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Marini G, Calzolari M, Angelini P, Bellini R, Bellini S, Bolzoni L, Torri D, Defilippo F, Dorigatti I, Nikolay B, Pugliese A, Rosà R, Tamba M. A quantitative comparison of West Nile virus incidence from 2013 to 2018 in Emilia-Romagna, Italy. PLoS Negl Trop Dis 2020; 14:e0007953. [PMID: 31895933 PMCID: PMC6939904 DOI: 10.1371/journal.pntd.0007953] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/20/2019] [Indexed: 12/01/2022] Open
Abstract
Background West Nile virus (WNV) transmission was much greater in 2018 than in previous seasons in Europe. Focusing on Emilia-Romagna region (northern Italy), we analyzed detailed entomological and epidemiological data collected in 2013–2018 to quantitatively assess environmental drivers of transmission and explore hypotheses to better understand why the 2018 epidemiological season was substantially different than the previous seasons. In particular, in 2018 WNV was detected at least two weeks before the observed circulation in 2013–2017 and in a larger number of mosquito pools. Transmission resulted in 100 neuroinvasive human cases in the region, more than the total number of cases recorded between 2013 and 2017. Methodology We used temperature-driven mathematical models calibrated through a Bayesian approach to simulate mosquito population dynamics and WNV infection rates in the avian population. We then estimated the human transmission risk as the probability, for a person living in the study area, of being bitten by an infectious mosquito in a given week. Finally, we translated such risk into reported WNV human infections. Principal findings The estimated prevalence of WNV in the mosquito and avian populations were significantly higher in 2018 with respect to 2013–2017 seasons, especially in the eastern part of the region. Furthermore, peak avian prevalence was estimated to have occurred earlier, corresponding to a steeper decline towards the end of summer. The high mosquito prevalence resulted in a much greater predicted risk for human transmission in 2018, which was estimated to be up to eight times higher than previous seasons. We hypothesized, on the basis of our modelling results, that such greater WNV circulation might be partially explained by exceptionally high spring temperatures, which have likely helped to amplify WNV transmission at the beginning of the 2018 season. West Nile virus (WNV) is one of the most recent emerging mosquito-borne diseases in Europe and North America. While most human infections are asymptomatic, about 1% of them can result in severe neurological diseases which might be fatal. WNV transmission was unusually greater in 2018 than in previous years in many European countries, resulting in a large number of human infections. Focusing on Emilia-Romagna region (Italy), we developed an epidemiological model informed by entomological data; through that we found that exceptionally high spring temperatures might have contributed at amplifying WNV transmission at the beginning of the season, causing greater WNV prevalence in mosquito and avian populations during the summer, which resulted in a higher estimated risk for human transmission. Thus, weather anomalies at the beginning of the mosquito breeding season, which are likely to become more common under the projected scenarios of climate change, might act as an early warning signal for public health authorities, enabling them to design efficient surveillance and prevention strategies.
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Affiliation(s)
- Giovanni Marini
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige (TN), Italy
- Epilab-JRU, FEM-FBK Joint Research Unit, Province of Trento, Italy
- * E-mail:
| | - Mattia Calzolari
- Laboratory of Entomology, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna “B. Ubertini”, Reggio Emilia, Italy
| | - Paola Angelini
- Public Health Service, Emilia-Romagna Region, Bologna, Italy
| | - Romeo Bellini
- Dept. Medical & Veterinary Entomology, Centro Agricoltura Ambiente “G. Nicoli”, Crevalcore, Italy
| | - Silvia Bellini
- Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna “B. Ubertini”, Bologna, Italy
| | - Luca Bolzoni
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna “B. Ubertini”, Parma, Italy
| | - Deborah Torri
- Laboratory of Entomology, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna “B. Ubertini”, Reggio Emilia, Italy
| | - Francesco Defilippo
- Laboratory of Entomology, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna “B. Ubertini”, Reggio Emilia, Italy
| | - Ilaria Dorigatti
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Birgit Nikolay
- Mathematical Modelling of Infectious Diseases Unit, Institut Pasteur, Paris, France
- CNRS UMR2000: Génomique évolutive, modélisation et santé, Institut Pasteur, Paris, France
- Center of Bioinformatics, Biostatistics and Integrative Biology, Institut Pasteur, Paris, France
| | - Andrea Pugliese
- Department of Mathematics, University of Trento, Trento, Italy
| | - Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige (TN), Italy
- Epilab-JRU, FEM-FBK Joint Research Unit, Province of Trento, Italy
- Center Agriculture Food Environment, University of Trento, San Michele all’Adige (TN), Italy
| | - Marco Tamba
- Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna “B. Ubertini”, Bologna, Italy
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Koolhof IS, Gibney KB, Bettiol S, Charleston M, Wiethoelter A, Arnold AL, Campbell PT, Neville PJ, Aung P, Shiga T, Carver S, Firestone SM. The forecasting of dynamical Ross River virus outbreaks: Victoria, Australia. Epidemics 2019; 30:100377. [PMID: 31735585 DOI: 10.1016/j.epidem.2019.100377] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 11/04/2019] [Accepted: 11/04/2019] [Indexed: 10/25/2022] Open
Abstract
Ross River virus (RRV) is Australia's most epidemiologically important mosquito-borne disease. During RRV epidemics in the State of Victoria (such as 2010/11 and 2016/17) notifications can account for up to 30% of national RRV notifications. However, little is known about factors which can forecast RRV transmission in Victoria. We aimed to understand factors associated with RRV transmission in epidemiologically important regions of Victoria and establish an early warning forecast system. We developed negative binomial regression models to forecast human RRV notifications across 11 Local Government Areas (LGAs) using climatic, environmental, and oceanographic variables. Data were collected from July 2008 to June 2018. Data from July 2008 to June 2012 were used as a training data set, while July 2012 to June 2018 were used as a testing data set. Evapotranspiration and precipitation were found to be common factors for forecasting RRV notifications across sites. Several site-specific factors were also important in forecasting RRV notifications which varied between LGA. From the 11 LGAs examined, nine experienced an outbreak in 2011/12 of which the models for these sites were a good fit. All 11 LGAs experienced an outbreak in 2016/17, however only six LGAs could predict the outbreak using the same model. We document similarities and differences in factors useful for forecasting RRV notifications across Victoria and demonstrate that readily available and inexpensive climate and environmental data can be used to predict epidemic periods in some areas. Furthermore, we highlight in certain regions the complexity of RRV transmission where additional epidemiological information is needed to accurately predict RRV activity. Our findings have been applied to produce a Ross River virus Outbreak Surveillance System (ROSS) to aid in public health decision making in Victoria.
