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ABSTRACT
Temperature and climate change influence the transmission and life cycle of malaria. The regions of central and western Africa are locations where malaria is a severe public health problem. Published work has reviewed components of malaria, but there remains an incomplete analysis of the severity of future climate change on malaria. This literature review examined key research questions analyzing effected geographical locations of malaria, factors contributing to climate change, current and future prevention methods and relevant research and gaps in research services and policy. Primary academic literature was reviewed and chosen based on specific inclusion and exclusion criteria. The results show an analysis of these research questions and indicate an emphasis on research. Important findings found that advanced technology needs to become a main factor in funding for prevention programs. Global education methods for health professionals and the community need to become a priority to decrease the impact of climate on disease. In addition, humans need to have a better understanding of how their actions impact the earths climate and individual health. The public health importance of this review is critical not only to African Regions, but for global health as a whole. It is a valuable educational tool that highlights the need for additional research in the areas of climate change and vector response, environmental influences, prevention, policy, and contributes to the public health issue of malaria in the fight for Central and Western African health.
TABLE OF CONTENTS
TOC \o "2-4" \h \z \t "Heading 1,1,Appendix,1,Heading,1" HYPERLINK \l "_Toc355351137" preface PAGEREF _Toc355351137 \h viii
HYPERLINK \l "_Toc355351138" 1.0 Introduction PAGEREF _Toc355351138 \h 1
HYPERLINK \l "_Toc355351139" 1.1 Methods PAGEREF _Toc355351139 \h 5
HYPERLINK \l "_Toc355351140" 1.1.1 Problem Statement PAGEREF _Toc355351140 \h 6
HYPERLINK \l "_Toc355351141" 1.1.2 Research Questions PAGEREF _Toc355351141 \h 7
HYPERLINK \l "_Toc355351142" 2.0 findings/results PAGEREF _Toc355351142 \h 8
HYPERLINK \l "_Toc355351143" 2.1 What areas in the world are most affected by climate change and increase incidence of malaria? PAGEREF _Toc355351143 \h 8
HYPERLINK \l "_Toc355351144" 2.2 how do enviromental factors contribute to climate change? PAGEREF _Toc355351144 \h 12
HYPERLINK \l "_Toc355351145" 2.3 how do public health measures and related research contribute to the current and future prevention and control of malaria? PAGEREF _Toc355351145 \h 14
HYPERLINK \l "_Toc355351146" 2.4 what gaps in research and policy are needed for the future? PAGEREF _Toc355351146 \h 17
HYPERLINK \l "_Toc355351147" 3.0 Implications for public health PAGEREF _Toc355351147 \h 19
HYPERLINK \l "_Toc355351148" 3.1 Research PAGEREF _Toc355351148 \h 19
HYPERLINK \l "_Toc355351149" 3.2 Policy PAGEREF _Toc355351149 \h 19
HYPERLINK \l "_Toc355351150" 3.3 Public Education PAGEREF _Toc355351150 \h 20
HYPERLINK \l "_Toc355351151" 3.4 Health professional education PAGEREF _Toc355351151 \h 20
HYPERLINK \l "_Toc355351152" 4.0 Discussion / conclusion PAGEREF _Toc355351152 \h 21
HYPERLINK \l "_Toc355351153" BIBLIOGRAPHY PAGEREF _Toc355351153 \h 23
List of figures
TOC \h \z \c "Figure" HYPERLINK \l "_Toc355351154" Figure 1. Malaria Life Cycle PAGEREF _Toc355351154 \h 2
HYPERLINK \l "_Toc355351155" Figure 2. Global distribution of relative risk of an EID event (2) PAGEREF _Toc355351155 \h 8
HYPERLINK \l "_Toc355351156" Figure 3A. Temperature Change 1990-2012 (15) PAGEREF _Toc355351156 \h 10
Figure 3B. Temperature Change 1990-2012 (15)..........................................................................11
preface
This thesis essay would not be possible without the support of the following people:
Dr. Linda Frank: I would like to thank my primary advisor, Dr. Linda Frank for valuable guidance and support throughout this literature review. Without your invaluable assistance, motivation, and extensive knowledge, this review would not have been successful.
Dr. Lee Harrison: I would like to thank my committee member, Dr. Lee Harrison, for providing general advice, reviewing drafts, and providing helpful comments.
Dr. Nicholas Preston: I would like to thank my committee member, Dr. Nicholas Preston, for providing advice and extensive knowledge on the subject. I am highly indebted to Ecohealth Alliance and your wiliness to take me on as an intern; I would not have found the motivation behind this review.
Introduction
Global climate change has become a main protagonist in many aspects of environmental and ecology issues in the past 10 years. These issues have had effects on crops, local precipitation changes, changing weather patterns and loss of polar ice caps ADDIN EN.CITE Kasting200262(1)626217Kasting, J. F.Siefert, J. L.Department of Geosciences, 443 Deike, The Pennsylvania State University, University Park, PA 16802, USA. kasting@essc.psu.eduLife and the evolution of Earth's atmosphereScienceScienceScienceScienceScienceScience1066-82965570*AtmosphereBiological EvolutionCyanobacteria/*physiologyEarth (Planet)Eukaryota/*physiologyEuryarchaeota/*physiology*Evolution, PlanetaryMethane/metabolismNitrogen/metabolismNitrogen FixationOxygen/metabolismPhotosynthesisSymbiosisWater Microbiology2002May 101095-9203 (Electronic)
0036-8075 (Linking)12004117http://www.ncbi.nlm.nih.gov/pubmed/1200411710.1126/science.1071184( HYPERLINK \l "_ENREF_1" \o "Kasting, 2002 #62" 1). Its effects however may be on a myriad of prokaryotic and eukaryotic life forms, ranging from ocean bacteriophages to bacteria, algae, invertebrates and vertebrate life forms ADDIN EN.CITE Kasting200262(1)626217Kasting, J. F.Siefert, J. L.Department of Geosciences, 443 Deike, The Pennsylvania State University, University Park, PA 16802, USA. kasting@essc.psu.eduLife and the evolution of Earth's atmosphereScienceScienceScienceScienceScienceScience1066-82965570*AtmosphereBiological EvolutionCyanobacteria/*physiologyEarth (Planet)Eukaryota/*physiologyEuryarchaeota/*physiology*Evolution, PlanetaryMethane/metabolismNitrogen/metabolismNitrogen FixationOxygen/metabolismPhotosynthesisSymbiosisWater Microbiology2002May 101095-9203 (Electronic)
0036-8075 (Linking)12004117http://www.ncbi.nlm.nih.gov/pubmed/1200411710.1126/science.1071184( HYPERLINK \l "_ENREF_1" \o "Kasting, 2002 #62" 1). In terms of infectious diseases, these changes may also affect a wide range of vectors and hosts. An evolving area in which climate changes may be inter-related to infectious diseases and pubic health are starting to be investigated. Of the infectious diseases that could have serious public health implications, understanding malaria and quantifying its effects on transmission and disease burden, is significant for control and reduction.
