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Spatial Analysis of Mosquito-Borne Diseases in Europe: A Scoping Review. SUSTAINABILITY 2022. [DOI: 10.3390/su14158975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Mosquito-borne infections are increasing in endemic areas and previously unaffected regions. In 2020, the notification rate for Dengue was 0.5 cases per 100,000 population, and for Chikungunya <0.1/100,000. In 2019, the rate for Malaria was 1.3/100,000, and for West Nile Virus, 0.1/100,000. Spatial analysis is increasingly used in surveillance and epidemiological investigation, but reviews about their use in this research topic are scarce. We identify and describe the methodological approaches used to investigate the distribution and ecological determinants of mosquito-borne infections in Europe. Relevant literature was extracted from PubMed, Scopus, and Web of Science from inception until October 2021 and analysed according to PRISMA-ScR protocol. We identified 110 studies. Most used geographical correlation analysis (n = 50), mainly applying generalised linear models, and the remaining used spatial cluster detection (n = 30) and disease mapping (n = 30), mainly conducted using frequentist approaches. The most studied infections were Dengue (n = 32), Malaria (n = 26), Chikungunya (n = 26), and West Nile Virus (n = 24), and the most studied ecological determinants were temperature (n = 39), precipitation (n = 24), water bodies (n = 14), and vegetation (n = 11). Results from this review may support public health programs for mosquito-borne disease prevention and may help guide future research, as we recommended various good practices for spatial epidemiological studies.
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Fonseca EDS, Guimarães RB, Prestes-Carneiro LE, Tolezano JE, Rodgers MDSM, Avery RH, Malone JB. Predicted distribution of sand fly (Diptera: Psychodidae) species involved in the transmission of Leishmaniasis in São Paulo state, Brazil, utilizing maximum entropy ecological niche modeling. Pathog Glob Health 2021; 115:108-120. [PMID: 33427124 PMCID: PMC8550198 DOI: 10.1080/20477724.2020.1870031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Leishmaniasis is a public health problem worldwide. We aimed to predict ecological niche models (ENMs) for visceral (VL) and cutaneous (CL) leishmaniasis and the sand flies involved in the transmission of leishmaniasis in São Paulo, Brazil. Phlebotomine sand flies were collected between 1985 and 2015. ENMs were created for each sand fly species using Maximum Entropy Species Distribution Modeling software, and 20 climatic variables were determined. Nyssomyia intermedia (Lutz & Neiva, 1912) and Lutzomyia longipalpis (Lutz & Neiva, 1912), the primary vectors involved in CL and VL, displayed the highest suitability across the various regions, climates, and topographies. L. longipalpis was found in the border of Paraná an area currently free of VL. The variables with the greatest impact were temperature seasonality, precipitation, and altitude. Co-presence of multiple sand fly species was observed in the cuestas and coastal areas along the border of Paraná and in the western basalt areas along the border of Mato Grosso do Sul. Human CL and VL were found in 475 of 546 (86.7%) and 106 of 645 (16.4%) of municipalities, respectively. Niche overlap between N. intermedia and L. longipalpis was found with 9208 human cases of CL and 2952 cases of VL. ENMs demonstrated that each phlebotomine sand fly species has a unique geographic distribution pattern, and the occurrence of the primary vectors of CL and VL overlapped. These data can be used by public authorities to monitor the dispersion and expansion of CL and VL vectors in São Paulo state.
