movement networks in a pastoralist community in Kenya, and assess network-based strategies for disease control. We used network analysis to characterize five types of between-village animal movement networks. We then evaluated implications of these networks for disease spread and control by quantifying topological changes in the network associated with targeted and random removal of nodes. To construct these networks, data were collected using standardized questionnaires (N = 165 households) from communities living within the Maasai Mara Ecosystem in southwestern Kenya. Our analyses show that the Maasai Mara National Reserve (MMNR), a protected wildlife area, was critical for maintaining village connectivity in the agistment network (dry season grazing), with MMNR-adjacent villages being highly utilized during the dry season. In terms of disease dynamics, the network-based basic reproduction number, R0, was sufficient to allow disease invasion in all the five networks, and removal of villages based on degree or betweenness was not efficient in reducing R0. However, we show that villages with high degree or betweenness may play an important role in maintaining network connectivity, which may not be captured by assessment of R0 alone. Such villages may function as potential "firebreaks." For example, targeted removal of highly connected village nodes was more effective at fragmenting each network than random removal of nodes, indicating that network-based targeting of interventions such as vaccination could potentially disrupt transmission pathways in the ecosystem. In conclusion, this work shows that animal movements have the potential to shape patterns of disease transmission in this ecosystem, with targeted interventions being a practical and efficient measure for disease control.
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Affiliation(s)
- George P Omondi
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States; Ahadi Veterinary Resource Center, P.O. Box 51002, 00200, Nairobi, Kenya.
| | - Vincent Obanda
- Ahadi Veterinary Resource Center, P.O. Box 51002, 00200, Nairobi, Kenya; Veterinary Services Department, Kenya Wildlife Service, P.O. Box 40241, 00100, Nairobi, Kenya
| | - Kimberly VanderWaal
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States
| | - John Deen
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States
| | - Dominic A Travis
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States
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