Emerging infectious diseases (EIDs) are a significant burden on global economics and public health ADDIN EN.CITE Jones200810(2)101017Jones, K. E.Patel, N. G.Levy, M. A.Storeygard, A.Balk, D.Gittleman, J. L.Daszak, P.Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK.Global trends in emerging infectious diseasesNatureNatureNatureNatureNatureNature990-34517181AnimalsCommunicable Diseases, Emerging/*epidemiology/microbiology/transmission/virologyDatabases, FactualDrug Resistance, MicrobialEnvironmentGeographyHumansIncidenceRiskSocioeconomic FactorsZoonoses/epidemiology/microbiology/transmission/virology2008Feb 211476-4687 (Electronic)
0028-0836 (Linking)18288193http://www.ncbi.nlm.nih.gov/pubmed/1828819310.1038/nature06536( HYPERLINK \l "_ENREF_2" \o "Jones, 2008 #10" 2). This preventable disease costs an estimated $12 billion dollars per year by governmental agencies and infected individuals ADDIN EN.CITE Control201220(3)202046Centers for Disease ControlCDC's Malaria Program2012Atlanta, GeorgiaCeneter for Global Healthhttp://www.cdc.gov/malaria/resources/pdf/fsp/cdc_malaria_program.pdfCenters for Disease Control ( HYPERLINK \l "_ENREF_3" \o "Control, 2012 #20" 3). Malaria is an infectious disease in which a female Anopheles mosquito transmits a Plasmodium falciparum parasite into a human host. This particular parasite is responsible for the most human deaths from malaria ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_4" \o "Le Roch, 2003 #64" 4). Once the parasite enters the human host it replicates in the liver and is than transmitted into red blood cells ADDIN EN.CITE CDC201213(5)131312CDC20132012Centers for Disease Control and Preventionhttp://www.cdc.gov/malaria/about/biology/mosquitoes/( HYPERLINK \l "_ENREF_5" \o "CDC, 2012 #13" 5). Once in the red blood cells, symptoms of malaria occur, which may differ depending on the individual, but include a combination of fever, chill, sweats, headaches, body aches, vomiting, and general malaise ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_4" \o "Le Roch, 2003 #64" 4). The life cycle of malaria is continuous through the exchange of parasites through its mosquito vector from the human host. During the red blood cell stage of human malaria, the disease can be spread through a bite of a mosquito and injected into another human ADDIN EN.CITE CDC201213(5)131312CDC20132012Centers for Disease Control and Preventionhttp://www.cdc.gov/malaria/about/biology/mosquitoes/( HYPERLINK \l "_ENREF_5" \o "CDC, 2012 #13" 5).
Figure SEQ Figure \* ARABIC 1. Malaria Life Cycle
The World Health Organization (WHO) reported a total of 660,000 deaths globally in 2010 from malaria, with 90% of them derived from African regions, and over 40% from Niger, Congo, and the Democratic Republic of Congo ADDIN EN.CITE Organization201365(6)656546World Health OrganizationMalaria2013http://www.who.int/topics/malaria/en/( HYPERLINK \l "_ENREF_6" \o "Organization, 2013 #65" 6). Transmission of malaria can amplified through factors such as mosquito intensity, temperature changes, and environmental influences. In the rapidly urbanizing area of Sub-Saharan Africa, there are 10 Anopheles species responsible for transmission, compared to only three main species in eastern Africa and the African Islands ADDIN EN.CITE Robert200311(7)111117Robert, V.Macintyre, K.Keating, J.Trape, J. F.Duchemin, J. B.Warren, M.Beier, J. C.Institut de Recherche pour le Developpement, France. robert@pasteur.mgMalaria transmission in urban sub-Saharan AfricaAm J Trop Med HygThe American journal of tropical medicine and hygieneAm J Trop Med HygThe American journal of tropical medicine and hygieneAm J Trop Med HygThe American journal of tropical medicine and hygiene169-76682Africa South of the Sahara/epidemiologyAnimalsCulicidaeHumans*Insect VectorsMalaria/*epidemiology/*transmissionUrban Health2003Feb0002-9637 (Print)
0002-9637 (Linking)12641407http://www.ncbi.nlm.nih.gov/pubmed/12641407( HYPERLINK \l "_ENREF_7" \o "Robert, 2003 #11" 7). These additional species contribute to the public health epidemic in central and western Africa by providing faster transmission of disease. Future climate change has an enormous potential to evoke severe consequences with on human lives ADDIN EN.CITE Blanford201363(8)636317Blanford, J. I.Blanford, S.Crane, R. G.Mann, M. E.Paaijmans, K. P.Schreiber, K. V.Thomas, M. B.GeoVISTA Center, Department of Geography, The Pennsylvania State University, University Park, PA, USA. jib18@psu.eduImplications of temperature variation for malaria parasite development across AfricaSci RepScientific reportsSci RepScientific reportsSci RepScientific reports130032013Feb 182045-2322 (Electronic)
2045-2322 (Linking)23419595http://www.ncbi.nlm.nih.gov/pubmed/23419595357511710.1038/srep01300( HYPERLINK \l "_ENREF_8" \o "Blanford, 2013 #63" 8). Multiple studies have shown that temperature is an additional driver of mosquito traits such as, transmission intensity, mosquito development, incidence of biting and replication rate of parasites within the mosquito ADDIN EN.CITE Mordecai201366(9)666617Mordecai, E. A.Paaijmans, K. P.Johnson, L. R.Balzer, C.Ben-Horin, T.de Moor, E.McNally, A.Pawar, S.Ryan, S. J.Smith, T. C.Lafferty, K. D.Ecology, Evolution, and Marine Biology Department, University of California, Santa Barbara, CA 93106, USA. Mordecai@lifesci.ucsb.eduOptimal temperature for malaria transmission is dramatically lower than previously predictedEcol LettEcology lettersEcol LettEcology lettersEcol LettEcology letters22-301612013Jan1461-0248 (Electronic)
1461-023X (Linking)23050931http://www.ncbi.nlm.nih.gov/pubmed/2305093110.1111/ele.12015( HYPERLINK \l "_ENREF_9" \o "Mordecai, 2013 #66" 9). In lower latitudes areas where disease reporting is low, such as sub-Saharan Africa, climate change is hypothesized to drive emergence of infectious diseases ADDIN EN.CITE Jones200810(2)101017Jones, K. E.Patel, N. G.Levy, M. A.Storeygard, A.Balk, D.Gittleman, J. L.Daszak, P.Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK.Global trends in emerging infectious diseasesNatureNatureNatureNatureNatureNature990-34517181AnimalsCommunicable Diseases, Emerging/*epidemiology/microbiology/transmission/virologyDatabases, FactualDrug Resistance, MicrobialEnvironmentGeographyHumansIncidenceRiskSocioeconomic FactorsZoonoses/epidemiology/microbiology/transmission/virology2008Feb 211476-4687 (Electronic)
0028-0836 (Linking)18288193http://www.ncbi.nlm.nih.gov/pubmed/1828819310.1038/nature06536( HYPERLINK \l "_ENREF_2" \o "Jones, 2008 #10" 2). Additionally, a recent study on global trends in EIDs, presented additional that highlights the importance of environmental factors on pathogen transmission ADDIN EN.CITE Jones200810(2)101017Jones, K. E.Patel, N. G.Levy, M. A.Storeygard, A.Balk, D.Gittleman, J. L.Daszak, P.Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK.Global trends in emerging infectious diseasesNatureNatureNatureNatureNatureNature990-34517181AnimalsCommunicable Diseases, Emerging/*epidemiology/microbiology/transmission/virologyDatabases, FactualDrug Resistance, MicrobialEnvironmentGeographyHumansIncidenceRiskSocioeconomic FactorsZoonoses/epidemiology/microbiology/transmission/virology2008Feb 211476-4687 (Electronic)
0028-0836 (Linking)18288193http://www.ncbi.nlm.nih.gov/pubmed/1828819310.1038/nature06536( HYPERLINK \l "_ENREF_2" \o "Jones, 2008 #10" 2). This study looked at 335 EID events from 1990-2004 and found that 71.8% of these occurred from wildlife, with a majority of vector-borne pathogens occurring at lower latitudes. Over the specific time period, an increase in disease emergence was correlated with ecological and environmental factors. Some of the anthropogenic activity that has greatly influenced emergence is increased human population, deforestation, changes in agriculture and burning of fossil fuels ADDIN EN.CITE O'Meara201014(10)141417O'Meara, W. P.Mangeni, J. N.Steketee, R.Greenwood, B.George Washington University, USA.Changes in the burden of malaria in sub-Saharan AfricaLancet Infect DisThe Lancet infectious diseasesLancet Infect DisThe Lancet infectious diseasesLancet Infect DisThe Lancet infectious diseases545-55108Africa South of the Sahara/epidemiology*Cost of IllnessHumansMalaria/*economics/epidemiologyTime Factors2010Aug1474-4457 (Electronic)
1473-3099 (Linking)20637696http://www.ncbi.nlm.nih.gov/pubmed/2063769610.1016/S1473-3099(10)70096-7( HYPERLINK \l "_ENREF_10" \o "O'Meara, 2010 #14" 10). Research has shown that similar environmental factors have an influence of malaria transmission ADDIN EN.CITE Mordecai201366(9)666617Mordecai, E. A.Paaijmans, K. P.Johnson, L. R.Balzer, C.Ben-Horin, T.de Moor, E.McNally, A.Pawar, S.Ryan, S. J.Smith, T. C.Lafferty, K. D.Ecology, Evolution, and Marine Biology Department, University of California, Santa Barbara, CA 93106, USA. Mordecai@lifesci.ucsb.eduOptimal temperature for malaria transmission is dramatically lower than previously predictedEcol LettEcology lettersEcol LettEcology lettersEcol LettEcology letters22-301612013Jan1461-0248 (Electronic)
1461-023X (Linking)23050931http://www.ncbi.nlm.nih.gov/pubmed/2305093110.1111/ele.12015( HYPERLINK \l "_ENREF_9" \o "Mordecai, 2013 #66" 9).