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Affiliation(s)
| | - Raul Borges Guimarães
- Geography Department, Faculty of Science and Technology, Paulista State University Julio De Mesquita Filho, Presidente Prudente, SP, Brazil
| | | | - José Eduardo Tolezano
- Center for Parasitology and Mycology, Systemic Parasitic Nucleus, Instituto Adolfo Lutz, São Paulo, SP, Brazil
| | | | - Ryan Harry Avery
- Department of Pathobiological Sciences, School of Veterinary Medicine, Baton Rouge, LA, USA
| | - John B. Malone
- Department of Pathobiological Sciences, School of Veterinary Medicine, Baton Rouge, LA, USA
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Fischer L, Gültekin N, Kaelin MB, Fehr J, Schlagenhauf P. Rising temperature and its impact on receptivity to malaria transmission in Europe: A systematic review. Travel Med Infect Dis 2020; 36:101815. [PMID: 32629138 DOI: 10.1016/j.tmaid.2020.101815] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 11/25/2022]
Abstract
BACKGROUND Malaria is one of the most life-threatening vector-borne diseases globally. Recent autochthonous cases registered in several European countries have raised awareness regarding the threat of malaria reintroduction to Europe. An increasing number of imported malaria cases today occur due to international travel and migrant flows from malaria-endemic countries. The cumulative factors of the presence of competent vectors, favourable climatic conditions and evidence of increasing temperatures might lead to the re-emergence of malaria in countries where the infection was previously eliminated. METHODS We performed a systematic literature review following PRISMA guidelines. We searched for original articles focusing on rising temperature and the receptivity to malaria transmission in Europe. We evaluated the quality of the selected studies using a standardised tool. RESULTS The search resulted in 1'999 articles of possible relevance and after screening we included 10 original research papers in the quantitative analysis for the systematic review. With further increasing temperatures studies predicted a northward spread of the occurrence of Anopheles mosquitoes and an extension of seasonality, enabling malaria transmission for annual periods up to 6 months in the years 2051-2080. Highest vector stability and receptivity were predicted in Southern and South-Eastern European areas. Anopheles atroparvus, the main potential malaria vector in Europe, might play an important role under changing conditions favouring malaria transmission. CONCLUSION The receptivity of Europe for malaria transmission will increase as a result of rising temperature unless socioeconomic factors remain favourable and appropriate public health measures are implemented. Our systematic review serves as an evidence base for future preventive measures.
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Affiliation(s)
- Lena Fischer
- Department of Public and Global Health, MilMedBiol Competence Centre, Institute for Epidemiology, Biostatistics and Prevention, University of Zurich, Zurich, Switzerland
| | - Nejla Gültekin
- Centre of Competence for Military and Disaster Medicine, Federal Department of Defence, Civil Protection and Sport DDPS, Swiss Armed Forces, Switzerland
| | - Marisa B Kaelin
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich & Department of Public and Global Health, Institute for Epidemiology, Biostatistics and Prevention, University of Zurich, Zurich, Switzerland
| | - Jan Fehr
- University of Zurich Centre for Travel Medicine, WHO Collaborating Centre for Travellers' Health, Department of Public and Global Health, Institute for Epidemiology, Biostatistics and Prevention, Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Patricia Schlagenhauf
- University of Zurich Centre for Travel Medicine, WHO Collaborating Centre for Travellers' Health, Department of Public and Global Health, MilMedBiol Competence Centre, Institute for Epidemiology, Biostatistics and Prevention, University of Zurich, Zurich, Switzerland.
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Hertig E. Distribution of Anopheles vectors and potential malaria transmission stability in Europe and the Mediterranean area under future climate change. Parasit Vectors 2019; 12:18. [PMID: 30621785 PMCID: PMC6325871 DOI: 10.1186/s13071-018-3278-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 12/21/2018] [Indexed: 11/24/2022] Open
Abstract
Background In the scope of climate change the possible recurrence and/or expansion of vector-borne diseases poses a major concern. The occurrence of vector competent Anopheles species as well as favorable climatic conditions may lead to the re-emergence of autochthonous malaria in Europe and the Mediterranean area. However, high-resolution assessments of possible changes of Anopheles vector distributions and of potential malaria transmission stability in the European-Mediterranean area under changing climatic conditions during the course of the 21st century are not available yet. Methods Boosted Regression Trees are applied to relate climate variables and land cover classes to vector occurrences. Changes in future vector distributions and potential malaria transmission stability due to climate change are assessed using state-of-the art regional climate model simulations. Results Distinct changes in the distributions of the dominant vectors of human malaria are to be expected under climate change. In general, temperature and precipitation changes will lead to a northward spread of the occurrences of Anopheles vectors. Yet, for some Mediterranean areas, occurrence probabilities may decline. Conclusions Potential malaria transmission stability is increased in areas where the climatic changes favor vector occurrences as well as significantly impact the vectorial capacity. As a result, vector stability shows the highest increases between historical and future periods for the southern and south-eastern European areas. Anopheles atroparvus, the dominant vector in large parts of Europe, might play an important role with respect to changes of the potential transmission stability. Electronic supplementary material The online version of this article (10.1186/s13071-018-3278-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elke Hertig
- Institute of Geography, University of Augsburg, Alter Postweg 118, 86135, Augsburg, Germany.
