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Ragonese IG, Sarkar MR, Hall RJ, Altizer S. Extreme heat reduces host and parasite performance in a butterfly-parasite interaction. Proc Biol Sci 2024; 291:20232305. [PMID: 38228180 DOI: 10.1098/rspb.2023.2305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 12/12/2023] [Indexed: 01/18/2024] Open
Abstract
Environmental temperature fundamentally shapes insect physiology, fitness and interactions with parasites. Differential climate warming effects on host versus parasite biology could exacerbate or inhibit parasite transmission, with far-reaching implications for pollination services, biocontrol and human health. Here, we experimentally test how controlled temperatures influence multiple components of host and parasite fitness in monarch butterflies (Danaus plexippus) and their protozoan parasites Ophryocystis elektroscirrha. Using five constant-temperature treatments spanning 18-34°C, we measured monarch development, survival, size, immune function and parasite infection status and intensity. Monarch size and survival declined sharply at the hottest temperature (34°C), as did infection probability, suggesting that extreme heat decreases both host and parasite performance. The lack of infection at 34°C was not due to greater host immunity or faster host development but could instead reflect the thermal limits of parasite invasion and within-host replication. In the context of ongoing climate change, temperature increases above current thermal maxima could reduce the fitness of both monarchs and their parasites, with lower infection rates potentially balancing negative impacts of extreme heat on future monarch abundance and distribution.
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Affiliation(s)
- Isabella G Ragonese
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
- Center for the Ecology of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Maya R Sarkar
- College of Biological Sciences, University of Minnesota, St Paul, MN 5455, USA
| | - Richard J Hall
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
- Center for the Ecology of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Sonia Altizer
- Odum School of Ecology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
- Center for the Ecology of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
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2
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Santos-Vega M, Lowe R, Anselin L, Desai V, Vaishnav KG, Naik A, Pascual M. Quantifying climatic and socioeconomic drivers of urban malaria in Surat, India: a statistical spatiotemporal modelling study. Lancet Planet Health 2023; 7:e985-e998. [PMID: 38056969 DOI: 10.1016/s2542-5196(23)00249-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 10/11/2023] [Accepted: 10/27/2023] [Indexed: 12/08/2023]
Abstract
BACKGROUND Cities are becoming increasingly important habitats for mosquito vectors of disease. The pronounced heterogeneity of urban landscapes challenges our understanding of the effects of climate and socioeconomic factors on mosquito-borne disease dynamics at different spatiotemporal scales. Here, we quantify the impact of climatic and socioeconomic factors on urban malaria risk, using an extensive dataset in both space and time for reported Plasmodium falciparum cases in the city of Surat, northwest India. METHODS We analysed 10 years of monthly P falciparum cases resolved at three nested spatial resolutions (seven zones, 32 units, and 478 worker units) with a Bayesian hierarchical mixed model that incorporates the effects of population density, poverty, relative humidity, and temperature, in addition to random effects (structured and unstructured). To reduce dimensionality and avoid correlation of covariates, socioeconomic variables from survey data were summarised into main axes of variation using principal component analysis. With model selection, we identified the main drivers of spatiotemporal variation in malaria incidence rates at each of the three spatial resolutions. We also compared observations to model-fitted cases by quantifying the percentage of predictions within five discrete levels of malaria risk. FINDINGS The spatial variation of urban malaria cases was stationary over time, whereby locations with high and low yearly cases remained largely consistent across years. Local socioeconomic variation could be summarised with three principal components accounting for approximately 80% of the variance. The model that incorporated local temperature and relative humidity together with two of these principal components, largely representing population density and poverty, best explained monthly malaria patterns in models formulated at the three different spatial scales. As model resolution increased, the effect size of humidity decreased, whereas those of temperature and the principal component associated with population density increased. Model predictions accurately captured aggregated total monthly cases for the city; in space-time, they more closely matched observations at the intermediate scale, with around 57% of units estimated to fall in the observed category on average across years. The mean absolute error was lower at the intermediate level, showing that this is the best aggregation level to predict the space-time dynamics of malaria incidence rates across the city with the selected model. INTERPRETATION This statistical modelling framework provides a basis for development of a climate-driven early warning system for urban malaria for the units of Surat, including spatially explicit prediction of malaria risk several weeks to months in advance. Results indicate environmental and socioeconomic covariates for which further measurement at high resolution should lead to model improvement. Advanced warning combined with local surveillance and knowledge of disease hotspots within the city could inform targeted intervention as part of urban malaria elimination efforts. FUNDING US National Institutes of Health.
