TY - JOUR
T1 - Modelling the global constraints of temperature on transmission of Plasmodium falciparum and P. vivax
AU - Gething, Peter W.
AU - Van Boeckel, Thomas P.
AU - Smith, David L.
AU - Guerra, Carlos A.
AU - Patil, Anand P.
AU - Snow, Robert W.
AU - Hay, Simon I.
N1 - Funding Information:
We thank Anja Bibby and Katherine Battle for proof reading this manuscript. SIH is funded by a Senior Research Fellowship from the Wellcome Trust (#079091), which also supports CAG and PWG. DLS is supported by a grant from the Bill and Melinda Gates Foundation (#49446). DLS and SIH also acknowledge funding support from the RAPIDD program of the Science & Technology Directorate, Department of Homeland Security, and the Fogarty International Center, National Institutes of Health. RWS is funded by a Wellcome Trust Principal Research Fellowship (#079080), which also supports APP. TPVB is funded by a grant from the Belgian Fond National pour la Recherche Scientifique and the Fondation Wiener-Anspach. The authors acknowledge the support of the Kenyan Medical Research Institute (KEMRI) and this paper is published with the permission of the director of KEMRI. This work forms part of the output of the Malaria Atlas Project (MAP, http:// www.map.ox.ac.uk), principally funded by the Wellcome Trust, UK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
PY - 2011
Y1 - 2011
N2 - Abstract. Background: Temperature is a key determinant of environmental suitability for transmission of human malaria, modulating endemicity in some regions and preventing transmission in others. The spatial modelling of malaria endemicity has become increasingly sophisticated and is now central to the global scale planning, implementation, and monitoring of disease control and regional efforts towards elimination, but existing efforts to model the constraints of temperature on the malaria landscape at these scales have been simplistic. Here, we define an analytical framework to model these constraints appropriately at fine spatial and temporal resolutions, providing a detailed dynamic description that can enhance large scale malaria cartography as a decision-support tool in public health. Results: We defined a dynamic biological model that incorporated the principal mechanisms of temperature dependency in the malaria transmission cycle and used it with fine spatial and temporal resolution temperature data to evaluate time-series of temperature suitability for transmission of Plasmodium falciparum and P. vivax throughout an average year, quantified using an index proportional to the basic reproductive number. Time-series were calculated for all 1 km resolution land pixels globally and were summarised to create high-resolution maps for each species delineating those regions where temperature precludes transmission throughout the year. Within suitable zones we mapped for each pixel the number of days in which transmission is possible and an integrated measure of the intensity of suitability across the year. The detailed evaluation of temporal suitability dynamics provided by the model is visualised in a series of accompanying animations. Conclusions: These modelled products, made available freely in the public domain, can support the refined delineation of populations at risk; enhance endemicity mapping by offering a detailed, dynamic, and biologically driven alternative to the ubiquitous empirical incorporation of raw temperature data in geospatial models; and provide a rich spatial and temporal platform for future biological modelling studies.
AB - Abstract. Background: Temperature is a key determinant of environmental suitability for transmission of human malaria, modulating endemicity in some regions and preventing transmission in others. The spatial modelling of malaria endemicity has become increasingly sophisticated and is now central to the global scale planning, implementation, and monitoring of disease control and regional efforts towards elimination, but existing efforts to model the constraints of temperature on the malaria landscape at these scales have been simplistic. Here, we define an analytical framework to model these constraints appropriately at fine spatial and temporal resolutions, providing a detailed dynamic description that can enhance large scale malaria cartography as a decision-support tool in public health. Results: We defined a dynamic biological model that incorporated the principal mechanisms of temperature dependency in the malaria transmission cycle and used it with fine spatial and temporal resolution temperature data to evaluate time-series of temperature suitability for transmission of Plasmodium falciparum and P. vivax throughout an average year, quantified using an index proportional to the basic reproductive number. Time-series were calculated for all 1 km resolution land pixels globally and were summarised to create high-resolution maps for each species delineating those regions where temperature precludes transmission throughout the year. Within suitable zones we mapped for each pixel the number of days in which transmission is possible and an integrated measure of the intensity of suitability across the year. The detailed evaluation of temporal suitability dynamics provided by the model is visualised in a series of accompanying animations. Conclusions: These modelled products, made available freely in the public domain, can support the refined delineation of populations at risk; enhance endemicity mapping by offering a detailed, dynamic, and biologically driven alternative to the ubiquitous empirical incorporation of raw temperature data in geospatial models; and provide a rich spatial and temporal platform for future biological modelling studies.
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U2 - 10.1186/1756-3305-4-92
DO - 10.1186/1756-3305-4-92
M3 - Article
C2 - 21615906
AN - SCOPUS:79957528416
SN - 1756-3305
VL - 4
JO - Parasites and Vectors
JF - Parasites and Vectors
IS - 1
M1 - 92
ER -