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Affiliation(s)
- Iain S Koolhof
- College of Health and Medicine, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia; College of Sciences and Engineering, School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia.
| | - Katherine B Gibney
- Victorian Department of Health and Human Services, Communicable Disease Epidemiology and Surveillance, Health Protection Branch, Melbourne, Victoria, Australia; The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia; Department of Infectious Diseases, Austin Hospital, Melbourne, Victoria, Australia
| | - Silvana Bettiol
- College of Health and Medicine, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Michael Charleston
- College of Sciences and Engineering, School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Anke Wiethoelter
- Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Anna-Lena Arnold
- Victorian Department of Health and Human Services, Communicable Disease Epidemiology and Surveillance, Health Protection Branch, Melbourne, Victoria, Australia
| | - Patricia T Campbell
- The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia; Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Peter J Neville
- Victorian Department of Health and Human Services, Communicable Disease Epidemiology and Surveillance, Health Protection Branch, Melbourne, Victoria, Australia; Department of Health, Western Australia, Public and Aboriginal Health, Environmental Health Directorate, Perth, Western Australia, Australia
| | - Phyo Aung
- The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Tsubasa Shiga
- The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Scott Carver
- College of Sciences and Engineering, School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Simon M Firestone
- Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Melbourne, Victoria, Australia
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53
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Holmes CJ, Benoit JB. Biological Adaptations Associated with Dehydration in Mosquitoes. INSECTS 2019; 10:insects10110375. [PMID: 31661928 PMCID: PMC6920799 DOI: 10.3390/insects10110375] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 10/22/2019] [Accepted: 10/23/2019] [Indexed: 12/05/2022]
Abstract
Diseases that are transmitted by mosquitoes are a tremendous health and socioeconomic burden with hundreds of millions of people being impacted by mosquito-borne illnesses annually. Many factors have been implicated and extensively studied in disease transmission dynamics, but knowledge regarding how dehydration impacts mosquito physiology, behavior, and resulting mosquito-borne disease transmission remain underdeveloped. The lapse in understanding on how mosquitoes respond to dehydration stress likely obscures our ability to effectively study mosquito physiology, behavior, and vectorial capabilities. The goal of this review is to develop a profile of factors underlying mosquito biology that are altered by dehydration and the implications that are related to disease transmission.
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Affiliation(s)
- Christopher J Holmes
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH 45221, USA.
| | - Joshua B Benoit
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH 45221, USA.
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Sequeira J, Louçã J, Mendes AM, Lind PG. Transition from endemic behavior to eradication of malaria due to combined drug therapies: An agent-model approach. J Theor Biol 2019; 484:110030. [PMID: 31568789 DOI: 10.1016/j.jtbi.2019.110030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 09/14/2019] [Accepted: 09/26/2019] [Indexed: 01/05/2023]
Abstract
We introduce an agent-based model describing a susceptible-infectious-susceptible (SIS) system of humans and mosquitoes to predict malaria epidemiological scenarios in realistic biological conditions. Emphasis is given to the transition from endemic behavior to eradication of malaria transmission induced by combined drug therapies acting on both the gametocytemia reduction and on the selective mosquito mortality during parasite development in the mosquito. Our mathematical framework enables to uncover the critical values of the parameters characterizing the effect of each drug therapy. Moreover, our results provide quantitative evidence of what was up to now only partially assumed with empirical support: interventions combining gametocytemia reduction through the use of gametocidal drugs, with the selective action of ivermectin during parasite development in the mosquito, may actively promote disease eradication in the long run. In the agent model, the main properties of human-mosquito interactions are implemented as parameters and the model is validated by comparing simulations with real data of malaria incidence collected in the endemic malaria region of Chimoio in Mozambique. Finally, we discuss our findings in light of current drug administration strategies for malaria prevention, which may interfere with human-to-mosquito transmission process.
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Affiliation(s)
- João Sequeira
- Instituto Universitário de Lisboa (ISCTE-IUL), ISTAR-IUL, Av. das Forças Armadas, Lisboa 1649-026, Portugal; Hospital Santa Cruz, Av. Prof. Dr. Reinaldo dos Santos, Carnaxide 2790-134, Portugal
| | - Jorge Louçã
- Instituto Universitário de Lisboa (ISCTE-IUL), ISTAR-IUL, Av. das Forças Armadas, Lisboa 1649-026, Portugal
| | - António M Mendes
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, Lisboa 1649-028, Portugal
| | - Pedro G Lind
- Instituto Universitário de Lisboa (ISCTE-IUL), ISTAR-IUL, Av. das Forças Armadas, Lisboa 1649-026, Portugal; Department of Computer Science, OsloMet - Oslo Metropolitan University, P.O. Box 4 St. Olavs plass, Oslo N-0130, Norway.
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Franklinos LHV, Jones KE, Redding DW, Abubakar I. The effect of global change on mosquito-borne disease. THE LANCET. INFECTIOUS DISEASES 2019; 19:e302-e312. [PMID: 31227327 DOI: 10.1016/s1473-3099(19)30161-6] [Citation(s) in RCA: 226] [Impact Index Per Article: 45.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 02/19/2019] [Accepted: 03/21/2019] [Indexed: 01/01/2023]
Abstract
More than 80% of the global population is at risk of a vector-borne disease, with mosquito-borne diseases being the largest contributor to human vector-borne disease burden. Although many global processes, such as land-use and socioeconomic change, are thought to affect mosquito-borne disease dynamics, research to date has strongly focused on the role of climate change. Here, we show, through a review of contemporary modelling studies, that no consensus on how future changes in climatic conditions will impact mosquito-borne diseases exists, possibly due to interacting effects of other global change processes, which are often excluded from analyses. We conclude that research should not focus solely on the role of climate change but instead consider growing evidence for additional factors that modulate disease risk. Furthermore, future research should adopt new technologies, including developments in remote sensing and system dynamics modelling techniques, to enable a better understanding and mitigation of mosquito-borne diseases in a changing world.
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Affiliation(s)
- Lydia H V Franklinos
- Centre for Biodiversity and Environment Research, Division of Biosciences, University College London, London, UK; Institute for Global Health, University College London, London, UK.
| | - Kate E Jones
- Centre for Biodiversity and Environment Research, Division of Biosciences, University College London, London, UK; Institute of Zoology, Zoological Society of London, London, UK
| | - David W Redding
- Centre for Biodiversity and Environment Research, Division of Biosciences, University College London, London, UK
| | - Ibrahim Abubakar
- Institute for Global Health, University College London, London, UK
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56
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Rizzoli A, Tagliapietra V, Cagnacci F, Marini G, Arnoldi D, Rosso F, Rosà R. Parasites and wildlife in a changing world: The vector-host- pathogen interaction as a learning case. Int J Parasitol Parasites Wildl 2019; 9:394-401. [PMID: 31341772 PMCID: PMC6630057 DOI: 10.1016/j.ijppaw.2019.05.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 05/28/2019] [Accepted: 05/29/2019] [Indexed: 02/06/2023]
Abstract
In the Anthropocene context, changes in climate, land use and biodiversity are considered among the most important anthropogenic factors affecting parasites-host interaction and wildlife zoonotic diseases emergence. Transmission of vector borne pathogens are particularly sensitive to these changes due to the complexity of their cycle, where the transmission of a microparasite depends on the interaction between its vector, usually a macroparasite, and its reservoir host, in many cases represented by a wildlife vertebrate. The scope of this paper focuses on the effect of some major, fast-occurring anthropogenic changes on the vectorial capacity for tick and mosquito borne pathogens. Specifically, we review and present the latest advances regarding two emerging vector-borne viruses in Europe: Tick-borne encephalitis virus (TBEV) and West Nile virus (WNV). In both cases, variation in vector to host ratio is critical in determining the intensity of pathogen transmission and consequently infection hazard for humans. Forecasting vector-borne disease hazard under the global change scenarios is particularly challenging, requiring long term studies based on a multidisciplinary approach in a One-Health framework.