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Affiliation(s)
- Mauricio Santos-Vega
- Departamento de Ciencias Biológicas and Grupo de Investigación en Biología Matemática y Computacional BIOMAC, Universidad de los Andes, Bogotá, Colombia.
| | - Rachel Lowe
- Barcelona Supercomputing Center, Barcelona, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain; Centre on Climate Change & Planetary Health and Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Luc Anselin
- Center for Spatial Data Science, University of Chicago, Chicago, IL, USA
| | - Vikas Desai
- Urban Health and Climate Resilience Center of Excellence (UHCRCE), Surat, India
| | - Keshav G Vaishnav
- Vector Borne Diseases Control Department, Surat Municipal Corporation, Surat, India
| | | | - Mercedes Pascual
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, USA; Department of Biology and Department of Environmental Studies, New York University, NY, USA
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Pathak AK, Shiau JC, Freitas RC, Kyle DE. Blood meals from 'dead-end' vertebrate hosts enhance transmission potential of malaria-infected mosquitoes. One Health 2023; 17:100582. [PMID: 38024285 PMCID: PMC10665158 DOI: 10.1016/j.onehlt.2023.100582] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 06/08/2023] [Accepted: 06/08/2023] [Indexed: 12/01/2023] Open
Abstract
Ingestion of an additional blood meal(s) by a hematophagic insect can accelerate development of several vector-borne parasites and pathogens. Most studies, however, offer blood from the same vertebrate host species as the original challenge (for e.g., human for primary and additional blood meals). Here, we show a second blood meal from bovine and canine hosts can also enhance sporozoite migration in Anopheles stephensi mosquitoes infected with the human- and rodent-restricted Plasmodium falciparum and P. berghei, respectively. The extrinsic incubation period (time to sporozoite appearance in salivary glands) showed more consistent reductions with blood from human and bovine donors than canine blood, although the latter's effect may be confounded by the toxicity, albeit non-specific, associated with the anticoagulant used to collect whole blood from donors. The complex patterns of enhancement highlight the limitations of a laboratory system but are nonetheless reminiscent of parasite host-specificity and mosquito adaptations, and the genetic predisposition of An. stephensi for bovine blood. We suggest that in natural settings, a blood meal from any vertebrate host could accentuate the risk of human infections by P. falciparum: targeting vectors that also feed on animals, via endectocides for instance, may reduce the number of malaria-infected mosquitoes and thus directly lower residual transmission. Since endectocides also benefit animal health, our results underscore the utility of the One Health framework, which postulates that human health and well-being is interconnected with that of animals. We posit this framework will be further validated if our observations also apply to other vector-borne diseases which together are responsible for some of the highest rates of morbidity and mortality in socio-economically disadvantaged populations.
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Affiliation(s)
- Ashutosh K. Pathak
- Department of Infectious Diseases, University of Georgia, Athens, GA 30602, United States of America
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, United States of America
- Center for the Ecology of Infectious Diseases (CEID), University of Georgia, Athens, GA 30602, United States of America
- The SporoCore, CTEGD, University of Georgia, Athens, GA 30602, United States of America
| | - Justine C. Shiau
- Department of Infectious Diseases, University of Georgia, Athens, GA 30602, United States of America
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, United States of America
- Center for the Ecology of Infectious Diseases (CEID), University of Georgia, Athens, GA 30602, United States of America
- The SporoCore, CTEGD, University of Georgia, Athens, GA 30602, United States of America
| | - Rafael C.S. Freitas
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, United States of America
- The SporoCore, CTEGD, University of Georgia, Athens, GA 30602, United States of America
| | - Dennis E. Kyle
- Department of Infectious Diseases, University of Georgia, Athens, GA 30602, United States of America
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, United States of America
- The SporoCore, CTEGD, University of Georgia, Athens, GA 30602, United States of America
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, United States of America
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4
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Brown JJ, Pascual M, Wimberly MC, Johnson LR, Murdock CC. Humidity - The overlooked variable in the thermal biology of mosquito-borne disease. Ecol Lett 2023; 26:1029-1049. [PMID: 37349261 DOI: 10.1111/ele.14228] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 04/05/2023] [Indexed: 06/24/2023]
Abstract
Vector-borne diseases cause significant financial and human loss, with billions of dollars spent on control. Arthropod vectors experience a complex suite of environmental factors that affect fitness, population growth and species interactions across multiple spatial and temporal scales. Temperature and water availability are two of the most important abiotic variables influencing their distributions and abundances. While extensive research on temperature exists, the influence of humidity on vector and pathogen parameters affecting disease dynamics are less understood. Humidity is often underemphasized, and when considered, is often treated as independent of temperature even though desiccation likely contributes to declines in trait performance at warmer temperatures. This Perspectives explores how humidity shapes the thermal performance of mosquito-borne pathogen transmission. We summarize what is known about its effects and propose a conceptual model for how temperature and humidity interact to shape the range of temperatures across which mosquitoes persist and achieve high transmission potential. We discuss how failing to account for these interactions hinders efforts to forecast transmission dynamics and respond to epidemics of mosquito-borne infections. We outline future research areas that will ground the effects of humidity on the thermal biology of pathogen transmission in a theoretical and empirical framework to improve spatial and temporal prediction of vector-borne pathogen transmission.