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McIntyre KM, Setzkorn C, Hepworth PJ, Morand S, Morse AP, Baylis M. Systematic Assessment of the Climate Sensitivity of Important Human and Domestic Animals Pathogens in Europe. Sci Rep 2017; 7:7134. [PMID: 28769039 PMCID: PMC5541049 DOI: 10.1038/s41598-017-06948-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 06/19/2017] [Indexed: 12/05/2022] Open
Abstract
Climate change is expected to threaten human health and well-being via its effects on climate-sensitive infectious diseases, potentially changing their spatial distributions, affecting annual/seasonal cycles, or altering disease incidence and severity. Climate sensitivity of pathogens is a key indicator that diseases might respond to climate change, but the proportion of pathogens that is climate-sensitive, and their characteristics, are not known. The climate sensitivity of European human and domestic animal infectious pathogens, and the characteristics associated with sensitivity, were assessed systematically in terms of selection of pathogens and choice of literature reviewed. Sixty-three percent (N = 157) of pathogens were climate sensitive; 82% to primary drivers such as rainfall and temperature. Protozoa and helminths, vector-borne, foodborne, soilborne and waterborne transmission routes were associated with larger numbers of climate drivers. Zoonotic pathogens were more climate sensitive than human- or animal-only pathogens. Thirty-seven percent of disability-adjusted-life-years arise from human infectious diseases that are sensitive to primary climate drivers. These results help prioritize surveillance for pathogens that may respond to climate change. Although this study identifies a high degree of climate sensitivity among important pathogens, their response to climate change will be dependent on the nature of their association with climate drivers and impacts of other drivers.
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Affiliation(s)
- K Marie McIntyre
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, Cheshire, CH64 7TE, UK. .,NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, Liverpool, L69 7BE, UK.
| | - Christian Setzkorn
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, Cheshire, CH64 7TE, UK
| | - Philip J Hepworth
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, Cheshire, CH64 7TE, UK
| | - Serge Morand
- CNRS ISEM - CIRAD ASTRE, Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand.,Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Andrew P Morse
- NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, Liverpool, L69 7BE, UK.,Department of Geography and Planning, School of Environmental Sciences, Roxby Building, University of Liverpool, Liverpool, L69 7ZT, UK
| | - Matthew Baylis
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, Cheshire, CH64 7TE, UK. .,NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, Liverpool, L69 7BE, UK.