The natural history of the epidemiology of malaria, in combination with several human and environmental impacts, has contributed to climate change, resulting in enormous impacts on the incidence and prevalence of malaria ADDIN EN.CITE Edlund20123(11)3317Edlund, S.Davis, M.Douglas, J. V.Kershenbaum, A.Waraporn, N.Lessler, J.Kaufman, J. H.IBM Almaden Research Center, San Jose, CA 95120, USA.A global model of malaria climate sensitivity: comparing malaria response to historic climate data based on simulation and officially reported malaria incidenceMalar JMalaria journalMalar JMalaria journalMalar JMalaria journal33111AnimalsAnopheles/*growth & development*Climate Change*Disease VectorsHumansIncidenceMalaria/*epidemiology/*transmissionModels, StatisticalWorld Health20121475-2875 (Electronic)
1475-2875 (Linking)22988975http://www.ncbi.nlm.nih.gov/pubmed/22988975350244110.1186/1475-2875-11-331( HYPERLINK \l "_ENREF_11" \o "Edlund, 2012 #3" 11). Studies have concluded that a portion of natural factors that significantly contribute to malaria transmission are temperature and precipitation ADDIN EN.CITE Gething20112(12)2217Gething, P. W.Van Boeckel, T. P.Smith, D. L.Guerra, C. A.Patil, A. P.Snow, R. W.Hay, S. I.Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, UK. peter.gething@zoo.ox.ac.ukModelling the global constraints of temperature on transmission of Plasmodium falciparum and P. vivaxParasit VectorsParasites & vectorsParasit VectorsParasites & vectorsParasit VectorsParasites & vectors924ClimateEnvironmentGeographyHumansMalaria, Falciparum/*transmissionMalaria, Vivax/*transmissionModels, StatisticalPlasmodium falciparum/*pathogenicity/radiation effectsPlasmodium vivax/*pathogenicity/radiation effectsSeasonsTemperature20111756-3305 (Electronic)
1756-3305 (Linking)21615906http://www.ncbi.nlm.nih.gov/pubmed/21615906311589710.1186/1756-3305-4-92( HYPERLINK \l "_ENREF_12" \o "Gething, 2011 #2" 12). On the opposite end of the spectrum anthropogenic factors that aid in climatic change include burning of fossil fuels, deforestation, and changes in agricultural practice ADDIN EN.CITE Rosenzweig20019(13)9917Rosenzweig, C.Climate Change and extreme weather events: Implications for food production, plant diseases, and pests. Global Change and Human Health
90-104222001( HYPERLINK \l "_ENREF_13" \o "Rosenzweig, 2001 #9" 13). These factors contribute to negative health impacts of malaria in Central and Western African areas.
The preventative measures for malaria must consider the future implications of this disease. Developing technology such as modeling and genomic sequencing, could greatly impact public health preventative measures. The use of modeling techniques provide the ability to provide predictive measures involving complex aspects of the life cycle of malaria and climate change. Additionally, through genetic sequencing, new drug targets and proteins involved in malaria can be identified for preventative interventions in pathogenicity ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_4" \o "Le Roch, 2003 #64" 4). Large scale genomic variation studies could assist in efforts to eliminate malaria in the future ADDIN EN.CITE Malaria Genomic Epidemiology200867(14)676717Malaria Genomic Epidemiology, NetworkThe University of Buea, PO Box 63, Buea, South West Province, Cameroon.A global network for investigating the genomic epidemiology of malariaNatureNatureNatureNatureNatureNature732-74567223AnimalsAnopheles/geneticsEpidemiologic Research DesignGenome, Human/*geneticsGenome-Wide Association StudyHumansImmunity, Innate/geneticsMalaria/*epidemiology/*geneticsPlasmodium/geneticsPolymorphism, Single NucleotideWorld Health2008Dec 111476-4687 (Electronic)
0028-0836 (Linking)19079050http://www.ncbi.nlm.nih.gov/pubmed/1907905010.1038/nature07632( HYPERLINK \l "_ENREF_14" \o "Malaria Genomic Epidemiology, 2008 #67" 14).
Technology coupled with additional emphasis on educational prevention on can help to diminish the effect of malaria and climate change. The public health importance of this review is critical not only to African Regions, but for global health as a whole. It is a valuable educational tool that highlights the need for additional research in the areas of climate change and vector response, environmental influences, prevention, policy, and contributes to the public health issue of malaria in the fight for Central and Western African health and potential global health in the future.
Methods
An initial online search was conducted to analyze the impacts of climate change globally through the National Aeronautics and Space Administrations global climate online resource. Data was collected on global temperature change and precipitation rates. Information was then gathered through online search databases on the locations where malaria incidence and prevalence rates were the highest. These databases included Google Scholar, PubMed, the University of Pittsburghs digital library (PittCat), and through Columbia Universitys digital library. References were also collected from an online library through an open source tool titled Zotero. This library was comprised during the summer of 2012 during a practicum experience at EcoHealth Alliance. Additional information was collected from the Government affiliated websites, The World Health Organization (WHO) and Centers for Disease Control (CDC) websites were used to gather credible information on malaria. Western and Central African were locations identified as regions where malaria is endemic, research was then focused on that location and climate change was then assessed in those areas.
A search strategy was then conducted through keywords and phrases. These included terms such as global climate change, epidemiology of malaria, sub-Saharan Africa and malaria, malaria transmission rates, public health policy and malaria, malaria prevention, predictive modeling and malaria, temperature change and malaria, implications of temperature change and health, prevention and malaria, surveillance response and malaria. After using those search terms and specified databases over 2000 references were identified and an inclusion and exclusion criteria was used. The years published must have been from 2000-present, (with the exception of Ronald Ross reference), must be full-text products, and peer reviewed journal articles. References were then evaluated based on importance and pertinence. Evaluation criteria were based on inclusion and exclusion criteria that would provide the most recent and credible sources. After all search criteria was assessed, 30 papers were reviewed specifically, which provided gaps in research and information for the literature review. The review of the literature collectively accumulated past and present research efforts to assess and answer research questions related to the public health burden of malaria in central and western Africa. Collected articles were stored in Zotero and Endnote was used for formatting the bibliography.