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Affiliation(s)
- Joel J Brown
- Department of Entomology, Cornell University, Ithaca, New York, USA
| | - Mercedes Pascual
- Department of Ecology and Evolution, University of Chicago, Chicago, Illinois, USA
| | - Michael C Wimberly
- Department of Geography and Environmental Sustainability, University of Oklahoma, Norman, Oklahoma, USA
| | - Leah R Johnson
- Department of Statistics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
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5
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Westphal GH, Stewart Merrill TE. Partitioning variance in immune traits in a zooplankton host-Fungal parasite system. Ecol Evol 2022; 12:e9640. [PMID: 36545366 PMCID: PMC9763022 DOI: 10.1002/ece3.9640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 11/21/2022] [Accepted: 11/29/2022] [Indexed: 12/24/2022] Open
Abstract
Host immune traits arise from both genetic and environmental sources of variation. When immune traits have a strong genetic basis, the presence and severity of disease in a population may influence the distribution of those traits. Our study addressed how two immune-related traits (gut penetrability and the hemocyte response) are shaped by genetic and environmental sources of variation, and how the presence of a virulent disease altered the relative frequency of these traits in natural populations. Daphnia dentifera hosts were sampled from five Indiana lakes between June and December 2017 before and during epidemics of their fungal pathogen, Metschnikowia bicuspidata. Collected Daphnia were experimentally exposed to Metschnikowia and assayed for their gut penetrability, hemocyte response, and multi-locus genotype. Mixed-effects models were constructed to partition variance in immune traits between genetic and environmental sources. We then isolated the genetic sources to produce genotype-specific estimates of immune traits for each multi-locus genotype. Finally, we assessed the relative frequency and dynamics of genotypes during epidemics and asked whether genotypes with more robust immune responses increased in frequency during epidemics. Although genotype was an important source of variation for both gut penetrability and the hemocyte response, environmental factors (e.g., resource availability, Metschnikowia prevalence, and co-infection) still explained a large portion of observed variation, suggesting a high degree of flexibility in Daphnia immune traits. Additionally, no significant associations were detected between a genotype's immune traits and its frequency in a population. Our study highlights the power of variance partitioning in understanding the factors driving variation in Daphnia traits and motivates further research on immunological flexibility and the ecological drivers of immune variation.
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Affiliation(s)
- Grace H. Westphal
- School of Integrative BiologyUniversity of Illinois Urbana‐ChampaignChampaignIllinoisUSA,Department of Biological ScienceFlorida State UniversityTallahasseeFloridaUSA
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6
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Lahondère C, Bonizzoni M. Thermal biology of invasive Aedes mosquitoes in the context of climate change. CURRENT OPINION IN INSECT SCIENCE 2022; 51:100920. [PMID: 35421621 DOI: 10.1016/j.cois.2022.100920] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/24/2022] [Accepted: 03/30/2022] [Indexed: 05/06/2023]
Abstract
The increasing incidence of arboviral diseases in tropical endemic areas and their emergence in new temperate countries is one of the most important challenges that Public Health agencies are currently facing. Because mosquitoes are poikilotherms, shifts in temperature influence physiological functions besides egg viability. These traits impact not only vector density, but also their interaction with their hosts and arboviruses. As such the relationship among mosquitoes, arboviral diseases and temperature is complex. Here, we summarize current knowledge on the thermal biology of Aedes invasive mosquitoes, highlighting differences among species. We also emphasize the need to expand knowledge on the variability in thermal sensitivity across populations within a species, especially in light of climate change that encompasses increase not only in mean environmental temperature but also in the frequency of hot and cold snaps. Finally, we suggest a novel experimental approach to investigate the molecular architecture of thermal adaptation in mosquitoes.
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Affiliation(s)
- Chloé Lahondère
- Department of Biochemistry, USA; The Fralin Life Science Institute, USA; Center of Emerging, Zoonotic and Arthropod-borne Pathogens, USA; The Global Change Center, USA; Department of Entomology at Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
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7
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Santos-Vega M, Martinez PP, Vaishnav KG, Kohli V, Desai V, Bouma MJ, Pascual M. The neglected role of relative humidity in the interannual variability of urban malaria in Indian cities. Nat Commun 2022; 13:533. [PMID: 35087036 PMCID: PMC8795427 DOI: 10.1038/s41467-022-28145-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 01/03/2022] [Indexed: 11/09/2022] Open
Abstract
The rapid pace of urbanization makes it imperative that we better understand the influence of climate forcing on urban malaria transmission. Despite extensive study of temperature effects in vector-borne infections in general, consideration of relative humidity remains limited. With process-based dynamical models informed by almost two decades of monthly surveillance data, we address the role of relative humidity in the interannual variability of epidemic malaria in two semi-arid cities of India. We show a strong and significant effect of humidity during the pre-transmission season on malaria burden in coastal Surat and more arid inland Ahmedabad. Simulations of the climate-driven transmission model with the MLE (Maximum Likelihood Estimates) of the parameters retrospectively capture the observed variability of disease incidence, and also prospectively predict that of 'out-of-fit' cases in more recent years, with high accuracy. Our findings indicate that relative humidity is a critical factor in the spread of urban malaria and potentially other vector-borne epidemics, and that climate change and lack of hydrological planning in cities might jeopardize malaria elimination efforts.