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Cegolon L, Heymann WC, Lange JH. Climate change, emerging infections and blood donations. J Travel Med 2017; 24:3066370. [PMID: 28355622 DOI: 10.1093/jtm/taw098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/17/2016] [Indexed: 11/13/2022]
Affiliation(s)
- L Cegolon
- IRCCS Burlo Garofolo, Scientific Directorate, Trieste, Italy
| | - W C Heymann
- Florida Department of Health, Sarasota County Health Department, Sarasota, FL, USA
| | - J H Lange
- Envirosafe Training and Consultants, 2366 Golden Mile Highway, PMB 111, Pittsburgh, PA, USA
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Abdul-Ghani R, Farag HF, Allam AF, Azazy AA. Measuring resistant-genotype transmission of malaria parasites: challenges and prospects. Parasitol Res 2014; 113:1481-7. [PMID: 24562760 DOI: 10.1007/s00436-014-3789-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Accepted: 01/28/2014] [Indexed: 01/09/2023]
Abstract
Increased gametocytemia in infections with resistant strains of Plasmodium species and their enhanced transmissibility are a matter of concern in planning and evaluating the impact of malaria control strategies. Various studies have determined weekly gametocyte carriage in response to antimalarial drugs in clinical trials. The advent of molecular biology techniques makes it easy to detect and quantify gametocytes, the stages responsible for transmission, and to detect resistant genotypes of the parasite. With the validation of molecular markers of resistance to certain antimalarial drugs, there is a need to devise a simpler formula that could be used with these epidemiological antimalarial resistance tools. Theoretical models for transmission of resistant malaria parasites are difficult to deploy in epidemiological studies. Therefore, devising a simple formula that determines the potential resistant-genotype transmission of malaria parasites should provide further insights into understanding the spread of drug resistance. The present perspective discusses gametocytogenesis in the context of antimalarial treatment and drug resistance. It also highlights the difficulties in applying the available theoretical models of drug resistance transmission and suggests Rashad's devised formula that could perhaps be used in determining potentially transmissible resistant genotypes as well as in mapping areas with high potential risk for the transmission of drug-resistant malaria. The suggested formula makes use of the data on gametocytes and resistant genotypes of malaria parasites, detected by molecular techniques in a certain geographical area within a particular point in time, to calculate the potential risk of resistant genotype transmission.
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Affiliation(s)
- Rashad Abdul-Ghani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen,
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Current situation of Leishmania infantum infection in shelter dogs in northern Spain. Parasit Vectors 2012; 5:60. [PMID: 22452948 PMCID: PMC3348073 DOI: 10.1186/1756-3305-5-60] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 03/27/2012] [Indexed: 11/22/2022] Open
Abstract
Background Canine leishmaniosis (CanL) caused by Leishmania infantum is a widespread endemic disease in the Mediterranean basin, though, so far, the north of Spain has been considered a non-endemic area. The aim of the present study was to determine the prevalence of specific antibodies to L. infantum among stray dogs living in shelters in this area, and to evaluate the clinical status (both clinical signs and clinico-pathological abnormalities) of seropositive dogs. Besides L. infantum infection, the epidemiological role of variables like sex, breed and age was also assessed. Methods Over the year 2011 a cross-sectional study was conducted on a total of 418 stray dogs. A preliminary entomological survey was carried out using CDC-light traps. The chi-squared test was used to examine relationships between L. infantum seroprevalence and the remaining variables. Results The overall seroprevalence of L. infantum infection detected was 3% in the Cantabrian coast. In Orense the seroprevalence was 35.6%. In this latter region, the presence of sand fly, Phlebotomus perniciosus was also detected. In general, seropositivity for L. infantum was related to size (large breed dogs versus small) and age, with a significantly higher seroprevalence recorded in younger (0-3 years) and older dogs (> 7 years) than adult dogs. Clinical signs of CanL were observed in 41.3% of the seropositive dogs. The seropositivity for L. infantum infection associated with the presence of clinical signs and/or abnormal laboratory findings shows a prevalence of 4.5%. Conclusion Our data provide new insight into the prevalence of CanL across northern Spain. The situation observed in Orense seems to be worsening compared to the few reports available, with figures being similar to those cited for known endemic areas of Spain. Besides, the presence of P. perniciosus in Orense points out to a risk of the spread of this zoonotic disease in this geographical area. These findings identify a need for an active search for the sand fly vectors of L. infantum across the entire northern spanish region including the rest of Galicia, Asturias, Cantabria and the Basque Country.