One of the limitations of this literature review was that minimal information was available for the surveillance and predicative tools regarding malaria prevention. Technology is currently developing in these areas, thus providing limited search results. Another limitation was a lack of literature on developing policy regarding interventions and preventative measures. New policies will be based on emerging epidemiological evidence from modeling, causing limited information to review. Previous implemented policy measures were therefore included.
The results of the literature search and search criteria created a quality problem statement of high public health significance and relevance.
Problem Statement
Malaria is a current public health burden for central and western Africa and has the potential to become an increased problem with future climate change. This infectious disease affects all individuals in these areas regardless of age, sex, or socio-economic status. Quantitative analysis of research is needed to have a better understanding of prevention methods, impacts of predictive modeling for climate on vector transmission, and how policy has contributed to the fight against malaria. These components have the potential to provide insight on new control and reduction methods with a strong emphasis on future climate changes. This literature review emphasizes the need for research in these areas and highlights the high public health significance of malaria and climate change in central and western Africa.
Research Questions
What geographical areas in the world are most affected by climate change and possible increases of malaria?
How do public health measures and related research contribute to the current and future prevention and control of malaria?
How do environmental factors contribute to climate change?
What gaps in research and policy are needed for the future?
findings/results
What areas in the world are most affected by climate change and increase incidence of malaria?
EIDs continuously affect individuals globally through different paths of transmission. In a global distribution of relative risk of EID events, African countries have shown the largest volume of vector-borne disease in a concentrated area ADDIN EN.CITE Jones200810(2)101017Jones, K. E.Patel, N. G.Levy, M. A.Storeygard, A.Balk, D.Gittleman, J. L.Daszak, P.Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK.Global trends in emerging infectious diseasesNatureNatureNatureNatureNatureNature990-34517181AnimalsCommunicable Diseases, Emerging/*epidemiology/microbiology/transmission/virologyDatabases, FactualDrug Resistance, MicrobialEnvironmentGeographyHumansIncidenceRiskSocioeconomic FactorsZoonoses/epidemiology/microbiology/transmission/virology2008Feb 211476-4687 (Electronic)
0028-0836 (Linking)18288193http://www.ncbi.nlm.nih.gov/pubmed/1828819310.1038/nature06536( HYPERLINK \l "_ENREF_2" \o "Jones, 2008 #10" 2).
Figure SEQ Figure \* ARABIC 2. Global distribution of relative risk of an EID event (2)
[Green (lower risk) to red (higher risk).]
Of these infectious diseases, malaria is a preventable and treatable one that continues to burden many parts of the world annually. The 2012 malaria report states that there are currently 104 endemic countries where malaria is a burden ADDIN EN.CITE Organization201365(6)656546World Health OrganizationMalaria2013http://www.who.int/topics/malaria/en/( HYPERLINK \l "_ENREF_6" \o "Organization, 2013 #65" 6). Of the 25 countries that make up Central and Western Africa, 23 of those are part of malaria endemic areas. The populations in these areas are continuing to grow at a rapid rate, which enables transmission to thrive in urban areas. Robert et al. reported that the populations in sub-Saharan Africa were estimated at 784 million individuals and by 2025 estimates are approximated to be more then 1.2 billion. This is equivalent to a 2% increase in urbanization in the last 30 years, doubling every 37 years. Population factors impact transmission in terms of increased pollution which has effects on larval habits, life cycles and vector capacity of Anopheles mosquitoes ADDIN EN.CITE Robert200311(7)111117Robert, V.Macintyre, K.Keating, J.Trape, J. F.Duchemin, J. B.Warren, M.Beier, J. C.Institut de Recherche pour le Developpement, France. robert@pasteur.mgMalaria transmission in urban sub-Saharan AfricaAm J Trop Med HygThe American journal of tropical medicine and hygieneAm J Trop Med HygThe American journal of tropical medicine and hygieneAm J Trop Med HygThe American journal of tropical medicine and hygiene169-76682Africa South of the Sahara/epidemiologyAnimalsCulicidaeHumans*Insect VectorsMalaria/*epidemiology/*transmissionUrban Health2003Feb0002-9637 (Print)
0002-9637 (Linking)12641407http://www.ncbi.nlm.nih.gov/pubmed/12641407( HYPERLINK \l "_ENREF_7" \o "Robert, 2003 #11" 7). The public health significance of this problem is apparent in the hospital admissions rates, in which more then 15% are due to malaria ADDIN EN.CITE Robert200311(7)111117Robert, V.Macintyre, K.Keating, J.Trape, J. F.Duchemin, J. B.Warren, M.Beier, J. C.Institut de Recherche pour le Developpement, France. robert@pasteur.mgMalaria transmission in urban sub-Saharan AfricaAm J Trop Med HygThe American journal of tropical medicine and hygieneAm J Trop Med HygThe American journal of tropical medicine and hygieneAm J Trop Med HygThe American journal of tropical medicine and hygiene169-76682Africa South of the Sahara/epidemiologyAnimalsCulicidaeHumans*Insect VectorsMalaria/*epidemiology/*transmissionUrban Health2003Feb0002-9637 (Print)
0002-9637 (Linking)12641407http://www.ncbi.nlm.nih.gov/pubmed/12641407( HYPERLINK \l "_ENREF_7" \o "Robert, 2003 #11" 7). These large populations are not exclusively the cause of the high malaria incidence in these areas, but coupled with changing climate, it makes for a lethal combination.
The global climate has been steadily changing over the past years in multiple aspects including temperature and precipitation. Over the years of 2009-2012 alone, there was a 13.6-degree increase in land and ocean temperatures ADDIN EN.CITE Administration201312(15)121212National Oceanic and Atmospheric AdministrationSignifigant Climate Annomolies1/17/20132013http://www.ncdc.noaa.govNOAA( HYPERLINK \l "_ENREF_15" \o "Administration, 2013 #12" 15). Western and Central Africa have felt the effects of these changes and experienced major natural disasters that have contributed to optimal malaria conditions. One of the most important factors in Anopheles breeding is temperature and humidity, where higher temperatures and stagnant water sources accelerate parasite growth in the mosquito ADDIN EN.CITE CDC201213(5)131312CDC20132012Centers for Disease Control and Preventionhttp://www.cdc.gov/malaria/about/biology/mosquitoes/( HYPERLINK \l "_ENREF_5" \o "CDC, 2012 #13" 5). In 2012, Western Africa experienced severe flooding during the months of July through September. According to the National Oceanic and Atmospheric Administration, 2012 was also reported as the 10th warmest year since 1880, marking the 36th consecutive year that global temperatures were above the average. Previously, the years 2010, and 2011 recorded the highest precipitation to date and 2010 manifested the warmest year to date. In 2010, there was the biggest shift in the El Nino-Southern Oscillation, which has a large influence on temperature precipitation globally ADDIN EN.CITE Administration201312(15)121212National Oceanic and Atmospheric AdministrationSignifigant Climate Annomolies1/17/20132013http://www.ncdc.noaa.govNOAA( HYPERLINK \l "_ENREF_15" \o "Administration, 2013 #12" 15). This shift has resulted in wetter-than-normal conditions in Western Africa, and drier than normal conditions over equatorial Central and East Africa ADDIN EN.CITE Collins201068(16)686817Collins, M.The impact of global warming on the tropical Pacific Ocean and El NioNature GeoscienceNature Geoscience391-39732010http://www.nature.com/ngeo/journal/v3/n6/abs/ngeo868.html10.1038/ngeo868( HYPERLINK \l "_ENREF_16" \o "Collins, 2010 #68" 16). These climate anomalies have and will continue to impact malaria transmission rates unless drastic prevention methods are incorporated across Western and Central Africa ADDIN EN.CITE Mordecai201366(9)666617Mordecai, E. A.Paaijmans, K. P.Johnson, L. R.Balzer, C.Ben-Horin, T.de Moor, E.McNally, A.Pawar, S.Ryan, S. J.Smith, T. C.Lafferty, K. D.Ecology, Evolution, and Marine Biology Department, University of California, Santa Barbara, CA 93106, USA. Mordecai@lifesci.ucsb.eduOptimal temperature for malaria transmission is dramatically lower than previously predictedEcol LettEcology lettersEcol LettEcology lettersEcol LettEcology letters22-301612013Jan1461-0248 (Electronic)
1461-023X (Linking)23050931http://www.ncbi.nlm.nih.gov/pubmed/2305093110.1111/ele.12015( HYPERLINK \l "_ENREF_9" \o "Mordecai, 2013 #66" 9).