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Affiliation(s)
- Annapaola Rizzoli
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010, San Michele all’Adige, Trento, Italy
| | - Valentina Tagliapietra
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010, San Michele all’Adige, Trento, Italy
| | - Francesca Cagnacci
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010, San Michele all’Adige, Trento, Italy
| | - Giovanni Marini
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010, San Michele all’Adige, Trento, Italy
| | - Daniele Arnoldi
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010, San Michele all’Adige, Trento, Italy
| | - Fausta Rosso
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010, San Michele all’Adige, Trento, Italy
| | - Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010, San Michele all’Adige, Trento, Italy
- Centre Agriculture Food Environment, University of Trento, San Michele all’Adige, Trento, Italy
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57
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Hurford A, Wang X, Zhao XQ. Regional climate affects salmon lice dynamics, stage structure and management. Proc Biol Sci 2019; 286:20190428. [PMID: 31185867 DOI: 10.1098/rspb.2019.0428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Regional variation in climate can generate differences in population dynamics and stage structure. Where regional differences exist, the best approach to pest management may be region-specific. Salmon lice are a stage-structured marine copepod that parasitizes salmonids at aquaculture sites worldwide, and have fecundity, development and mortality rates that depend on temperature and salinity. We show that in Atlantic Canada and Norway, where the oceans are relatively cold, salmon lice abundance decreases during the winter months, but ultimately increases from year to year, while in Ireland and Chile, where the oceans are warmer, the population size grows monotonically without any seasonal declines. In colder regions, during the winter the stage structure is dominated by the adult stage, which is in contrast to warmer regions where all stages are abundant year round. These differences translate into region-specific recommendations for management: regions with slower population growth have lower critical stocking densities, and regions with cold winters have a seasonal dependence in the timing of follow-up chemotherapeutic treatments. Predictions of our salmon lice model agree with empirical data, and our approach provides a method to understand the effects of regional differences in climate on salmon lice dynamics and management.
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Affiliation(s)
- Amy Hurford
- 1 Department of Biology, Memorial University , St John's, Newfoundland and Labrador , Canada A1C 5S7.,2 Department of Mathematics and Statistics, Memorial University , St John's, Newfoundland and Labrador , Canada A1C 5S7
| | - Xiunan Wang
- 3 Department of Mathematical and Statistical Sciences, University of Alberta , Edmonton, Alberta , Canada T6G 2G1
| | - Xiao-Qiang Zhao
- 2 Department of Mathematics and Statistics, Memorial University , St John's, Newfoundland and Labrador , Canada A1C 5S7
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Bartlow AW, Manore C, Xu C, Kaufeld KA, Del Valle S, Ziemann A, Fairchild G, Fair JM. Forecasting Zoonotic Infectious Disease Response to Climate Change: Mosquito Vectors and a Changing Environment. Vet Sci 2019; 6:E40. [PMID: 31064099 PMCID: PMC6632117 DOI: 10.3390/vetsci6020040] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 04/12/2019] [Accepted: 04/29/2019] [Indexed: 12/20/2022] Open
Abstract
Infectious diseases are changing due to the environment and altered interactions among hosts, reservoirs, vectors, and pathogens. This is particularly true for zoonotic diseases that infect humans, agricultural animals, and wildlife. Within the subset of zoonoses, vector-borne pathogens are changing more rapidly with climate change, and have a complex epidemiology, which may allow them to take advantage of a changing environment. Most mosquito-borne infectious diseases are transmitted by mosquitoes in three genera: Aedes, Anopheles, and Culex, and the expansion of these genera is well documented. There is an urgent need to study vector-borne diseases in response to climate change and to produce a generalizable approach capable of generating risk maps and forecasting outbreaks. Here, we provide a strategy for coupling climate and epidemiological models for zoonotic infectious diseases. We discuss the complexity and challenges of data and model fusion, baseline requirements for data, and animal and human population movement. Disease forecasting needs significant investment to build the infrastructure necessary to collect data about the environment, vectors, and hosts at all spatial and temporal resolutions. These investments can contribute to building a modeling community around the globe to support public health officials so as to reduce disease burden through forecasts with quantified uncertainty.
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Affiliation(s)
- Andrew W Bartlow
- Los Alamos National Laboratory, Biosecurity and Public Health, Los Alamos, NM 87545, USA.
| | - Carrie Manore
- Los Alamos National Laboratory, Information Systems and Modeling, Los Alamos, NM 87545, USA.
| | - Chonggang Xu
- Los Alamos National Laboratory, Earth Systems Observations, Los Alamos, NM 87545, USA.
| | - Kimberly A Kaufeld
- Los Alamos National Laboratory, Statistical Sciences, Los Alamos, NM 87545, USA.
| | - Sara Del Valle
- Los Alamos National Laboratory, Information Systems and Modeling, Los Alamos, NM 87545, USA.
| | - Amanda Ziemann
- Los Alamos National Laboratory, Space Data Science and Systems, Los Alamos, NM 87545, USA.
| | - Geoffrey Fairchild
- Los Alamos National Laboratory, Information Systems and Modeling, Los Alamos, NM 87545, USA.
| | - Jeanne M Fair
- Los Alamos National Laboratory, Biosecurity and Public Health, Los Alamos, NM 87545, USA.
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Krol L, Gorsich EE, Hunting ER, Govender D, van Bodegom PM, Schrama M. Eutrophication governs predator-prey interactions and temperature effects in Aedes aegypti populations. Parasit Vectors 2019; 12:179. [PMID: 31014388 PMCID: PMC6480876 DOI: 10.1186/s13071-019-3431-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 04/04/2019] [Indexed: 12/04/2022] Open
Abstract
Background Mosquito population dynamics are driven by large-scale (e.g. climatological) and small-scale (e.g. ecological) factors. While these factors are known to independently influence mosquito populations, it remains uncertain how drivers that simultaneously operate under natural conditions interact to influence mosquito populations. We, therefore, developed a well-controlled outdoor experiment to assess the interactive effects of two ecological drivers, predation and nutrient availability, on mosquito life history traits under multiple temperature regimes. Methods We conducted a temperature-controlled mesocosm experiment in Kruger National Park, South Africa, with the yellow fever mosquito, Aedes aegypti. We investigated how larval survival, emergence and development rates were impacted by the presence of a locally-common invertebrate predator (backswimmers Anisops varia Fieber (Notonectidae: Hemiptera), nutrient availability (oligotrophic vs eutrophic, reflecting field conditions), water temperature, and interactions between each driver. Results We observed that the effects of predation and temperature both depended on eutrophication. Predation caused lower adult emergence in oligotrophic conditions but higher emergence under eutrophic conditions. Higher temperatures caused faster larval development rates in eutrophic but not oligotrophic conditions. Conclusions Our study shows that ecological bottom-up and top-down drivers strongly and interactively govern mosquito life history traits for Ae. aegypti populations. Specifically, we show that eutrophication can inversely affect predator–prey interactions and mediate the effect of temperature on mosquito survival and development rates. Hence, our results suggest that nutrient pollution can overrule biological constraints on natural mosquito populations and highlights the importance of studying multiple factors. Electronic supplementary material The online version of this article (10.1186/s13071-019-3431-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Louie Krol
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands.,Naturalis Biodiversity Centre, Leiden, The Netherlands
| | - Erin E Gorsich
- The Zeeman Institute for Systems Biology & Infectious Disease Epidemiology Research, University of Warwick, Coventry, UK.,School of Life Sciences, University of Warwick, Coventry, UK
| | - Ellard R Hunting
- School of Biological Sciences, University of Bristol, Bristol, UK.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Danny Govender
- Department of Paraclinical Sciences, University of Pretoria, Pretoria, South Africa.,Scientific Services Kruger National Park, Skukuza, South Africa
| | - Peter M van Bodegom
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands
| | - Maarten Schrama
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands. .,Naturalis Biodiversity Centre, Leiden, The Netherlands.