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Lourenço PM, Sousa CA, Seixas J, Lopes P, Novo MT, Almeida APG. Anopheles atroparvus density modeling using MODIS NDVI in a former malarious area in Portugal. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2011; 36:279-291. [PMID: 22129399 DOI: 10.1111/j.1948-7134.2011.00168.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Malaria is dependent on environmental factors and considered as potentially re-emerging in temperate regions. Remote sensing data have been used successfully for monitoring environmental conditions that influence the patterns of such arthropod vector-borne diseases. Anopheles atroparvus density data were collected from 2002 to 2005, on a bimonthly basis, at three sites in a former malarial area in Southern Portugal. The development of the Remote Vector Model (RVM) was based upon two main variables: temperature and the Normalized Differential Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra satellite. Temperature influences the mosquito life cycle and affects its intra-annual prevalence, and MODIS NDVI was used as a proxy for suitable habitat conditions. Mosquito data were used for calibration and validation of the model. For areas with high mosquito density, the model validation demonstrated a Pearson correlation of 0.68 (p<0.05) and a modelling efficiency/Nash-Sutcliffe of 0.44 representing the model's ability to predict intra- and inter-annual vector density trends. RVM estimates the density of the former malarial vector An. atroparvus as a function of temperature and of MODIS NDVI. RVM is a satellite data-based assimilation algorithm that uses temperature fields to predict the intra- and inter-annual densities of this mosquito species using MODIS NDVI. RVM is a relevant tool for vector density estimation, contributing to the risk assessment of transmission of mosquito-borne diseases and can be part of the early warning system and contingency plans providing support to the decision making process of relevant authorities.
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Affiliation(s)
- Pedro M Lourenço
- Departmento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus da Caparica 2829-516 Monte de Caparica, Portugal
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Integrated mapping of establishment risk for emerging vector-borne infections: a case study of canine leishmaniasis in southwest France. PLoS One 2011; 6:e20817. [PMID: 21857899 PMCID: PMC3153454 DOI: 10.1371/journal.pone.0020817] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Accepted: 05/13/2011] [Indexed: 11/23/2022] Open
Abstract
Background Zoonotic visceral leishmaniasis is endemic in the Mediterranean Basin, where the dog is the main reservoir host. The disease's causative agent, Leishmania infantum, is transmitted by blood-feeding female sandflies. This paper reports an integrative study of canine leishmaniasis in a region of France spanning the southwest Massif Central and the northeast Pyrenees, where the vectors are the sandflies Phlebotomus ariasi and P. perniciosus. Methods Sandflies were sampled in 2005 using sticky traps placed uniformly over an area of approximately 100 by 150 km. High- and low-resolution satellite data for the area were combined to construct a model of the sandfly data, which was then used to predict sandfly abundance throughout the area on a pixel by pixel basis (resolution of c. 1 km). Using literature- and expert-derived estimates of other variables and parameters, a spatially explicit R0 map for leishmaniasis was constructed within a Geographical Information System. R0 is a measure of the risk of establishment of a disease in an area, and it also correlates with the amount of control needed to stop transmission. Conclusions To our knowledge, this is the first analysis that combines a vector abundance prediction model, based on remotely-sensed variables measured at different levels of spatial resolution, with a fully mechanistic process-based temperature-dependent R0 model. The resulting maps should be considered as proofs-of-principle rather than as ready-to-use risk maps, since validation is currently not possible. The described approach, based on integrating several modeling methods, provides a useful new set of tools for the study of the risk of outbreaks of vector-borne diseases.