Figure SEQ Figure \* ARABIC 3A. Temperature Change 1990-2012 (15)
Figure 3B. Temperature Change 1990-2012 (15)
Prevention methods have been put in place and positive results are being observed in certain areas. In the previous 5 years there has been a decline of an average of 50-70% in incidence in the areas of African Islands and Southern Africa. Although in terms of Central and Western Africa deteriorating conditions are occurring and there has not been significant decline in malaria incidence ADDIN EN.CITE O'Meara201014(10)141417O'Meara, W. P.Mangeni, J. N.Steketee, R.Greenwood, B.George Washington University, USA.Changes in the burden of malaria in sub-Saharan AfricaLancet Infect DisThe Lancet infectious diseasesLancet Infect DisThe Lancet infectious diseasesLancet Infect DisThe Lancet infectious diseases545-55108Africa South of the Sahara/epidemiology*Cost of IllnessHumansMalaria/*economics/epidemiologyTime Factors2010Aug1474-4457 (Electronic)
1473-3099 (Linking)20637696http://www.ncbi.nlm.nih.gov/pubmed/2063769610.1016/S1473-3099(10)70096-7( HYPERLINK \l "_ENREF_10" \o "O'Meara, 2010 #14" 10). With increasing climate conditions and decreasing effectiveness of prevention programs, malaria is a public health emergency in Western and Central African regions.
how do enviromental factors contribute to climate change?
Understanding the factors that assistant in climate change will help malaria prevention initiatives in the future. The human population is largely responsible for contributing to changes in anthropogenic land use and human ecology for emerging infectious diseases in terms of climate. One study found that a rise in emergence and re-emergence of infectious disease is related to climate anomalies beginning in the 1990s and found supporting evidence that climate change drives the emergence of diseases that have sensitive vectors to environmental conditions, such as temperature and rainfall ADDIN EN.CITE Jones200810(2)101017Jones, K. E.Patel, N. G.Levy, M. A.Storeygard, A.Balk, D.Gittleman, J. L.Daszak, P.Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK.Global trends in emerging infectious diseasesNatureNatureNatureNatureNatureNature990-34517181AnimalsCommunicable Diseases, Emerging/*epidemiology/microbiology/transmission/virologyDatabases, FactualDrug Resistance, MicrobialEnvironmentGeographyHumansIncidenceRiskSocioeconomic FactorsZoonoses/epidemiology/microbiology/transmission/virology2008Feb 211476-4687 (Electronic)
0028-0836 (Linking)18288193http://www.ncbi.nlm.nih.gov/pubmed/1828819310.1038/nature06536( HYPERLINK \l "_ENREF_2" \o "Jones, 2008 #10" 2). The Anopheles mosquito vector is particularly sensitive to fluctuations in temperature. One study found that in addition to average temperature, daily changes affect the rate of parasite growth and increase virulence ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_17" \o "Paaijmans, 2010 #15" 17). Adapting to these fluctuations make it possible for transmission to occur at lower mean temperature levels, therefore increasing transmission rates ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_17" \o "Paaijmans, 2010 #15" 17). Data from the project, mapping malaria risk in Africa (MARA) determined projections of potential transmission changes due to predicted changes in climate. By the 2080s scientist have predicted the number of people at risk for flooding to increase from 75 million to 200 million, with increased ambient temperatures to follow ADDIN EN.CITE Patz200516(18)161617Patz, J. A.Campbell-Lendrum, D.Holloway, T.Foley, J. A.Center for Sustainability and the Global Environment (SAGE), Nelson Institute for Environmental Studies, University of Wisconsin, 1710 University Avenue, Madison, Wisconsin 53726, USA. patz@wisc.eduImpact of regional climate change on human healthNatureNatureNatureNatureNatureNature310-74387066AnimalsDisease Vectors*Greenhouse EffectHeat Stroke/epidemiology/etiology/mortalityHumansInfection/epidemiology/etiology*Public Health/statistics & numerical data/trendsWorld Health2005Nov 171476-4687 (Electronic)
0028-0836 (Linking)16292302http://www.ncbi.nlm.nih.gov/pubmed/1629230210.1038/nature04188( HYPERLINK \l "_ENREF_18" \o "Patz, 2005 #16" 18). Researchers have predicted that without an increase in population, which is inevitable, there will be a 16-28% increase in people exposed each month to malaria ADDIN EN.CITE Patz200516(18)161617Patz, J. A.Campbell-Lendrum, D.Holloway, T.Foley, J. A.Center for Sustainability and the Global Environment (SAGE), Nelson Institute for Environmental Studies, University of Wisconsin, 1710 University Avenue, Madison, Wisconsin 53726, USA. patz@wisc.eduImpact of regional climate change on human healthNatureNatureNatureNatureNatureNature310-74387066AnimalsDisease Vectors*Greenhouse EffectHeat Stroke/epidemiology/etiology/mortalityHumansInfection/epidemiology/etiology*Public Health/statistics & numerical data/trendsWorld Health2005Nov 171476-4687 (Electronic)
0028-0836 (Linking)16292302http://www.ncbi.nlm.nih.gov/pubmed/1629230210.1038/nature04188( HYPERLINK \l "_ENREF_18" \o "Patz, 2005 #16" 18).
Changes in human activities such as; deforestation, burning of fossil fuels, human expansion, etc. are directly involved in the surge of infectious disease and climate change. The primary cause of anthropogenic change is due to the greenhouse effects caused by the burning of fossil fuels and clearing of forests. Humans have enhanced the natural green house effect by adding halo-carbons, particularly Chlorofluorocarbons (CFC), CFC11 and CFC12 to the atmosphere, which do not naturally occur in nature ADDIN EN.CITE Claussen200117(19)17176Claussen, E. Arroyo,V. DavisEileen ClaussenClimate Change: Science, Strategies, & Solutions.13452001Arlington, VirginiaPew Center on Global Climate Change9004120246( HYPERLINK \l "_ENREF_19" \o "Claussen, 2001 #17" 19). CFCs are nontoxic, nonflammable chemicals, used in the manufacturing of aerosol sprays, and packing materials ADDIN EN.CITE Elkins199969(20)696917ElkinsChlorofluorocarbons (CFCs)78-801999( HYPERLINK \l "_ENREF_20" \o "Elkins, 1999 #69" 20). They destroy the ozone layer in the stratosphere and enhance the natural greenhouse effect ADDIN EN.CITE 200970(21)707010Chlorofluorocarbons: An Overlooked Climate Threat2009210 Cannon House Office Building( HYPERLINK \l "_ENREF_21" \o ", 2009 #70" 21).
The normal green house effect is the warming of the earths surface to balance absorbed energy from the sun ADDIN EN.CITE Change200771(22)717146Intergovernmental Panel on Climate ChangeWorking Group ReportMitigation of Climate Change2007( HYPERLINK \l "_ENREF_22" \o "Change, 2007 #71" 22). Human involvement boosts this process and increases evaporation rates, in turn adding water vapors to the atmosphere ADDIN EN.CITE Claussen200117(19)17176Claussen, E. Arroyo,V. DavisEileen ClaussenClimate Change: Science, Strategies, & Solutions.13452001Arlington, VirginiaPew Center on Global Climate Change9004120246( HYPERLINK \l "_ENREF_19" \o "Claussen, 2001 #17" 19). With the increase of human activity there have been several studies focused on understanding the potential effects on the global climate.