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Affiliation(s)
- M Santos-Vega
- Department of Ecology and Evolution, University of Chicago, Chicago, USA
- Departamento de Ingeniería Biomédica, Grupo de Investigación en Biología Matemática y Computacional BIOMAC, Universidad de los Andes, Bogotá, Colombia
| | - P P Martinez
- Department of Microbiology and Department of Statistics, University of Illinois at Urbana, Champaign, Champaign, IL, USA
| | - K G Vaishnav
- Vector Borne Diseases Control Department, Health Department, Surat Municipal Corporation, Surat, India
| | - V Kohli
- Ahmedabad Municipal Corporation, Ahmedabad, India
| | - V Desai
- Urban Health and Climate Resilience Center of Excellence, (UHCRCE), Surat, India
| | | | - M Pascual
- Department of Ecology and Evolution, University of Chicago, Chicago, USA.
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8
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Adelman ZN, Kojin BB. Malaria-Resistant Mosquitoes (Diptera: Culicidae); The Principle is Proven, But Will the Effectors Be Effective? JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:1997-2005. [PMID: 34018548 DOI: 10.1093/jme/tjab090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Indexed: 06/12/2023]
Abstract
Over the last few decades, a substantial number of anti-malarial effector genes have been evaluated for their ability to block parasite infection in the mosquito vector. While many of these approaches have yielded significant effects on either parasite intensity or prevalence of infection, just a few have been able to completely block transmission. Additionally, many approaches, while effective against the parasite, also disrupt or alter important aspects of mosquito physiology, leading to corresponding changes in lifespan, reproduction, and immunity. As the most promising approaches move towards field-based evaluation, questions of effector gene robustness and durability move to the forefront. In this forum piece, we critically evaluate past effector gene approaches with an eye towards developing a deeper pipeline to augment the current best candidates.
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Affiliation(s)
- Zach N Adelman
- Department of Entomology and AgriLife Research, Texas A&M University, College Station, TX, USA
| | - Bianca B Kojin
- Department of Entomology and AgriLife Research, Texas A&M University, College Station, TX, USA
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9
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Agyekum TP, Botwe PK, Arko-Mensah J, Issah I, Acquah AA, Hogarh JN, Dwomoh D, Robins TG, Fobil JN. A Systematic Review of the Effects of Temperature on Anopheles Mosquito Development and Survival: Implications for Malaria Control in a Future Warmer Climate. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:7255. [PMID: 34299706 PMCID: PMC8306597 DOI: 10.3390/ijerph18147255] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/17/2021] [Accepted: 06/22/2021] [Indexed: 12/17/2022]
Abstract
The rearing temperature of the immature stages can have a significant impact on the life-history traits and the ability of adult mosquitoes to transmit diseases. This review assessed published evidence of the effects of temperature on the immature stages, life-history traits, insecticide susceptibility, and expression of enzymes in the adult Anopheles mosquito. Original articles published through 31 March 2021 were systematically retrieved from Scopus, Google Scholar, Science Direct, PubMed, ProQuest, and Web of Science databases. After applying eligibility criteria, 29 studies were included. The review revealed that immature stages of An. arabiensis were more tolerant (in terms of survival) to a higher temperature than An. funestus and An. quadriannulatus. Higher temperatures resulted in smaller larval sizes and decreased hatching and pupation time. The development rate and survival of An. stephensi was significantly reduced at a higher temperature than a lower temperature. Increasing temperatures decreased the longevity, body size, length of the gonotrophic cycle, and fecundity of Anopheles mosquitoes. Higher rearing temperatures increased pyrethroid resistance in adults of the An. arabiensis SENN DDT strain, and increased pyrethroid tolerance in the An. arabiensis SENN strain. Increasing temperature also significantly increased Nitric Oxide Synthase (NOS) expression and decreased insecticide toxicity. Both extreme low and high temperatures affect Anopheles mosquito development and survival. Climate change could have diverse effects on Anopheles mosquitoes. The sensitivities of Anopeheles mosquitoes to temperature differ from species to species, even among the same complex. Notwithstanding, there seem to be limited studies on the effects of temperature on adult life-history traits of Anopheles mosquitoes, and more studies are needed to clarify this relationship.