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60
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Lou Y, Liu K, He D, Gao D, Ruan S. Modelling diapause in mosquito population growth. J Math Biol 2019; 78:2259-2288. [DOI: 10.1007/s00285-019-01343-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 08/30/2018] [Indexed: 11/30/2022]
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61
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Ewing DA, Purse BV, Cobbold CA, Schäfer SM, White SM. Uncovering mechanisms behind mosquito seasonality by integrating mathematical models and daily empirical population data: Culex pipiens in the UK. Parasit Vectors 2019; 12:74. [PMID: 30732629 PMCID: PMC6367758 DOI: 10.1186/s13071-019-3321-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 01/28/2019] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Many mosquito-borne diseases exhibit substantial seasonality, due to strong links between environmental variables and vector and pathogen life-cycles. Further, a range of density-dependent and density-independent biotic and abiotic processes affect the phenology of mosquito populations, with potentially large knock-on effects for vector dynamics and disease transmission. Whilst it is understood that density-independent and density-dependent processes affect seasonal population levels, it is not clear how these interact temporally to shape the population peaks and troughs. Due to this, the paucity of high-resolution data for validation, and the difficulty of parameterizing density-dependent processes, models of vector dynamics may poorly estimate abundances, which has knock-on effects for our ability predict vector-borne disease outbreaks. RESULTS We present a rich dataset describing seasonal abundance patterns of each life stage of Culex pipiens, a widespread vector of West Nile virus, at a field site in southern England in 2015. Abundance of immature stages was measured three times per week, whilst adult traps were run four nights each week. This dataset is integrated with an existing delay-differential equation model predicting Cx. pipiens seasonal abundance to improve understanding of observed seasonal abundance patterns. At our field site, the outcome of our model fitting suggests interspecific predation on mosquito larvae and temperature-dependent larval mortality combine to act as the main sources of population regulation throughout the active season, whilst competition for resources is a relatively small source of larval mortality. CONCLUSIONS The model suggests that density-independent mortality and interspecific predation interact to shape patterns of mosquito seasonal abundance in a permanent aquatic habitat and we propose that competition for resources is likely to be important where periods of high rainfall create transient habitats. Further, we highlight the importance of challenging population abundance models with data from across all life stages of the species of interest if reliable inferences are to be drawn from these models, particularly when considering mosquito control and vector-borne disease transmission.
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Affiliation(s)
- David A. Ewing
- Centre for Ecology & Hydrology, Benson Lane, Crowmarsh Gifford, Wallingford, OX10 8BB UK
- Department of Mathematics and Statistics, University of Glasgow, University Place, Glasgow, G12 8QQ UK
- Present address: Biomathematics and Statistics Scotland, James Clerk Maxwell Building, Peter Guthrie Tate Road, The King’s Buildings, Edinburgh, EH9 3FD UK
| | - Bethan V. Purse
- Centre for Ecology & Hydrology, Benson Lane, Crowmarsh Gifford, Wallingford, OX10 8BB UK
| | - Christina A. Cobbold
- Department of Mathematics and Statistics, University of Glasgow, University Place, Glasgow, G12 8QQ UK
- The Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, University Avenue, Glasgow, G12 8QQ UK
| | - Stefanie M. Schäfer
- Centre for Ecology & Hydrology, Benson Lane, Crowmarsh Gifford, Wallingford, OX10 8BB UK
| | - Steven M. White
- Centre for Ecology & Hydrology, Benson Lane, Crowmarsh Gifford, Wallingford, OX10 8BB UK
- The Wolfson Centre for Mathematical Biology, Mathematical Institute, Radcliffe Observatory Quarter, Woodstock Road, Oxford, OX2 6GG UK
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62
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Mukhtar AYA, Munyakazi JB, Ouifki R. Assessing the role of climate factors on malaria transmission dynamics in South Sudan. Math Biosci 2019; 310:13-23. [PMID: 30711479 DOI: 10.1016/j.mbs.2019.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 10/04/2018] [Accepted: 01/11/2019] [Indexed: 01/16/2023]
Abstract
Malaria is endemic in South Sudan and it is one of the most severe diseases in the war-torn nation. There has been much concern about whether the severity of its transmission might depend upon climatic conditions that are related to the reproduction of the single-cell parasite attaching to female mosquitoes, especially in high altitude areas. The country experiences two different climatic conditions; namely one tropical and the other hot and semi-arid. In this study, we aim to assess the potential impact of climatic conditions on malaria prevalence in these two climatically distinct regions of South Sudan. We develop and analyze a host-mosquito disease-based model that includes temperature and rainfall. The model has also been parameterized in a Bayesian framework using Bayesian Markov Chain Monte Carlo (MCMC). The mathematical analysis for this study has included equilibria, stability and a sensitivity index on the basic reproduction number R0. The threshold R0 is also used to provide a numerical basis for further refinement and prediction of the impact of climate variability on malaria transmission intensity over the study region. The study highlights the impact of various temperature values on the population dynamics of the mosquito.
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Affiliation(s)
- Abdulaziz Y A Mukhtar
- Department of Mathematics and Applied Mathematics, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa; DST-NRF Centre of Excellence in Mathematical and Statistical Sciences (CoE-Mass), South Africa.
| | - Justin B Munyakazi
- Department of Mathematics and Applied Mathematics, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Rachid Ouifki
- Department of Mathematics and Applied Mathematics, Faculty of Natural & Agricultural Sciences, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
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63
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Bakary T, Boureima S, Sado T. A mathematical model of malaria transmission in a periodic environment. JOURNAL OF BIOLOGICAL DYNAMICS 2018; 12:400-432. [PMID: 29730976 DOI: 10.1080/17513758.2018.1468935] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 04/13/2018] [Indexed: 06/08/2023]
Abstract
In this paper, we present a mathematical model of malaria transmission dynamics with age structure for the vector population and a periodic biting rate of female anopheles mosquitoes. The human population is divided into two major categories: the most vulnerable called non-immune and the least vulnerable called semi-immune. By applying the theory of uniform persistence and the Floquet theory with comparison principle, we analyse the stability of the disease-free equilibrium and the behaviour of the model when the basic reproduction ratio [Formula: see text] is greater than one or less than one. At last, numerical simulations are carried out to illustrate our mathematical results.
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Affiliation(s)
- Traoré Bakary
- a Department of Mathematics (UFR/ST) , Polytechnic University of Bobo-Dioulasso , Bobo-Dioulasso , Burkina Faso
| | - Sangaré Boureima
- a Department of Mathematics (UFR/ST) , Polytechnic University of Bobo-Dioulasso , Bobo-Dioulasso , Burkina Faso
| | - Traoré Sado
- a Department of Mathematics (UFR/ST) , Polytechnic University of Bobo-Dioulasso , Bobo-Dioulasso , Burkina Faso
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64
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Huang CC, Tam TYT, Chern YR, Lung SCC, Chen NT, Wu CD. Spatial Clustering of Dengue Fever Incidence and Its Association with Surrounding Greenness. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:E1869. [PMID: 30158475 PMCID: PMC6163306 DOI: 10.3390/ijerph15091869] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 08/21/2018] [Accepted: 08/27/2018] [Indexed: 11/25/2022]
Abstract
With more than 58,000 cases reported by the country's Centers for Disease Control, the dengue outbreaks from 2014 to 2015 seriously impacted the southern part of Taiwan. This study aims to assess the spatial autocorrelation of the dengue fever (DF) outbreak in southern Taiwan in 2014 and 2015, and to further understand the effects of green space (such as forests, farms, grass, and parks) allocation on DF. In this study, two different greenness indexes were used. The first green metric, the normalized difference vegetation index (NDVI), was provided by the long-term NASA MODIS satellite NDVI database, which quantifies and represents the overall vegetation greenness. The latest 2013 land use survey GIS database completed by the National Land Surveying and Mapping Center was obtained to access another green metric, green land use in Taiwan. We first used Spearman's rho to find out the relationship between DF and green space, and then three spatial autocorrelation methods, including Global Moran's I, high/low clustering, and Hot Spot were employed to assess the spatial autocorrelation of DF outbreak. In considering the impact of social and environmental factors in DF, we used generalized linear mixed models (GLMM) to further clarify the relationship between different types of green land use and dengue cases. Results of spatial autocorrelation analysis showed a high aggregation of dengue epidemic in southern Taiwan, and the metropolitan areas were the main hotspots. Results of correlation analysis and GLMM showed a positive correlation between parks and dengue fever, and the other five green space metrics and land types revealed a negative association with DF. Our findings may be an important asset for improving surveillance and control interventions for dengue.