Global climate models have predicted the effects of atmospheric concentrations and concluded an average global warming between 2.7-10.4 degrees Fahrenheit with an increase of precipitation from 5-15% by the end of the century ADDIN EN.CITE Rosenzweig20019(13)9917Rosenzweig, C.Climate Change and extreme weather events: Implications for food production, plant diseases, and pests. Global Change and Human Health
90-104222001( HYPERLINK \l "_ENREF_13" \o "Rosenzweig, 2001 #9" 13). These factors directly have and will continue to have an influence on malaria for years to come. These predicted global changes only increase the need to focus on prevention and policy for the public health fight against malaria.
how do public health measures and related research contribute to the current and future prevention and control of malaria?
Prevention efforts for malaria essentially began in 1910 when Sir Ronald Ross published The prevention of Malaria ADDIN EN.CITE Ross191018(23)18186Ross, RonaldThe Prevention of Malaria66919101910New YorkE. P Dutton & Companyhttp://books.google.com/books?id=PJQ-AAAAYAAJ&printsec=frontcover&dq=The+prevention+of+malaria&hl=en&sa=X&ei=lbpZUby9L7HI0gGv0IDIAQ&ved=0CDgQ6AEwAA#v=onepage&q=The%20prevention%20of%20malaria&f=false( HYPERLINK \l "_ENREF_23" \o "Ross, 1910 #18" 23). He deemed this disease a political disease that effects the welfare of entire countries and that prevention should be a significant part of public administration ADDIN EN.CITE Ross191018(23)18186Ross, RonaldThe Prevention of Malaria66919101910New YorkE. P Dutton & Companyhttp://books.google.com/books?id=PJQ-AAAAYAAJ&printsec=frontcover&dq=The+prevention+of+malaria&hl=en&sa=X&ei=lbpZUby9L7HI0gGv0IDIAQ&ved=0CDgQ6AEwAA#v=onepage&q=The%20prevention%20of%20malaria&f=false( HYPERLINK \l "_ENREF_23" \o "Ross, 1910 #18" 23). It was not until the 1940s that control efforts had shown an effect in which malaria was practically eliminated from North America, Europe and Asia. These prevention methods bypassed Central and Western Africa, where transmission intensity is much larger ADDIN EN.CITE Edlund20123(11)3317Edlund, S.Davis, M.Douglas, J. V.Kershenbaum, A.Waraporn, N.Lessler, J.Kaufman, J. H.IBM Almaden Research Center, San Jose, CA 95120, USA.A global model of malaria climate sensitivity: comparing malaria response to historic climate data based on simulation and officially reported malaria incidenceMalar JMalaria journalMalar JMalaria journalMalar JMalaria journal33111AnimalsAnopheles/*growth & development*Climate Change*Disease VectorsHumansIncidenceMalaria/*epidemiology/*transmissionModels, StatisticalWorld Health20121475-2875 (Electronic)
1475-2875 (Linking)22988975http://www.ncbi.nlm.nih.gov/pubmed/22988975350244110.1186/1475-2875-11-331( HYPERLINK \l "_ENREF_11" \o "Edlund, 2012 #3" 11). The use of dichlorodiphenyltrichloroethane (DDT), has been used since 1940 which kills the mosquito vector, interfering with the host environment relationship. Since this prevention method has been in place Anopheles mosquitos have developed a physiological resistance, making DDT an inferior prevention method in African regions with this primary vector ADDIN EN.CITE International1999-200319(24)191912Malaria Foundation InternationalMalaria Foundation InternationalIs DDT still effectiveand needed in malaria control?1999-2003http://www.malaria.org/DDTcosts.html 2013( HYPERLINK \l "_ENREF_24" \o "International, 1999-2003 #19" 24). Since the discovery of this resistance the CDC and WHO have implemented the following prevention methods: insecticide- treated bed nets, Artemisinin containing combination therapies, and indoor spraying of homes ADDIN EN.CITE Control201220(3)202046Centers for Disease ControlCDC's Malaria Program2012Atlanta, GeorgiaCeneter for Global Healthhttp://www.cdc.gov/malaria/resources/pdf/fsp/cdc_malaria_program.pdfCenters for Disease Control ( HYPERLINK \l "_ENREF_3" \o "Control, 2012 #20" 3). These prevention methods are currently apart of the Scale up for Impact, the national malaria control standard in Africa. This initiative is supported through the roll back malaria (RBM) initiative developed by the World Health Organization. The RBM program includes funding from over 500 partners from private sectors, nongovernmental and community based organizations, foundations, and research and academic foundations ADDIN EN.CITE 201322(25)222212Roll Back Malaria03/20/20132013http://rollbackmalaria.org/index.html( HYPERLINK \l "_ENREF_25" \o ", 2013 #22" 25).
The current and future impacts of climate continue to make malaria prevention of primary concern. One study concluded that there is evidence that suggest that malaria eradication in Africa is a feasible goal with the combined use of current interventions and future vaccines ADDIN EN.CITE Campell201123(26)232317Campell, D., SteketeeMalaria in Africa Can Be Eliminated.The American Journal of Tropical Medicine and HygieneAm J Trop Med HygThe American journal of tropical medicine and hygiene584-585854201110.4269/ajtmh.2011.11-0529( HYPERLINK \l "_ENREF_26" \o "Campell, 2011 #23" 26). A current vaccine, RTS,S/AS01, is undergoing the third phase of implementation that targets the pre-erythrocytic stage of the Plasmodium falciparum parasite in African infants ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_27" \o "Rts, 2012 #21" 27). The first endpoint during the trial resulted in efficacy for clinical and severe malaria in 55.8% of the treated group. This study has the potential to greatly influence the understanding of the relationship between exposure and immune response for malaria.
Research for understanding the complex interplay between climate and malaria transmission is greatly dependent on predictive models. Modeling studies focus on malaria estimates and transmission rates in regards to climate. One study created a model using the Anopheles mosquito and the effect climate has on the vector capacity ADDIN EN.CITE Edlund20123(11)3317Edlund, S.Davis, M.Douglas, J. V.Kershenbaum, A.Waraporn, N.Lessler, J.Kaufman, J. H.IBM Almaden Research Center, San Jose, CA 95120, USA.A global model of malaria climate sensitivity: comparing malaria response to historic climate data based on simulation and officially reported malaria incidenceMalar JMalaria journalMalar JMalaria journalMalar JMalaria journal33111AnimalsAnopheles/*growth & development*Climate Change*Disease VectorsHumansIncidenceMalaria/*epidemiology/*transmissionModels, StatisticalWorld Health20121475-2875 (Electronic)
1475-2875 (Linking)22988975http://www.ncbi.nlm.nih.gov/pubmed/22988975350244110.1186/1475-2875-11-331( HYPERLINK \l "_ENREF_11" \o "Edlund, 2012 #3" 11). They used historic climate variation data from 2000-2010 and researched how malaria increased or decreased due to fluctuations in climate. They used several mathematical equations looking at time, location, rainfall, temperature, rate of larval development, and total degree-days of development through a open source tool, the Spatiotemporal Epidemiological Modeller. When predictive results were compared to reported malaria cases there was a positive correlation. By looking at specific fluctuations, it gives scientist a tool to observe what locations displayed the most sensitivity to climate variability.