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Affiliation(s)
- Thomas P. Agyekum
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Accra 00233, Ghana; (P.K.B.); (J.A.-M.); (I.I.); (A.A.A.); (J.N.F.)
| | - Paul K. Botwe
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Accra 00233, Ghana; (P.K.B.); (J.A.-M.); (I.I.); (A.A.A.); (J.N.F.)
| | - John Arko-Mensah
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Accra 00233, Ghana; (P.K.B.); (J.A.-M.); (I.I.); (A.A.A.); (J.N.F.)
| | - Ibrahim Issah
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Accra 00233, Ghana; (P.K.B.); (J.A.-M.); (I.I.); (A.A.A.); (J.N.F.)
| | - Augustine A. Acquah
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Accra 00233, Ghana; (P.K.B.); (J.A.-M.); (I.I.); (A.A.A.); (J.N.F.)
| | - Jonathan N. Hogarh
- Department of Environmental Science, Kwame Nkrumah University of Science and Technology, Kumasi 00233, Ghana;
| | - Duah Dwomoh
- Department of Biostatistics, School of Public Health, College of Health Sciences, University of Ghana, Accra 00233, Ghana;
| | - Thomas G. Robins
- Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA;
| | - Julius N. Fobil
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Accra 00233, Ghana; (P.K.B.); (J.A.-M.); (I.I.); (A.A.A.); (J.N.F.)
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10
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St Leger RJ. Insects and their pathogens in a changing climate. J Invertebr Pathol 2021; 184:107644. [PMID: 34237297 DOI: 10.1016/j.jip.2021.107644] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 01/02/2021] [Accepted: 06/28/2021] [Indexed: 11/19/2022]
Abstract
The complex nature of climate change-mediated multitrophic interaction is an underexplored area, but has the potential to dramatically shift transmission and distribution of many insects and their pathogens, placing some populations closer to the brink of extinction. However, for individual insect-pathogen interactions climate change will have complicated hard-to-anticipate impacts. Thus, both pathogen virulence and insect host immunity are intrinsically linked with generalized stress responses, and in both pathogen and host have extensive trade-offs with nutrition (e.g., host plant quality), growth and reproduction. Potentially alleviating or exasperating these impacts, some pathogens and hosts respond genetically and rapidly to environmental shifts. This review identifies many areas for future research including a particular need to identify how altered global warming interacts with other environmental changes and stressors, and how consistent these impacts are across pathogens and hosts. With that achieved we would be closer to producing an overarching framework to integrate knowledge on all environmental interplay and infectious disease events.
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Affiliation(s)
- Raymond J St Leger
- Department of Entomology, University of Maryland, College Park, MD 20742, USA.
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11
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Batista KKDS, Vieira CS, Florentino EB, Caruso KFB, Teixeira PTP, Moraes CDS, Genta FA, de Azambuja P, de Castro DP. Nitric oxide effects on Rhodnius prolixus's immune responses, gut microbiota and Trypanosoma cruzi development. JOURNAL OF INSECT PHYSIOLOGY 2020; 126:104100. [PMID: 32822690 DOI: 10.1016/j.jinsphys.2020.104100] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/08/2020] [Accepted: 08/14/2020] [Indexed: 05/21/2023]
Abstract
The immune system of Rhodnius prolixus comprehends the synthesis of different effectors that modulate the intestinal microbiota population and the life cycle of the parasite Trypanosoma cruzi inside the vector midgut. One of these immune responses is the production of reactive nitrogen species (RNS) derived by the action of nitric oxide synthase (NOS). Therefore, we investigated the effects of L-arginine, the substrate for nitric oxide (NO) production and Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of NOS, added in the insect blood meal. We analyzed the impact of these treatments on the immune responses and development of intestinal bacteria and parasites on R. prolixus nymphs. The L-arginine treatment in R. prolixus nymphs induced a higher NOS gene expression in the fat body and increased NO production, but reduced catalase and antimicrobial activities in the midgut. As expected, L-NAME treatment reduced NOS gene expression in the fat body. In addition, L-NAME treatment diminished catalase activity in the hemolymph and posterior midgut reduced phenoloxidase activity in the anterior midgut and increased the antimicrobial activity in the hemolymph. Both treatments caused a reduction in the cultivatable intestinal microbiota, especially in insects treated with L-NAME. However, T. cruzi development in the insect's digestive tract was suppressed after L-arginine treatment and the opposite was observed with L-NAME, which resulted in higher parasite counts. Therefore, we conclude that induction and inhibition of NOS and NO production are associated with other R. prolixus humoral immune responses, such as catalase, phenoloxidase, and antibacterial activities in different insect organs. These alterations reflect on intestinal microbiota and T. cruzi development.