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Sainz-Elipe S, Latorre JM, Escosa R, Masià M, Fuentes MV, Mas-Coma S, Bargues MD. Malaria resurgence risk in southern Europe: climate assessment in an historically endemic area of rice fields at the Mediterranean shore of Spain. Malar J 2010; 9:221. [PMID: 20673367 PMCID: PMC2924348 DOI: 10.1186/1475-2875-9-221] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2010] [Accepted: 07/31/2010] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND International travel and immigration have been related with an increase of imported malaria cases. This fact and climate change, prolonging the period favouring vector development, require an analysis of the malaria transmission resurgence risk in areas of southern Europe. Such a study is made for the first time in Spain. The Ebro Delta historically endemic area was selected due to its rice field landscape, the presence of only one vector, Anopheles atroparvus, with densities similar to those it presented when malaria was present, in a situation which pronouncedly differs from already assessed potential resurgence areas in other Mediterranean countries, such as France and Italy, where many different Anopheles species coexist and a different vector species dominates. METHODS The transmission risk was assessed analysing: 1) climate diagrams including the minimum temperature for Plasmodium falciparum and Plasmodium vivax development; 2) monthly evolution of the Gradient Model Risk (GMR) index, specifying transmission risk period and number of potential Plasmodium generations; 3) ecological characteristics using remote sensing images with the Eurasia Land Cover characteristics database and the monthly evolution of the Normalized Difference Vegetation Index (NDVI); 4) evaluation of A. atroparvus population dynamics. RESULTS Climatological analyses and GMR index show that a transmission risk presently exists, lasting from May until September for P. falciparum, and from May until October for P. vivax. The GMR index shows that the temperature increase does not actually mean a transmission risk increase if accompanied by a precipitation decrease reducing the number of parasite generations and transmission period. Nevertheless, this limitation is offset by the artificial flooding of the rice fields. Maximum NDVI values and A. atroparvus maximum abundance correspond to months with maximum growth of the rice fields. CONCLUSIONS The Ebro Delta presents the ecological characteristics that favour transmission. The temperature increase has favoured a widening of the monthly potential transmission window with respect to when malaria was endemic. The combined application of modified climate diagrams and GMR index, together with spatial characterization conforms a useful tool for assessing potential areas at risk of malaria resurgence. NDVI is a good marker when dealing with a rice field area.
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Affiliation(s)
- Sandra Sainz-Elipe
- Departamento de Parasitología, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
| | - Jose Manuel Latorre
- Departamento de Parasitología, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
| | - Raul Escosa
- Consorci de Serveis Agroambientals de les Comarques del Baix Ebre i Montsia (CODE), Av. I. Soriano-Montagut 86, 43870 Amposta, Tarragona, Spain
| | - Montserrat Masià
- Consorci de Serveis Agroambientals de les Comarques del Baix Ebre i Montsia (CODE), Av. I. Soriano-Montagut 86, 43870 Amposta, Tarragona, Spain
| | - Marius Vicent Fuentes
- Departamento de Parasitología, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
| | - Santiago Mas-Coma
- Departamento de Parasitología, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
| | - Maria Dolores Bargues
- Departamento de Parasitología, Facultad de Farmacia, Universidad de Valencia, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
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Lindsay SW, Hole DG, Hutchinson RA, Richards SA, Willis SG. Assessing the future threat from vivax malaria in the United Kingdom using two markedly different modelling approaches. Malar J 2010; 9:70. [PMID: 20205713 PMCID: PMC2845590 DOI: 10.1186/1475-2875-9-70] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2009] [Accepted: 03/05/2010] [Indexed: 04/28/2023] Open
Abstract
Background The world is facing an increased threat from new and emerging diseases, and there is concern that climate change will expand areas suitable for transmission of vector borne diseases. The likelihood of vivax malaria returning to the UK was explored using two markedly different modelling approaches. First, a simple temperature-dependent, process-based model of malaria growth transmitted by Anopheles atroparvus, the historical vector of malaria in the UK. Second, a statistical model using logistic-regression was used to predict historical malaria incidence between 1917 and 1918 in the UK, based on environmental and demographic data. Using findings from these models and saltmarsh distributions, future risk maps for malaria in the UK were produced based on UKCIP02 climate change scenarios. Results The process-based model of climate suitability showed good correspondence with historical records of malaria cases. An analysis of the statistical models showed that mean temperature of the warmest month of the year was the major factor explaining the distribution of malaria, further supporting the use of the temperature-driven processed-based model. The risk maps indicate that large areas of central and southern England could support malaria transmission today and could increase in extent in the future. Confidence in these predictions is increased by the concordance between the processed-based and statistical models. Conclusion Although the future climate in the UK is favourable for the transmission of vivax malaria, the future risk of locally transmitted malaria is considered low because of low vector biting rates and the low probability of vectors feeding on a malaria-infected person.
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Affiliation(s)
- Steven W Lindsay
- Disease Control and Vector Biology Unit, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
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