An additional study using predictive modeling observed the malaria transmission cycle and its dependence on temperature ADDIN EN.CITE Gething20112(12)2217Gething, P. W.Van Boeckel, T. P.Smith, D. L.Guerra, C. A.Patil, A. P.Snow, R. W.Hay, S. I.Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, UK. peter.gething@zoo.ox.ac.ukModelling the global constraints of temperature on transmission of Plasmodium falciparum and P. vivaxParasit VectorsParasites & vectorsParasit VectorsParasites & vectorsParasit VectorsParasites & vectors924ClimateEnvironmentGeographyHumansMalaria, Falciparum/*transmissionMalaria, Vivax/*transmissionModels, StatisticalPlasmodium falciparum/*pathogenicity/radiation effectsPlasmodium vivax/*pathogenicity/radiation effectsSeasonsTemperature20111756-3305 (Electronic)
1756-3305 (Linking)21615906http://www.ncbi.nlm.nih.gov/pubmed/21615906311589710.1186/1756-3305-4-92( HYPERLINK \l "_ENREF_12" \o "Gething, 2011 #2" 12). Using mathematical equations they created a biological model that used temperature dependence on the transmission cycle, with temperature data to evaluate a time-series of ideal susceptibility for transmission ADDIN EN.CITE Gething20112(12)2217Gething, P. W.Van Boeckel, T. P.Smith, D. L.Guerra, C. A.Patil, A. P.Snow, R. W.Hay, S. I.Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, UK. peter.gething@zoo.ox.ac.ukModelling the global constraints of temperature on transmission of Plasmodium falciparum and P. vivaxParasit VectorsParasites & vectorsParasit VectorsParasites & vectorsParasit VectorsParasites & vectors924ClimateEnvironmentGeographyHumansMalaria, Falciparum/*transmissionMalaria, Vivax/*transmissionModels, StatisticalPlasmodium falciparum/*pathogenicity/radiation effectsPlasmodium vivax/*pathogenicity/radiation effectsSeasonsTemperature20111756-3305 (Electronic)
1756-3305 (Linking)21615906http://www.ncbi.nlm.nih.gov/pubmed/21615906311589710.1186/1756-3305-4-92( HYPERLINK \l "_ENREF_12" \o "Gething, 2011 #2" 12). Three publically available models were created that can help to identify populations at risk and enhance mapping of areas that display increased Anopheles breeding. Combining these new technologies has the ability to inform public health professionals of regions who will most likely need an intervention if and when climate fluctuations occur ADDIN EN.CITE Edlund20123(11)3317Edlund, S.Davis, M.Douglas, J. V.Kershenbaum, A.Waraporn, N.Lessler, J.Kaufman, J. H.IBM Almaden Research Center, San Jose, CA 95120, USA.A global model of malaria climate sensitivity: comparing malaria response to historic climate data based on simulation and officially reported malaria incidenceMalar JMalaria journalMalar JMalaria journalMalar JMalaria journal33111AnimalsAnopheles/*growth & development*Climate Change*Disease VectorsHumansIncidenceMalaria/*epidemiology/*transmissionModels, StatisticalWorld Health20121475-2875 (Electronic)
1475-2875 (Linking)22988975http://www.ncbi.nlm.nih.gov/pubmed/22988975350244110.1186/1475-2875-11-331( HYPERLINK \l "_ENREF_11" \o "Edlund, 2012 #3" 11). These analyses were done with limited surveillance data in certain locations. With availability of monthly time sampling, there is the potential for 20 times the improvement in accuracy ADDIN EN.CITE Edlund20123(11)3317Edlund, S.Davis, M.Douglas, J. V.Kershenbaum, A.Waraporn, N.Lessler, J.Kaufman, J. H.IBM Almaden Research Center, San Jose, CA 95120, USA.A global model of malaria climate sensitivity: comparing malaria response to historic climate data based on simulation and officially reported malaria incidenceMalar JMalaria journalMalar JMalaria journalMalar JMalaria journal33111AnimalsAnopheles/*growth & development*Climate Change*Disease VectorsHumansIncidenceMalaria/*epidemiology/*transmissionModels, StatisticalWorld Health20121475-2875 (Electronic)
1475-2875 (Linking)22988975http://www.ncbi.nlm.nih.gov/pubmed/22988975350244110.1186/1475-2875-11-331( HYPERLINK \l "_ENREF_11" \o "Edlund, 2012 #3" 11). With increased surveillance and modeling techniques, plausible prevention and predicative methods can be put into place during an ever-changing global environment. Predictive models will impact public health decision-making in the future, and is the key component in understanding the potential effects of climate variation and transmission.
An additional research tool that will contribute to future prevention is through the use of genetic sequencing. One study recently sequenced the entire Plasmodium falciparum genome using an oligonucleotide array to express human profiles and stages of the malaria parasites life cycle ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_4" \o "Le Roch, 2003 #64" 4). An additional study found this parasite has a 23-megabase nuclear genome consists of 14 chromosomes, and encodes about 5,300 genes ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_28" \o "Gardner, 2002 #72" 28). Understanding the epidemiology of Plasmodium falciparum is extremely useful for comparative purposes. This technology will enable sampling of parasite, vector and host genomes in the field, providing information to support the development and monitoring of malaria control methods ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_28" \o "Gardner, 2002 #72" 28). This technology coupled with future sequencing data should be considered a starting point for identifying proteins for new vaccine targets ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_4" \o "Le Roch, 2003 #64" 4).
The combination of current prevention, potential vaccination, and predictive modeling are the public health measures that contribute to the current and future prevention and control of malaria not only Central and Western Africa, but globally as a whole.
what gaps in research and policy are needed for the future?
As malaria continues to impact central and western Africa, policies for prevention methods need to be established and improved to help fill the gaps in research services. There is not currently a licensed vaccine against malaria, which emphasizes how important research is in finding an effective eradication strategy in endemic areas. A recent study used research to effectively implement policy in moderate to high transmissibility endemic areas ADDIN EN.CITE Dicko201224(29)242417Dicko, A., Konare, M., Traore, D., Testa, J., Salamon, R. Doumbo, O. The implementation of malaria intermittent preventive trialtreatment with sulphadoxinepyrimethamine in infants reduced all-cause mortality in the district of Kolokani, Mali: results from a cluster randomized control.Malaria JournalMalar JMalaria journal1-61173201210.1186/1475-2875-11-73( HYPERLINK \l "_ENREF_29" \o "Dicko, 2012 #24" 29). A preventative study was aimed at infants through administering a curative dose of sulphadoxine-pyrimethamine (SP) during the time of DTP2, DTP3 and mumps vaccinations ADDIN EN.CITE Dicko201224(29)242417Dicko, A., Konare, M., Traore, D., Testa, J., Salamon, R. Doumbo, O. The implementation of malaria intermittent preventive trialtreatment with sulphadoxinepyrimethamine in infants reduced all-cause mortality in the district of Kolokani, Mali: results from a cluster randomized control.Malaria JournalMalar JMalaria journal1-61173201210.1186/1475-2875-11-73( HYPERLINK \l "_ENREF_29" \o "Dicko, 2012 #24" 29). The results from the trial reduced the incidence of malaria by 30% and it is now mandatory for infants regardless of symptoms or infection. In order for vaccine development to occur, understanding genetic epidemiology of malaria at the molecular level is needed. Genome sequences alone provide minimal relief to those suffering from malaria. There is currently only 35% of genes that code for Plasmodium falciparum proteins with an identifiable function for malaria ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_4" \o "Le Roch, 2003 #64" 4). The absence of routine genetic tools suggests that this percentage is unlikely to change if conventional serial methods are continued to be used to characterize encoded proteins ADDIN EN.CITE ADDIN EN.CITE.DATA ( HYPERLINK \l "_ENREF_4" \o "Le Roch, 2003 #64" 4). Molecular research needs to be accompanied by additional efforts to develop new methods for control, including new drugs and vaccines, through improved diagnostics and effective vector control techniques. The gap between research and policy needs to be considered and become a driving force for policy decision makers in the future.