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Affiliation(s)
| | - Cecília Stahl Vieira
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz (IOC/Fiocruz), Rio de Janeiro, RJ, Brazil
| | | | - Karina Francine Bravo Caruso
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz (IOC/Fiocruz), Rio de Janeiro, RJ, Brazil
| | | | - Caroline da Silva Moraes
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz (IOC/Fiocruz), Rio de Janeiro, RJ, Brazil
| | - Fernando Ariel Genta
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz (IOC/Fiocruz), Rio de Janeiro, RJ, Brazil; Departamento de Entomologia Molecular, Instituto Nacional de Entomologia Molecular (INCT-EM), Rio de Janeiro, RJ, Brazil
| | - Patrícia de Azambuja
- Departamento de Entomologia Molecular, Instituto Nacional de Entomologia Molecular (INCT-EM), Rio de Janeiro, RJ, Brazil; Programa de Pós-Graduação em Ciências e Biotecnologia, Universidade Federal Fluminense, Niteroi, RJ, Brazil
| | - Daniele Pereira de Castro
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz (IOC/Fiocruz), Rio de Janeiro, RJ, Brazil; Departamento de Entomologia Molecular, Instituto Nacional de Entomologia Molecular (INCT-EM), Rio de Janeiro, RJ, Brazil.
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Pathak AK, Shiau JC, Thomas MB, Murdock CC. Field Relevant Variation in Ambient Temperature Modifies Density-Dependent Establishment of Plasmodium falciparum Gametocytes in Mosquitoes. Front Microbiol 2019; 10:2651. [PMID: 31803169 PMCID: PMC6873802 DOI: 10.3389/fmicb.2019.02651] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 10/30/2019] [Indexed: 12/29/2022] Open
Abstract
The relationship between Plasmodium falciparum gametocyte density and infections in mosquitoes is central to understanding the rates of transmission with important implications for control. Here, we determined whether field relevant variation in environmental temperature could also modulate this relationship. Anopheles stephensi were challenged with three densities of P. falciparum gametocytes spanning a ~10-fold gradient, and housed under diurnal/daily temperature range ("DTR") of 9°C (+5°C and -4°C) around means of 20, 24, and 28°C. Vector competence was quantified as the proportion of mosquitoes infected with oocysts in the midguts (oocyst rates) or infectious with sporozoites in the salivary glands (sporozoite rates) at peak periods of infection for each temperature to account for the differences in development rates. In addition, oocyst intensities were also recorded from infected midguts and the overall study replicated across three separate parasite cultures and mosquito cohorts. While vector competence was similar at 20 DTR 9°C and 24 DTR 9°C, oocyst and sporozoite rates were also comparable, with evidence, surprisingly, for higher vector competence in mosquitoes challenged with intermediate gametocyte densities. For the same gametocyte densities however, severe reductions in the sporozoite rates was accompanied by a significant decline in overall vector competence at 28 DTR 9°C, with gametocyte density per se showing a positive and linear effect at this temperature. Unlike vector competence, oocyst intensities decreased with increasing temperatures with a predominantly positive and linear association with gametocyte density, especially at 28 DTR 9°C. Oocyst intensities across individual infected midguts suggested temperature-specific differences in mosquito susceptibility/resistance: at 20 DTR 9°C and 24 DTR 9°C, dispersion (aggregation) increased in a density-dependent manner but not at 28 DTR 9°C where the distributions were consistently random. Limitations notwithstanding, our results suggest that variation in temperature could modify seasonal dynamics of infectious reservoirs with implications for the design and deployment of transmission-blocking vaccines/drugs.
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Affiliation(s)
- Ashutosh K. Pathak
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- Center for Ecology of Infectious Diseases, University of Georgia, Athens, GA, United States
- Center for Tropical Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Justine C. Shiau
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Matthew B. Thomas
- The Department of Entomology, Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA, United States
| | - Courtney C. Murdock
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- Center for Ecology of Infectious Diseases, University of Georgia, Athens, GA, United States
- Center for Tropical Emerging Global Diseases, University of Georgia, Athens, GA, United States
- Odum School of Ecology, University of Georgia, Athens, GA, United States
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
- Riverbasin Center, University of Georgia, Athens, GA, United States
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13
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Mordecai EA, Caldwell JM, Grossman MK, Lippi CA, Johnson LR, Neira M, Rohr JR, Ryan SJ, Savage V, Shocket MS, Sippy R, Stewart Ibarra AM, Thomas MB, Villena O. Thermal biology of mosquito-borne disease. Ecol Lett 2019; 22:1690-1708. [PMID: 31286630 PMCID: PMC6744319 DOI: 10.1111/ele.13335] [Citation(s) in RCA: 262] [Impact Index Per Article: 52.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/22/2019] [Accepted: 06/06/2019] [Indexed: 12/11/2022]
Abstract
Mosquito-borne diseases cause a major burden of disease worldwide. The vital rates of these ectothermic vectors and parasites respond strongly and nonlinearly to temperature and therefore to climate change. Here, we review how trait-based approaches can synthesise and mechanistically predict the temperature dependence of transmission across vectors, pathogens, and environments. We present 11 pathogens transmitted by 15 different mosquito species - including globally important diseases like malaria, dengue, and Zika - synthesised from previously published studies. Transmission varied strongly and unimodally with temperature, peaking at 23-29ºC and declining to zero below 9-23ºC and above 32-38ºC. Different traits restricted transmission at low versus high temperatures, and temperature effects on transmission varied by both mosquito and parasite species. Temperate pathogens exhibit broader thermal ranges and cooler thermal minima and optima than tropical pathogens. Among tropical pathogens, malaria and Ross River virus had lower thermal optima (25-26ºC) while dengue and Zika viruses had the highest (29ºC) thermal optima. We expect warming to increase transmission below thermal optima but decrease transmission above optima. Key directions for future work include linking mechanistic models to field transmission, combining temperature effects with control measures, incorporating trait variation and temperature variation, and investigating climate adaptation and migration.
