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Pathogenic landscapes: interactions between land, people, disease vectors, and their animal hosts.

Lambin EF, Tran A, Vanwambeke SO, Linard C, Soti V - Int J Health Geogr (2010)

Bottom Line: We formulated ten propositions that are related to landscape attributes, spatial patterns and habitat connectivity, pathways of pathogen transmission between vectors and hosts, scale issues, land use and ownership, and human behaviour associated with transmission cycles.We also highlight the complementarity of the modelling approaches used in our case studies.Integrated analyses at the landscape scale allows a better understanding of interactions between changes in ecosystems and climate, land use and human behaviour, and the ecology of vectors and animal hosts of infectious agents.

View Article: PubMed Central - HTML - PubMed

Affiliation: Georges LemaƮtre Centre for Earth and Climate Research, Earth and Life Institute, University of Louvain, 3 place Pasteur, Louvain-la-Neuve, B-1348, Belgium. eric.lambin@uclouvain.be

ABSTRACT

Background: Landscape attributes influence spatial variations in disease risk or incidence. We present a review of the key findings from eight case studies that we conducted in Europe and West Africa on the impact of land changes on emerging or re-emerging vector-borne diseases and/or zoonoses. The case studies concern West Nile virus transmission in Senegal, tick-borne encephalitis incidence in Latvia, sandfly abundance in the French Pyrenees, Rift Valley Fever in the Ferlo (Senegal), West Nile Fever and the risk of malaria re-emergence in the Camargue, and rodent-borne Puumala hantavirus and Lyme borreliosis in Belgium.

Results: We identified general principles governing landscape epidemiology in these diverse disease systems and geographic regions. We formulated ten propositions that are related to landscape attributes, spatial patterns and habitat connectivity, pathways of pathogen transmission between vectors and hosts, scale issues, land use and ownership, and human behaviour associated with transmission cycles.

Conclusions: A static view of the "pathogenecity" of landscapes overlays maps of the spatial distribution of vectors and their habitats, animal hosts carrying specific pathogens and their habitat, and susceptible human hosts and their land use. A more dynamic view emphasizing the spatial and temporal interactions between these agents at multiple scales is more appropriate. We also highlight the complementarity of the modelling approaches used in our case studies. Integrated analyses at the landscape scale allows a better understanding of interactions between changes in ecosystems and climate, land use and human behaviour, and the ecology of vectors and animal hosts of infectious agents.

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Related in: MedlinePlus

Larval index map for the mosquito Anopheles hyrcanus derived from a statistical model associating entomological field data with satellite imagery in the Camargue, France.
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Figure 1: Larval index map for the mosquito Anopheles hyrcanus derived from a statistical model associating entomological field data with satellite imagery in the Camargue, France.

Mentions: A larval index for the main potential vector of malaria in the Camargue area, Anopheles hyrcanus, was defined as the probability of observing its larvae in a given site at least once over a year. It was mapped by associating in a statistical model environmental indices that were derived from high spatial resolution imagery and entomological field data (Figure 1) [26]. Linard et al. [14] developed a spatially-explicit multi-agent simulation representing the spatio-temporal dynamics of interactions between the agents that could influence malaria transmission in the Camargue: people, mosquitoes, animal hosts and landscape. This model integrates movements and behaviours of people and vectors, and factors influencing transmission risk spatially. The model allowed testing potential drivers of malaria re-emergence such as changes in biological attributes of vectors, agricultural practices, land use, tourism activities and climate. Scenarios of possible futures varied the value of exogenous variables (e.g., tourist population visiting the area), initial conditions (e.g., land cover, in response to changes in land use policies or market forces) or parameters (e.g., level of protection of visitors against mosquito bites) [27].


Pathogenic landscapes: interactions between land, people, disease vectors, and their animal hosts.

Lambin EF, Tran A, Vanwambeke SO, Linard C, Soti V - Int J Health Geogr (2010)

Larval index map for the mosquito Anopheles hyrcanus derived from a statistical model associating entomological field data with satellite imagery in the Camargue, France.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2984574&req=5

Figure 1: Larval index map for the mosquito Anopheles hyrcanus derived from a statistical model associating entomological field data with satellite imagery in the Camargue, France.
Mentions: A larval index for the main potential vector of malaria in the Camargue area, Anopheles hyrcanus, was defined as the probability of observing its larvae in a given site at least once over a year. It was mapped by associating in a statistical model environmental indices that were derived from high spatial resolution imagery and entomological field data (Figure 1) [26]. Linard et al. [14] developed a spatially-explicit multi-agent simulation representing the spatio-temporal dynamics of interactions between the agents that could influence malaria transmission in the Camargue: people, mosquitoes, animal hosts and landscape. This model integrates movements and behaviours of people and vectors, and factors influencing transmission risk spatially. The model allowed testing potential drivers of malaria re-emergence such as changes in biological attributes of vectors, agricultural practices, land use, tourism activities and climate. Scenarios of possible futures varied the value of exogenous variables (e.g., tourist population visiting the area), initial conditions (e.g., land cover, in response to changes in land use policies or market forces) or parameters (e.g., level of protection of visitors against mosquito bites) [27].

Bottom Line: We formulated ten propositions that are related to landscape attributes, spatial patterns and habitat connectivity, pathways of pathogen transmission between vectors and hosts, scale issues, land use and ownership, and human behaviour associated with transmission cycles.We also highlight the complementarity of the modelling approaches used in our case studies.Integrated analyses at the landscape scale allows a better understanding of interactions between changes in ecosystems and climate, land use and human behaviour, and the ecology of vectors and animal hosts of infectious agents.

View Article: PubMed Central - HTML - PubMed

Affiliation: Georges LemaƮtre Centre for Earth and Climate Research, Earth and Life Institute, University of Louvain, 3 place Pasteur, Louvain-la-Neuve, B-1348, Belgium. eric.lambin@uclouvain.be

ABSTRACT

Background: Landscape attributes influence spatial variations in disease risk or incidence. We present a review of the key findings from eight case studies that we conducted in Europe and West Africa on the impact of land changes on emerging or re-emerging vector-borne diseases and/or zoonoses. The case studies concern West Nile virus transmission in Senegal, tick-borne encephalitis incidence in Latvia, sandfly abundance in the French Pyrenees, Rift Valley Fever in the Ferlo (Senegal), West Nile Fever and the risk of malaria re-emergence in the Camargue, and rodent-borne Puumala hantavirus and Lyme borreliosis in Belgium.

Results: We identified general principles governing landscape epidemiology in these diverse disease systems and geographic regions. We formulated ten propositions that are related to landscape attributes, spatial patterns and habitat connectivity, pathways of pathogen transmission between vectors and hosts, scale issues, land use and ownership, and human behaviour associated with transmission cycles.

Conclusions: A static view of the "pathogenecity" of landscapes overlays maps of the spatial distribution of vectors and their habitats, animal hosts carrying specific pathogens and their habitat, and susceptible human hosts and their land use. A more dynamic view emphasizing the spatial and temporal interactions between these agents at multiple scales is more appropriate. We also highlight the complementarity of the modelling approaches used in our case studies. Integrated analyses at the landscape scale allows a better understanding of interactions between changes in ecosystems and climate, land use and human behaviour, and the ecology of vectors and animal hosts of infectious agents.

Show MeSH
Related in: MedlinePlus