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Affiliation(s)
- Chi-Chieh Huang
- Department of Forestry and Natural Resources, National Chiayi University, Chiayi 60004, Taiwan.
| | - Tuen Yee Tiffany Tam
- Department of Forestry and Natural Resources, National Chiayi University, Chiayi 60004, Taiwan.
| | - Yinq-Rong Chern
- Department of Forestry and Natural Resources, National Chiayi University, Chiayi 60004, Taiwan.
| | - Shih-Chun Candice Lung
- Research Center for Environmental Changes, Academia Sinica, Taipei 11529, Taiwan.
- Department of Atmospheric Sciences, National Taiwan University, Taipei 10617, Taiwan.
- Institute of Environmental Health, National Taiwan University, Taipei 10055, Taiwan.
| | - Nai-Tzu Chen
- National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli 35053, Taiwan.
| | - Chih-Da Wu
- Department of Geomatics, National Cheng Kung University, Tainan 70101, Taiwan.
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65
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Modeling the 2013 Zika Outbreak in French Polynesia: Intervention Strategies. APPLIED SYSTEM INNOVATION 2018. [DOI: 10.3390/asi1030031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The ongoing Zika virus (ZIKV) in the Americas has been a serious public health emergency since 2015. Since Zika is a vector-borne disease, the size of the vector population in the affected area plays a key role in controlling the scale of the outbreak. The primary vectors for Zika, the Aedes Agypti and Aedes Albopictus species of mosquitoes, are highly sensitive to climatic conditions for survival and reproduction. Additionally, increased international travel over the years has caused the disease outbreak to turn into a pandemic affecting five continents. The mosquito population and the human travel patterns are the two main driving forces affecting the persistence and resurgence of Zika and other vector-borne diseases. This paper presents an enhanced dynamic model that simulates the 2013–2014 French Polynesia Zika outbreak incorporating the temperature dependent mosquito ecology and the local transit network (flights and ferries). The study highlights the importance of human travel patterns and mosquito population dynamics in a disease outbreak. The results predict that more than 85% of the population was infected by the end of the outbreak and it lasted for more than five months across the islands. The basic reproduction number ( R 0 ) for the outbreak is also calculated using the next-generation-matrix for validation purposes. Additionally, this study is focused on measuring the impact of intervention strategies like reducing the mosquito population, preventing mosquito bites and imposing travel bans. French Polynesia was chosen as the region of interest for the study because of available demographic, climate and transit data. Additionally, results from similar studies for the region are available for validation and comparison. However, the proposed system can be used to study the transmission dynamics of any vector-borne disease in any geographic region by altering the climatic and demographic data, and the transit network.
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66
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Culler LE, Ayres MP, Virginia RA. Spatial heterogeneity in the abundance and fecundity of Arctic mosquitoes. Ecosphere 2018. [DOI: 10.1002/ecs2.2345] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Lauren E. Culler
- Environmental Studies Program Dartmouth College 113 Steele Hall Hanover New Hampshire 03755 USA
- Institute of Arctic Studies The Dickey Center for International Understanding Dartmouth College 6214 Haldeman Center Hanover New Hampshire 03755 USA
- Department of Biological Sciences Dartmouth College 78 College Street Hanover New Hampshire 03755 USA
| | - Matthew P. Ayres
- Institute of Arctic Studies The Dickey Center for International Understanding Dartmouth College 6214 Haldeman Center Hanover New Hampshire 03755 USA
- Department of Biological Sciences Dartmouth College 78 College Street Hanover New Hampshire 03755 USA
| | - Ross A. Virginia
- Environmental Studies Program Dartmouth College 113 Steele Hall Hanover New Hampshire 03755 USA
- Institute of Arctic Studies The Dickey Center for International Understanding Dartmouth College 6214 Haldeman Center Hanover New Hampshire 03755 USA
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67
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A mathematical model for Zika virus transmission dynamics with a time-dependent mosquito biting rate. Theor Biol Med Model 2018; 15:11. [PMID: 30064447 PMCID: PMC6069545 DOI: 10.1186/s12976-018-0083-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/04/2018] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Mathematical modeling has become a tool used to address many emerging diseases. One of the most basic and popular modeling frameworks is the compartmental model. Unfortunately, most of the available compartmental models developed for Zika virus (ZIKV) transmission were designed to describe and reconstruct only past, short-time ZIKV outbreaks in which the effects of seasonal change to entomological parameters can be ignored. To make an accurate long-term prediction of ZIKV transmission, the inclusion of seasonal effects into an epidemic model is unavoidable. METHODS We developed a vector-borne compartmental model to analyze the spread of the ZIKV during the 2015-2016 outbreaks in Bahia, Brazil and to investigate the impact of two vector control strategies, namely, reducing mosquito biting rates and reducing mosquito population size. The model considered the influences of seasonal change on the ZIKV transmission dynamics via the time-varying mosquito biting rate. The model was also validated by comparing the model prediction with reported data that were not used to calibrate the model. RESULTS We found that the model can give a very good fit between the simulation results and the reported Zika cases in Bahia (R-square = 0.9989). At the end of 2016, the total number of ZIKV infected people was predicted to be 1.2087 million. The model also predicted that there would not be a large outbreak from May 2016 to December 2016 due to the decrease of the susceptible pool. Implementing disease mitigation by reducing the mosquito biting rates was found to be more effective than reducing the mosquito population size. Finally, the correlation between the time series of estimated mosquito biting rates and the average temperature was also suggested. CONCLUSIONS The proposed ZIKV transmission model together with the estimated weekly biting rates can reconstruct the past long-time multi-peak ZIKV outbreaks in Bahia.
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68
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Lee H, Kim JE, Lee S, Lee CH. Potential effects of climate change on dengue transmission dynamics in Korea. PLoS One 2018; 13:e0199205. [PMID: 29953493 PMCID: PMC6023222 DOI: 10.1371/journal.pone.0199205] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/04/2018] [Indexed: 11/22/2022] Open
Abstract
Dengue fever is a major international public health concern, with more than 55% of the world population at risk of infection. Recent climate changes related to global warming have increased the potential risk of domestic outbreaks of dengue in Korea. In this study, we develop a two-strain dengue model associated with climate-dependent parameters based on Representative Concentration Pathway (RCP) scenarios provided by the Korea Meteorological Administration. We assess the potential risks of dengue outbreaks by means of the vector capacity and intensity under various RCP scenarios. A sensitivity analysis of the temperature-dependent parameters is performed to explore the effects of climate change on dengue transmission dynamics. Our results demonstrate that a higher temperature significantly enhances the potential threat of domestic dengue outbreaks in Korea. Furthermore, we investigate the effects of countermeasures on the cumulative incidence of humans and vectors. The current main control measures (comprising only travel restrictions) for infected humans in Korea are not as effective as combined control measures (travel restrictions and vector control), dramatically reducing the possibilities of dengue outbreaks.