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Affiliation(s)
- Erin A. Mordecai
- Department of BiologyStanford University371 Serra MallStanfordCAUSA
| | | | - Marissa K. Grossman
- Department of Entomology and Center for Infectious Disease DynamicsPenn State UniversityUniversity ParkPA16802USA
| | - Catherine A. Lippi
- Department of Geography and Emerging Pathogens InstituteUniversity of FloridaGainesvilleFLUSA
| | - Leah R. Johnson
- Department of StatisticsVirginia Polytechnic and State University250 Drillfield DriveBlacksburgVAUSA
| | - Marco Neira
- Center for Research on Health in Latin America (CISeAL)Pontificia Universidad Católica del EcuadorQuitoEcuador
| | - Jason R. Rohr
- Department of Biological SciencesEck Institute of Global HealthEnvironmental Change InitiativeUniversity of Notre Dame, Notre DameINUSA
| | - Sadie J. Ryan
- Department of Geography and Emerging Pathogens InstituteUniversity of FloridaGainesvilleFLUSA
- School of Life SciencesUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Van Savage
- Department of Ecology and Evolutionary Biology and Department of BiomathematicsUniversity of California Los AngelesLos AngelesCA90095USA
- Santa Fe Institute1399 Hyde Park RdSanta FeNM87501USA
| | - Marta S. Shocket
- Department of BiologyStanford University371 Serra MallStanfordCAUSA
| | - Rachel Sippy
- Department of Geography and Emerging Pathogens InstituteUniversity of FloridaGainesvilleFLUSA
- Institute for Global Health and Translational SciencesSUNY Upstate Medical UniversitySyracuseNY13210USA
| | - Anna M. Stewart Ibarra
- Institute for Global Health and Translational SciencesSUNY Upstate Medical UniversitySyracuseNY13210USA
| | - Matthew B. Thomas
- Department of Entomology and Center for Infectious Disease DynamicsPenn State UniversityUniversity ParkPA16802USA
| | - Oswaldo Villena
- Department of StatisticsVirginia Polytechnic and State University250 Drillfield DriveBlacksburgVAUSA
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14
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Ramírez AL, van den Hurk AF, Mackay IM, Yang ASP, Hewitson GR, McMahon JL, Boddey JA, Ritchie SA, Erickson SM. Malaria surveillance from both ends: concurrent detection of Plasmodium falciparum in saliva and excreta harvested from Anopheles mosquitoes. Parasit Vectors 2019; 12:355. [PMID: 31319880 PMCID: PMC6639908 DOI: 10.1186/s13071-019-3610-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 07/08/2019] [Indexed: 12/03/2022] Open
Abstract
Background Malaria is the most important vector-borne disease in the world. Epidemiological and ecological studies of malaria traditionally utilize detection of Plasmodium sporozoites in whole mosquitoes or salivary glands by microscopy or serological or molecular assays. However, these methods are labor-intensive, and can over- or underestimate mosquito transmission potential. To overcome these limitations, alternative sample types have been evaluated for the study of malaria. It was recently shown that Plasmodium could be detected in saliva expectorated on honey-soaked cards by Anopheles stephensi, providing a better estimate of transmission risk. We evaluated whether excretion of Plasmodium falciparum nucleic acid by An. stephensi correlates with expectoration of parasites in saliva, thus providing an additional sample type for estimating transmission potential. Mosquitoes were exposed to infectious blood meals containing cultured gametocytes, and excreta collected at different time points post-exposure. Saliva was collected on honey-soaked filter paper cards, and salivary glands were dissected and examined microscopically for sporozoites. Excreta and saliva samples were tested by real time polymerase chain reaction (RT-rtPCR). Results Plasmodium falciparum RNA was detected in mosquito excreta as early as four days after ingesting a bloodmeal containing gametocytes. Once sporogony (the development of sporozoites) occurred, P. falciparum RNA was detected concurrently in both excreta and saliva samples. In the majority of cases, no difference was observed between the Ct values obtained from matched excreta and saliva samples, suggesting that both samples provide equally sensitive results. A positive association was observed between the molecular detection of the parasites in both samples and the proportion of mosquitoes with sporozoites in their salivary glands from each container. No distinguishable parasites were observed when excreta samples were stained and microscopically analyzed. Conclusions Mosquito saliva and excreta are easily collected and are promising for surveillance of malaria-causing parasites, especially in low transmission settings or in places where arboviruses co-circulate. Electronic supplementary material The online version of this article (10.1186/s13071-019-3610-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ana L Ramírez
- College of Public Health, Medical and Veterinary Sciences, James Cook University, PO Box 6811, Cairns, QLD, 4870, Australia. .,Australian Institute of Tropical Health and Medicine, James Cook University, PO Box 6811, Cairns, QLD, 4870, Australia.