A recent document was published on the importance of modeling research on shaping the financial situation in endemic countries ADDIN EN.CITE Omumbo201325(30)252517Omumbo, J. A.Noor, A. M.Fall, I. S.Snow, R. W.Malaria Public Health Department, Kenya Medical Research Institute/Oxford University/Wellcome Trust Research Programme, Nairobi, Kenya. judyomumbo@gmail.comHow well are malaria maps used to design and finance malaria control in Africa?PLoS OnePloS onePLoS OnePloS onePLoS OnePloS onee531988120131932-6203 (Electronic)
1932-6203 (Linking)23326398http://www.ncbi.nlm.nih.gov/pubmed/23326398354345010.1371/journal.pone.0053198( HYPERLINK \l "_ENREF_30" \o "Omumbo, 2013 #25" 30). In January 2002, the Global Funds application was implemented as a protocol to follow to apply for funding. Since then there has been an increased demand of epidemiological risk information in endemic areas before allocating funds. Through the use of modeling, epidemiological risks can be assessed and ranked in endemic areas, thus helping policy makers make evidence based decisions. Without research being the driving force, the successes of recent investment in malaria control will be lost unless until a more rational basis for financing is established ADDIN EN.CITE Omumbo201325(30)252517Omumbo, J. A.Noor, A. M.Fall, I. S.Snow, R. W.Malaria Public Health Department, Kenya Medical Research Institute/Oxford University/Wellcome Trust Research Programme, Nairobi, Kenya. judyomumbo@gmail.comHow well are malaria maps used to design and finance malaria control in Africa?PLoS OnePloS onePLoS OnePloS onePLoS OnePloS onee531988120131932-6203 (Electronic)
1932-6203 (Linking)23326398http://www.ncbi.nlm.nih.gov/pubmed/23326398354345010.1371/journal.pone.0053198( HYPERLINK \l "_ENREF_30" \o "Omumbo, 2013 #25" 30). Advanced research is the next step for future prevention for malaria and policy in central and western Africa and globally. With the predicted climate change and increased vector transmissibility, malaria needs to take a front seat for prevention policy.
There are challenges with malaria policy when dealing with upstream and downstream factors. An upstream factor is the policy and regulatory challenges that affect the development of interventions based on international regulations and international policy ADDIN EN.CITE Organization73(31)737346World Health OrganizationGlobal Malaria Action plan http://www.rbm.who.int/gmap/4-4.html( HYPERLINK \l "_ENREF_31" \o "Organization, #73" 31). International regulations are an issue because not all prevention products undergo a full review by authorities. This procedure has been criticized for long delays in implementation when malaria prevention is a high priority ADDIN EN.CITE Organization73(31)737346World Health OrganizationGlobal Malaria Action plan http://www.rbm.who.int/gmap/4-4.html( HYPERLINK \l "_ENREF_31" \o "Organization, #73" 31). Additionally, the international policy processes are important in prevention, but have also been accused of using time-consuming procedures. The downstream factors include quality control, and the adoption and enforcement of policies ADDIN EN.CITE Organization73(31)737346World Health OrganizationGlobal Malaria Action plan http://www.rbm.who.int/gmap/4-4.html( HYPERLINK \l "_ENREF_31" \o "Organization, #73" 31). There are challenges after upstream factors have created recommendations and policies. The lack of resources and capacity in malaria endemic countries cause problems in adoption of these policies due to funding problems. There is an issue with resources, needs, and implemented policy for malaria prevention due to gaps in upstream and downstream factors.
Implications for public health
Research
Future research has positive public health implications regarding malaria endemic countries. As technology advances at the molecular and computational levels, the host, environment, and agent triad has the potential to be disrupted. Future climate anomalies have the ability to severely increase the incidence and prevalence of malaria. Through understanding the life cycles of the Plasmodium falciparum parasite, prevention methods can begin to lessen these effects and eventually eradicate malaria. This review will help researchers to consider the gaps of knowledge between necessary molecular components as well as climate change and its impact on malaria.
Policy
Policy could have positive or negative implications on public health regarding malaria preventative strategies. With more of an emphasis of using epidemiological research for allocating funds prevention polices could be improved. Additional funding will help countries to implement policy and target need based areas. This review will help policy makers understand the importance of the timing of policy and recommendation on countries. The future climate impacts on malaria have serious public health implications on malaria endmic countries and additional policy procedures need to be put in place.
Public Education
The public health implication of public education is critical for public health prevention for malaria on a global scale. Understanding the impact of malaria on an individuals health, finances, and the environment is an essential tool for prevention. This review will educate the public on current and future implications of malaria and climate change. By understanding how human anthropogenic activity impacts climate, the public can begin to slowly work towards improving malaria prevention strategies.
Health professional education
The implications of health professional education on the issue of malaria and climate change are of high importance. With motivated, educated individuals, malaria prevention can be attacked from all aspects of research, funding, and policy. Understanding the public health significance of this review is valuable in understanding what questions still need answered and what aspects need to be improved.
4.0 Discussion / conclusion
Malaria is a current public health burden for central and western Africa and has the potential to become an increased problem with future climate change. This infectious disease affects all individuals in these areas regardless of age, sex, or socio-economic status. Quantitative analysis of research is needed to have a better understanding of prevention methods, impacts of predictive modeling and genetic sequencing for climate on vector transmission, and how policy has contributed to the fight against malaria. These components have the potential to provide insight on new control and reduction methods with a strong emphasis on future climate changes. The public health importance of this review is to help professionals from all fields to avoid becoming complacent regarding malaria prevention. It is a valuable educational tool that highlights the need for additional research in the areas of climate change and vector response, environmental influences, prevention, policy, and contributes to the public health issue of malaria in the fight for Central and Western African health and potential global health in the future.
In addition to specific research in central and western Africa, global education methods need to become a priority to decrease the impact of climate on disease. Humans need to have a better understanding of how their actions impact the earths climate and individual health. With increased awareness, the goal of global of malaria eradication can be achieved. Policy makers and researchers need to work together to better understand the future of this disease. Climate change should not be taken lightly and has the potential to have a huge impact on the health of the public. Malaria is one infectious disease that will be affected by increased temperature and precipitation. There will be additional public health problems that re-emerge in the future that have currently been contained. Public health prevention is essentially in lessening the severity of the impact of climate on disease. With increased collaboration and understanding of gaps in research, policy and educational methods, malaria eradication can be possible.
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31. Organization WH. Global Malaria Action plan
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PAGE 13
CURRENT AND FUTURE IMPACTS OF CLIMATE CHANGE ON MALARIA IN CENTRAL AND WESTERN AFRICA
by
Stephanie Lee Nara
BS, Utica College, 2011
Submitted to the Graduate Faculty of
Infectious Diseases and Microbiology
Graduate School of Public Health in partial fulfillment
of the requirements for the degree of
Master of Public Health
University of Pittsburgh
2013
UNIVERSITY OF PITTSBURGH
GRADUATE SCHOOL OF PUBLIC HEALTH
This essay is submitted
by
Stephanie Nara
on
May 3, 2013
and approved by
Essay Advisor:
Linda Frank, PhD, MSN, RN, ________________________________
ACRN, CS, FAAN
Associate Professor
Infectious Diseases and Microbiology
Graduate School of Public Health
University of Pittsburgh
Essay Reader:
Lee Harrison, MD, BS _________________________________
Professor, Epidemiology and Medicine
Graduate School of Public Health and School of Medicine
University of Pittsburgh
Essay Reader:
Nicholas Preston, PhD ________________________________
Senior Research Scientist
EcoHealth Alliance
New York, New York
Copyright by Stephanie Nara
2013
Linda Frank, PhD, MSN, RN, ACRN, CS, FAAN
CURRENT AND FUTURE IMPACTS OF CLIMATE CHANGE ON MALARIA IN CENTRAL AND WESTERN AFRICA
Stephanie Nara, MPH
University of Pittsburgh, 2013
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