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Affiliation(s)
- Hyojung Lee
- Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Jung Eun Kim
- Department of Mathematical Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Sunmi Lee
- Department of Applied Mathematics, Kyung Hee University, Yongin, Republic of Korea
| | - Chang Hyeong Lee
- Department of Mathematical Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
- * E-mail:
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69
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Pfab F, Stacconi MVR, Anfora G, Grassi A, Walton V, Pugliese A. Optimized timing of parasitoid release: a mathematical model for biological control of Drosophila suzukii. THEOR ECOL-NETH 2018. [DOI: 10.1007/s12080-018-0382-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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70
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Threshold Dynamics of a Temperature-Dependent Stage-Structured Mosquito Population Model with Nested Delays. Bull Math Biol 2018; 80:1962-1987. [DOI: 10.1007/s11538-018-0447-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/14/2018] [Indexed: 10/16/2022]
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71
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Yu D, Madras N, Zhu H. Temperature-driven population abundance model for Culex pipiens and Culex restuans (Diptera: Culicidae). J Theor Biol 2018; 443:28-38. [PMID: 29366824 DOI: 10.1016/j.jtbi.2018.01.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/17/2018] [Accepted: 01/18/2018] [Indexed: 10/18/2022]
Abstract
We develop a temperature-driven abundance model for West Nile virus (WNV) vector species, Culex pipiens and Culex restuans. Temperature-dependent response functions for mosquito development, mortality, and diapause were formulated based on results from available laboratory and field studies. Numerical results compared to observed mosquito trap counts from 2004-2016 demonstrate the ability of our model to predict the observed trend of the mosquito population over a single season in the Peel Region, Ontario. The model has potential to be used as a real-time mosquito abundance forecasting tool with applications in mosquito control programs.
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Affiliation(s)
- Don Yu
- Department of Mathematics and Statistics, York University, Toronto, ON, Canada; Laboratory of Mathematical Parallel Systems, York University, Toronto, ON, Canada
| | - Neal Madras
- Department of Mathematics and Statistics, York University, Toronto, ON, Canada; Laboratory of Mathematical Parallel Systems, York University, Toronto, ON, Canada
| | - Huaiping Zhu
- Department of Mathematics and Statistics, York University, Toronto, ON, Canada; Laboratory of Mathematical Parallel Systems, York University, Toronto, ON, Canada.
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72
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Paull SH, Horton DE, Ashfaq M, Rastogi D, Kramer LD, Diffenbaugh NS, Kilpatrick AM. Drought and immunity determine the intensity of West Nile virus epidemics and climate change impacts. Proc Biol Sci 2018; 284:rspb.2016.2078. [PMID: 28179512 DOI: 10.1098/rspb.2016.2078] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 01/12/2017] [Indexed: 11/12/2022] Open
Abstract
The effect of global climate change on infectious disease remains hotly debated because multiple extrinsic and intrinsic drivers interact to influence transmission dynamics in nonlinear ways. The dominant drivers of widespread pathogens, like West Nile virus, can be challenging to identify due to regional variability in vector and host ecology, with past studies producing disparate findings. Here, we used analyses at national and state scales to examine a suite of climatic and intrinsic drivers of continental-scale West Nile virus epidemics, including an empirically derived mechanistic relationship between temperature and transmission potential that accounts for spatial variability in vectors. We found that drought was the primary climatic driver of increased West Nile virus epidemics, rather than within-season or winter temperatures, or precipitation independently. Local-scale data from one region suggested drought increased epidemics via changes in mosquito infection prevalence rather than mosquito abundance. In addition, human acquired immunity following regional epidemics limited subsequent transmission in many states. We show that over the next 30 years, increased drought severity from climate change could triple West Nile virus cases, but only in regions with low human immunity. These results illustrate how changes in drought severity can alter the transmission dynamics of vector-borne diseases.
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Affiliation(s)
- Sara H Paull
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, 1156 High St, Santa Cruz, CA 95064, USA .,Research Applications Lab, National Center for Atmospheric Research, 3450 Mitchell Ln, Boulder, CO 80301, USA
| | - Daniel E Horton
- Department of Earth and Planetary Sciences, Northwestern University, Evanston, IL 60208, USA.,Department of Earth System Science and Woods Institute for the Environment, Stanford University, Stanford, CA 94305, USA
| | - Moetasim Ashfaq
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Deeksha Rastogi
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Laura D Kramer
- Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA.,School of Public Health, Department of Biomedical Sciences, SUNY, Albany, NY 12201, USA
| | - Noah S Diffenbaugh
- Department of Earth System Science and Woods Institute for the Environment, Stanford University, Stanford, CA 94305, USA
| | - A Marm Kilpatrick
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, 1156 High St, Santa Cruz, CA 95064, USA
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73
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Ferris C, Best A. The evolution of host defence to parasitism in fluctuating environments. J Theor Biol 2017; 440:58-65. [PMID: 29221891 DOI: 10.1016/j.jtbi.2017.12.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 11/08/2017] [Accepted: 12/04/2017] [Indexed: 11/30/2022]
Abstract
Given rapidly changing environments, it is important for us to understand how the evolution of host defence responds to fluctuating environments. Here we present the first theoretical study of evolution of host resistance to parasitism in a classic epidemiological model where the host birth rate varies seasonally. We show that this form of seasonality has clear qualitative and quantitative impacts on the evolution of resistance. When the host can recover from infection, it evolves a lower level of defence when the amplitude is high. However, when recovery is absent, the host increases its defence for higher amplitudes. Between these different behaviours we find a region of parameter space that allows evolutionary bistability. When this occurs, the level of defence the host evolves depends on initial conditions, and in some cases a switch between attractors can lead to different periods in the population dynamics at each of the evolutionary stable strategies. Crucially, we find that evolutionary behaviour found in a constant environment for this model doesn't always hold for hosts with highly variable birth rates. Hence we argue that seasonality must be taken into account if we want to make predictions about evolutionary trends in real-world host-parasite systems.
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Affiliation(s)
- Charlotte Ferris
- School of Mathematics and Statistics, University of Sheffield, Sheffield, S3 7RH, UK.
| | - Alex Best
- School of Mathematics and Statistics, University of Sheffield, Sheffield, S3 7RH, UK
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74
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Bai Z, Peng R, Zhao XQ. A reaction–diffusion malaria model with seasonality and incubation period. J Math Biol 2017; 77:201-228. [DOI: 10.1007/s00285-017-1193-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 08/23/2017] [Indexed: 10/18/2022]
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75
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Otto A, Wang J, Radons G. Delay-induced wave instabilities in single-species reaction-diffusion systems. Phys Rev E 2017; 96:052202. [PMID: 29347731 DOI: 10.1103/physreve.96.052202] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Indexed: 11/07/2022]
Abstract
The Turing (wave) instability is only possible in reaction-diffusion systems with more than one (two) components. Motivated by the fact that a time delay increases the dimension of a system, we investigate the presence of diffusion-driven instabilities in single-species reaction-diffusion systems with delay. The stability of arbitrary one-component systems with a single discrete delay, with distributed delay, or with a variable delay is systematically analyzed. We show that a wave instability can appear from an equilibrium of single-species reaction-diffusion systems with fluctuating or distributed delay, which is not possible in similar systems with constant discrete delay or without delay. More precisely, we show by basic analytic arguments and by numerical simulations that fast asymmetric delay fluctuations or asymmetrically distributed delays can lead to wave instabilities in these systems. Examples, for the resulting traveling waves are shown for a Fisher-KPP equation with distributed delay in the reaction term. In addition, we have studied diffusion-induced instabilities from homogeneous periodic orbits in the same systems with variable delay, where the homogeneous periodic orbits are attracting resonant periodic solutions of the system without diffusion, i.e., periodic orbits of the Hutchinson equation with time-varying delay. If diffusion is introduced, standing waves can emerge whose temporal period is equal to the period of the variable delay.
