A scoping review of foot‐and‐mouth disease risk, based on spatial and spatio‐temporal analysis of outbreaks in endemic settings

Abstract Foot‐and‐mouth disease (FMD) is one of the most important transboundary animal diseases affecting livestock and wildlife species worldwide. Sustained viral circulation, as evidenced by serological surveys and the recurrence of outbreaks, suggests endemic transmission cycles in some parts of Africa, Asia and the Middle East. This is the result of a complex process in which multiple serotypes, multi‐host interactions and numerous socio‐epidemiological factors converge to facilitate disease introduction, survival and spread. Spatial and spatio‐temporal analyses have been increasingly used to explore the burden of the disease by identifying high‐risk areas, analysing temporal trends and exploring the factors that contribute to the outbreaks. We systematically retrieved spatial and spatial‐temporal studies on FMD outbreaks to summarize variations on their methodological approaches and identify the epidemiological factors associated with the outbreaks in endemic contexts. Fifty‐one studies were included in the final review. A high proportion of papers described and visualized the outbreaks (72.5%) and 49.0% used one or more approaches to study their spatial, temporal and spatio‐temporal aggregation. The epidemiological aspects commonly linked to FMD risk are broadly categorizable into themes such as (a) animal demographics and interactions, (b) spatial accessibility, (c) trade, (d) socio‐economic and (e) environmental factors. The consistency of these themes across studies underlines the different pathways in which the virus is sustained in endemic areas, with the potential to exploit them to design tailored evidence based‐control programmes for the local needs. There was limited data linking the socio‐economics of communities and modelled FMD outbreaks, leaving a gap in the current knowledge. A thorough analysis of FMD outbreaks requires a systemic view as multiple epidemiological factors contribute to viral circulation and may improve the accuracy of disease mapping. Future studies should explore the links between socio‐economic and epidemiological factors as a foundation for translating the identified opportunities into interventions to improve the outcomes of FMD surveillance and control initiatives in endemic contexts.


Introduction
Rationale 3 Describe the rationale for the review in the context of what is already known. Explain why the review questions/objectives lend themselves to a scoping review approach.

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Objectives 4 Provide an explicit statement of the questions and objectives being addressed with reference to their key elements (e.g., population or participants, concepts, and context) or other relevant key elements used to conceptualize the review questions and/or objectives. 4

Protocol and registration 5
Indicate whether a review protocol exists; state if and where it can be accessed (e.g., a Web address); and if available, provide registration information, including the registration number.

Eligibility criteria 6
Specify characteristics of the sources of evidence used as eligibility criteria (e.g., years considered, language, and publication status), and provide a rationale. 4

Information sources* 7
Describe all information sources in the search (e.g., databases with dates of coverage and contact with authors to identify additional sources), as well as the date the most recent search was executed.

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Search 8 Present the full electronic search strategy for at least 1 database, including any limits used, such that it could be repeated.

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Selection of sources of evidence † 9 State the process for selecting sources of evidence (i.e., screening and eligibility) included in the scoping review.

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Data charting process ‡ 10 Describe the methods of charting data from the included sources of evidence (e.g., calibrated forms 5-6 or forms that have been tested by the team before their use, and whether data charting was done independently or in duplicate) and any processes for obtaining and confirming data from investigators.

Data items 11
List and define all variables for which data were sought and any assumptions and simplifications made.

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Critical appraisal of individual sources of evidence §

12
If done, provide a rationale for conducting a critical appraisal of included sources of evidence; describe the methods used and how this information was used in any data synthesis (if appropriate).

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Describe the methods of handling and summarizing the data that were charted. 6

Selection of sources of evidence 14
Give numbers of sources of evidence screened, assessed for eligibility, and included in the review, with reasons for exclusions at each stage, ideally using a flow diagram. 7

Characteristics of sources of evidence 15
For each source of evidence, present characteristics for which data were charted and provide the citations.

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Critical appraisal within sources of evidence

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If done, present data on critical appraisal of included sources of evidence (see item 12). NA

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For each included source of evidence, present the relevant data that were charted that relate to the review questions and objectives.

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Synthesis of results 18 Summarize and/or present the charting results as they relate to the review questions and objectives. 8-13

Summary of evidence 19
Summarize the main results (including an overview of concepts, themes, and types of evidence available), link to the review questions and objectives, and consider the relevance to key groups.

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Limitations 20 Discuss the limitations of the scoping review process. 19

Conclusions 21
Provide a general interpretation of the results with respect to the review questions and objectives, as well as potential implications and/or next steps.

Animal demographics and livestock-wildlife interactions
Explores the multispecies nature of FMDv.

Trade and commerce
Examines market-related dynamics or aspects acting as a proxy for the likelihood of economic exchange of goods and services in a location.
International border -Distance to or adjacency  "An outbreak is characterized as a cattle farm in which at least one animal displayed the typical clinical signs of FMD, including vesicles on the feet, mammary glands, and around the oral cavity" Arjkumpa, 2020 Thailand Cattle "Outbreak farms were defined as cattle farms in which at least one animals was recorded with typical clinical signs of FMD, including vesicles on the feet, mammary glands, and around the oral cavity by district livestock officers, or tissue samples (e.g. oral epithelium clinical signs and vesicle lesion tissue) from animals with typical FMD clinical signs were confirmed as being FMDV positive by PCR method, or blood samples from such animals were positive to enzymelinked immunosorbent assay technique" Ayebazibwe,