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Affiliation(s)
- Andereas Otto
- Institute of Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany
| | - Jian Wang
- Institute of Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany
| | - Günter Radons
- Institute of Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany
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76
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Surges in trematode prevalence linked to centennial-scale flooding events in the Adriatic. Sci Rep 2017; 7:5732. [PMID: 28720866 PMCID: PMC5516012 DOI: 10.1038/s41598-017-05979-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 05/31/2017] [Indexed: 11/30/2022] Open
Abstract
The forecasts of increasing global temperature and sea level rise have led to concern about the response of parasites to anthropogenic climate change. Whereas ecological studies of parasite response to environmental shifts are necessarily limited to short time scales, the fossil record can potentially provide a quantitative archive of long-term ecological responses to past climate transitions. Here, we document multi-centennial scale changes in prevalence of trematodes infesting the bivalve host Abra segmentum through multiple sea-level fluctuations preserved in brackish Holocene deposits of the Po Plain, Italy. Prevalence values were significantly elevated (p < 0.01) in samples associated with flooding surfaces, yet the temporal trends of parasite prevalence and host shell length, cannot be explained by Waltherian facies change, host availability, salinity, diversity, turnover, or community structure. The observed surges in parasite prevalence during past flooding events indicate that the ongoing global warming and sea-level rise will lead to significant intensification of trematode parasitism, suppressed fecundity of common benthic organisms, and negative impacts on marine ecosystems, ecosystem services, and, eventually, to human well-being.
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77
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Nasrinpour HR, Reimer AA, Friesen MR, McLeod RD. Data Preparation for West Nile Virus Agent-Based Modelling: Protocol for Processing Bird Population Estimates and Incorporating ArcMap in AnyLogic. JMIR Res Protoc 2017; 6:e138. [PMID: 28716770 PMCID: PMC5537560 DOI: 10.2196/resprot.6213] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 10/12/2016] [Accepted: 06/05/2017] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND West Nile Virus (WNV) was first isolated in 1937. Since the 1950s, many outbreaks have occurred in various countries. The first appearance of infected birds in Manitoba, Canada was in 2002. OBJECTIVE This paper describes the data preparation phase of setting up a geographic information system (GIS) simulation environment for WNV Agent-Based Modelling in Manitoba. METHODS The main technology used in this protocol is based on AnyLogic and ArcGIS software. A diverse variety of topics and techniques regarding the data collection phase are presented, as modelling WNV has many disparate attributes, including landscape and weather impacts on mosquito population dynamics and birds' roosting locations, population count, and movement patterns. RESULTS Different maps were combined to create a grid land cover map of Manitoba, Canada in a shapefile format compatible with AnyLogic, in order to modulate mosquito parameters. A significant amount of data regarding 152 bird species, along with their population estimates and locations in Manitoba, were gathered and assembled. Municipality shapefile maps were converted to built-in AnyLogic GIS regions for better compatibility with census data and initial placement of human agents. Accessing shapefiles and their databases in AnyLogic are also discussed. CONCLUSIONS AnyLogic simulation software in combination with Esri ArcGIS provides a powerful toolbox for developers and modellers to simulate almost any GIS-based environment or process. This research should be useful to others working on a variety of mosquito-borne diseases (eg, Zika, dengue, and chikungunya) by demonstrating the importance of data relating to Manitoba and/or introducing procedures to compile such data.
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Affiliation(s)
- Hamid Reza Nasrinpour
- University of Manitoba, Electrical and Computer Engineering Department, Winnipeg, MB, Canada
| | - Alexander A Reimer
- University of Manitoba, Electrical and Computer Engineering Department, Winnipeg, MB, Canada
| | - Marcia R Friesen
- University of Manitoba, Electrical and Computer Engineering Department, Winnipeg, MB, Canada
| | - Robert D McLeod
- University of Manitoba, Electrical and Computer Engineering Department, Winnipeg, MB, Canada
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Newman CM, Krebs BL, Anderson TK, Hamer GL, Ruiz MO, Brawn JD, Brown WM, Kitron UD, Goldberg TL. Culex Flavivirus During West Nile Virus Epidemic and Interepidemic Years in Chicago, United States. Vector Borne Zoonotic Dis 2017. [PMID: 28628366 DOI: 10.1089/vbz.2017.2124] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Culex flavivirus (CxFV) is an insect-specific flavivirus infecting Culex mosquitoes, which are important vectors of West Nile virus (WNV). CxFV and WNV cocirculate in nature and coinfect Culex mosquitoes, including in a WNV "hotspot" in suburban Chicago. We previously identified a positive association between CxFV and WNV in mosquito pools collected from suburban Chicago in 2006. To further investigate this phenomenon, we compared the spatial and temporal distribution of CxFV during an interepidemic year (2011) and an epidemic year (2012) for WNV. Both viruses were more prevalent in mosquito pools in 2012 compared to 2011. During both years, the CxFV infection status of mosquito pools was associated with environmental factors such as habitat type and precipitation frequency rather than coinfection with WNV. These results support the idea that WNV and CxFV are ecologically associated, perhaps because both viruses respond to similar environmental drivers of mosquito populations.
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Affiliation(s)
- Christina M Newman
- 1 Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin-Madison , Madison, Wisconsin
| | | | - Tavis K Anderson
- 3 Virus and Prion Research Unit, National Animal Disease Center , USDA-ARS, Ames, Iowa
| | - Gabriel L Hamer
- 4 Department of Entomology, Texas A&M University , College Station, Texas
| | - Marilyn O Ruiz
- 5 Department of Pathobiology, University of Illinois , Urbana, Illinois
| | - Jeffrey D Brawn
- 6 Department of Natural Resources and Environmental Sciences, University of Illinois , Urbana, Illinois
| | - William M Brown
- 5 Department of Pathobiology, University of Illinois , Urbana, Illinois
| | - Uriel D Kitron
- 7 Department of Environmental Sciences, Emory University , Atlanta, Georgia
| | - Tony L Goldberg
- 8 Department of Pathobiological Sciences, University of Wisconsin-Madison , Madison, Wisconsin
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79
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Molnár PK, Sckrabulis JP, Altman KA, Raffel TR. Thermal Performance Curves and the Metabolic Theory of Ecology-A Practical Guide to Models and Experiments for Parasitologists. J Parasitol 2017; 103:423-439. [PMID: 28604284 DOI: 10.1645/16-148] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Climate change will affect host-parasite dynamics in complex ways. The development of forecast models is necessary for proactive disease management, but past studies have frequently reported thermal performance data in idiosyncratic ways that have limited use for parameterizing thermal host-parasite models. Development of improved forecast models will require strong collaborations between experimental parasitologists and disease modelers. The purpose of this article is to facilitate such collaborations by reviewing practical considerations for describing thermal performance curves of parasite and host performance traits, and using them to predict climate change impacts on host-parasite systems. In the first section, we provide an overview of how thermal performance curves can be embedded in life-cycle-based dynamical models of parasitism, and we outline how such models can capture the net effect of multiple nonlinear temperature dependencies affecting the host-parasite dynamics. We also discuss how macroecological generalities based on the metabolic theory of ecology (MTE) can be used to determine a priori parameter estimates for thermal performance curves to derive null models for data-deficient species, but we note that most of the generalities suggested by MTE remain to be tested for parasites. In the second section, we discuss empirical knowledge gaps for the temperature dependence of parasite and host performance traits, and we outline the types of data that need to be collected to inform MTE-based models for data-deficient species. We specifically emphasize the importance of (1) capturing the entire thermal response of performance traits, including lower and upper temperature thresholds, and (2) experimentally or statistically separating out the thermal responses of different performance traits (e.g., development and mortality) rather than only reporting composite measures (e.g., apparent development). Not adhering to these principles can lead to biased climate change impact predictions. In the third section, we provide a practical guide outlining how experimentalists can contribute to fill data gaps by measuring the temperature dependence of host and parasite performance traits in ways that are systematic, statistically rigorous, and consistent with the requirements of life cycle-based host-parasite models. This guide includes recommendations and practical examples illustrating (1) the use of perturbation analyses to determine experimental priorities, (2) experimental design tips for quantifying thermal response curves, and (3) statistical methods for estimating the parameters of thermal performance curves. Our hope is that this article helps researchers to maximize the value and use of future data collections for both empirical and modelling studies investigating the way in which temperature influences parasitism.
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Affiliation(s)
- Péter K Molnár
- Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada
| | - Jason P Sckrabulis
- Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada
| | - Karie A Altman
- Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada
| | - Thomas R Raffel
- Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada
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80
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Watanabe K, Fukui S, Ohta S. Population of the temperate mosquito, Culex pipiens, decreases in response to habitat climatological changes in future. GEOHEALTH 2017; 1:196-210. [PMID: 32158987 PMCID: PMC7007082 DOI: 10.1002/2017gh000054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 04/26/2017] [Accepted: 05/01/2017] [Indexed: 06/10/2023]
Abstract
Predictions of the temporal distribution of vector mosquitoes are an important issue for human health because the response of mosquito populations to climate change could have implications for the risk of vector-borne diseases. To elucidate the effects of climate change on mosquito populations inhabiting temperate regions, we developed a Physiology-based Climate-driven Mosquito Population model for temperate regions. For accurately reproducing the temporal patterns observed in mosquito populations, the key factors were identified by implementing the combinations of factors into the model. We focused on three factors: the effect of diapause, the positive effect of rainfall on larval carrying capacity, and the negative effect of rainfall as the washout mortality on aquatic stages. For each model, parameters were calibrated using weekly observation data of a Culex pipiens adult population collected in Tokyo, Japan. Based on its likelihood value, the model incorporating diapause, constant carrying capacity, and washout mortality was the best to replicate the observed data. By using the selected model and applying global climate model data, our results indicated that the mosquito population would decrease and adults' active season would be shortened under future climate conditions. We found that incorporating the washout effect in the model settings or not caused a difference in the temporal patterns in the projected mosquito populations. This suggested that water resources in mosquito habitats in temperate regions should be considered for predicting the risk of vector-borne diseases in such regions.
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Affiliation(s)
- K. Watanabe
- Department of Human Behavior and Environment Sciences, Faculty of Human SciencesWaseda UniversityTokorozawaJapan
| | - S. Fukui
- Department of Human Behavior and Environment Sciences, Faculty of Human SciencesWaseda UniversityTokorozawaJapan
| | - S. Ohta
- Department of Human Behavior and Environment Sciences, Faculty of Human SciencesWaseda UniversityTokorozawaJapan
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81
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Zittra C, Vitecek S, Obwaller AG, Rossiter H, Eigner B, Zechmeister T, Waringer J, Fuehrer HP. Landscape structure affects distribution of potential disease vectors (Diptera: Culicidae). Parasit Vectors 2017; 10:205. [PMID: 28441957 PMCID: PMC5405510 DOI: 10.1186/s13071-017-2140-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 04/14/2017] [Indexed: 11/19/2022] Open
Abstract
Background Vector-pathogen dynamics are controlled by fluctuations of potential vector communities, such as the Culicidae. Assessment of mosquito community diversity and, in particular, identification of environmental parameters shaping these communities is therefore of key importance for the design of adequate surveillance approaches. In this study, we assess effects of climatic parameters and habitat structure on mosquito communities in eastern Austria to deliver these highly relevant baseline data. Methods Female mosquitoes were sampled twice a month from April to October 2014 and 2015 at 35 permanent and 23 non-permanent trapping sites using carbon dioxide-baited traps. Differences in spatial and seasonal abundance patterns of Culicidae taxa were identified using likelihood ratio tests; possible effects of environmental parameters on seasonal and spatial mosquito distribution were analysed using multivariate statistical methods. We assessed community responses to environmental parameters based on 14-day-average values that affect ontogenesis. Results Altogether 29,734 female mosquitoes were collected, and 21 of 42 native as well as two of four non-native mosquito species were reconfirmed in eastern Austria. Statistical analyses revealed significant differences in mosquito abundance between sampling years and provinces. Incidence and abundance patterns were found to be linked to 14-day mean sunshine duration, humidity, water–level maxima and the amount of precipitation. However, land cover classes were found to be the most important factor, effectively assigning both indigenous and non-native mosquito species to various communities, which responded differentially to environmental variables. Conclusions These findings thus underline the significance of non-climatic variables for future mosquito prediction models and the necessity to consider these in mosquito surveillance programmes. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-2140-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Carina Zittra
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Simon Vitecek
- Department of Limnology and Bio-Oceanography, University of Vienna, Vienna, Austria
| | - Adelheid G Obwaller
- Federal Ministry of Defence and Sports, Division of Science, Research and Development, Vienna, Austria
| | | | - Barbara Eigner
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | | | - Johann Waringer
- Department of Limnology and Bio-Oceanography, University of Vienna, Vienna, Austria
| | - Hans-Peter Fuehrer
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria.
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82
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Valdez LD, Sibona GJ, Diaz LA, Contigiani MS, Condat CA. Effects of rainfall on Culex mosquito population dynamics. J Theor Biol 2017; 421:28-38. [PMID: 28351704 DOI: 10.1016/j.jtbi.2017.03.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 02/22/2017] [Accepted: 03/25/2017] [Indexed: 11/25/2022]
Abstract
The dynamics of a mosquito population depends heavily on climatic variables such as temperature and precipitation. Since climate change models predict that global warming will impact on the frequency and intensity of rainfall, it is important to understand how these variables affect the mosquito populations. We present a model of the dynamics of a Culex quinquefasciatus mosquito population that incorporates the effect of rainfall and use it to study the influence of the number of rainy days and the mean monthly precipitation on the maximum yearly abundance of mosquitoes Mmax. Additionally, using a fracturing process, we investigate the influence of the variability in daily rainfall on Mmax. We find that, given a constant value of monthly precipitation, there is an optimum number of rainy days for which Mmax is a maximum. On the other hand, we show that increasing daily rainfall variability reduces the dependence of Mmax on the number of rainy days, leading also to a higher abundance of mosquitoes for the case of low mean monthly precipitation. Finally, we explore the effect of the rainfall in the months preceding the wettest season, and we obtain that a regimen with high precipitations throughout the year and a higher variability tends to advance slightly the time at which the peak mosquito abundance occurs, but could significantly change the total mosquito abundance in a year.
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Affiliation(s)
- L D Valdez
- Facultad de Matemática, Astronomía, Física y Computación, Universidad Nacional de Córdoba; Instituto de Física Enrique Gaviola, CONICET, Ciudad Universitaria, 5000 Córdoba, Argentina.
| | - G J Sibona
- Facultad de Matemática, Astronomía, Física y Computación, Universidad Nacional de Córdoba; Instituto de Física Enrique Gaviola, CONICET, Ciudad Universitaria, 5000 Córdoba, Argentina
| | - L A Diaz
- Instituto de Investigaciones Biológicas y Tecnológicas-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina; Laboratorio de Arbovirus-Instituto de Virología "Dr. J. M. Vanella"-Facultad de Ciencias Médicas-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - M S Contigiani
- Laboratorio de Arbovirus-Instituto de Virología "Dr. J. M. Vanella"-Facultad de Ciencias Médicas-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - C A Condat
- Facultad de Matemática, Astronomía, Física y Computación, Universidad Nacional de Córdoba; Instituto de Física Enrique Gaviola, CONICET, Ciudad Universitaria, 5000 Córdoba, Argentina
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83
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Factors affecting the distribution of haemosporidian parasites within an oceanic island. Int J Parasitol 2017; 47:225-235. [DOI: 10.1016/j.ijpara.2016.11.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 11/28/2016] [Accepted: 11/29/2016] [Indexed: 01/10/2023]
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