| | - Andrew F van den Hurk
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Coopers Plains, QLD, 4108, Australia
| | - Ian M Mackay
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Coopers Plains, QLD, 4108, Australia
| | - Annie S P Yang
- Infection and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3052, Australia.,Department of Medical Microbiology Parasitology, Radboud University Medical Center, Geert Grooteplein 28, Microbiology 268, 6500 HB, Nijmegen, The Netherlands
| | - Glen R Hewitson
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Coopers Plains, QLD, 4108, Australia
| | - Jamie L McMahon
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Coopers Plains, QLD, 4108, Australia
| | - Justin A Boddey
- Infection and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Scott A Ritchie
- College of Public Health, Medical and Veterinary Sciences, James Cook University, PO Box 6811, Cairns, QLD, 4870, Australia.,Australian Institute of Tropical Health and Medicine, James Cook University, PO Box 6811, Cairns, QLD, 4870, Australia
| | - Sara M Erickson
- Infection and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3052, Australia
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15
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Chu VM, Sallum MAM, Moore TE, Lainhart W, Schlichting CD, Conn JE. Regional variation in life history traits and plastic responses to temperature of the major malaria vector Nyssorhynchus darlingi in Brazil. Sci Rep 2019; 9:5356. [PMID: 30926833 PMCID: PMC6441093 DOI: 10.1038/s41598-019-41651-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Accepted: 03/13/2019] [Indexed: 11/08/2022] Open
Abstract
The primary Brazilian malaria vector, Nyssorhynchus darlingi (formerly Anopheles darlingi), ranges from 0°S-23°S across three biomes (Amazonia, Cerrado, Mata Atlântica). Rising temperatures will increase mosquito developmental rates, and models predict future malaria transmission by Ny. darlingi in Brazil will shift southward. We reared F1 Ny. darlingi (progeny of field-collected females from 4 state populations across Brazil) at three temperatures (20, 24, 28 °C) and measured key life-history traits. Our results reveal geographic variation due to both genetic differences among localities and plastic responses to temperature differences. Temperature significantly altered all traits: faster larval development, shorter adult life and overall lifespan, and smaller body sizes were seen at 28 °C versus 20 °C. Low-latitude Amazonia mosquitoes had the fastest larval development at all temperatures, but at 28 °C, average development rate of high-latitude Mata Atlântica mosquitoes was accelerated and equivalent to low-latitude Amazonia. Body size of adult mosquitoes from the Mata Atlântica remained larger at all temperatures. We detected genetic variation in the plastic responses among mosquitoes from different localities, with implications for malaria transmission under climate change. Faster development combined with larger body size, without a tradeoff in adult longevity, suggests vectorial capacities of some Mata Atlântica populations may significantly increase under warming climates.
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Affiliation(s)
- V M Chu
- Department of Biomedical Sciences, School of Public Health, University at Albany (State University of New York), Albany, NY, USA.
- Wadsworth Center, New York State Department of Health, Albany, NY, USA.
| | - M A M Sallum
- Departamento de Epidemiologia, Faculdade de Saúde Pública, Universidade de São Paulo, São Paulo, SP, Brazil
| | - T E Moore
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - W Lainhart
- Department of Biomedical Sciences, School of Public Health, University at Albany (State University of New York), Albany, NY, USA
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
- Department of Pathology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - C D Schlichting
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - J E Conn
- Department of Biomedical Sciences, School of Public Health, University at Albany (State University of New York), Albany, NY, USA.
- Wadsworth Center, New York State Department of Health, Albany, NY, USA.
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16
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Souvannaseng L, Hun LV, Baker H, Klyver JM, Wang B, Pakpour N, Bridgewater JM, Napoli E, Giulivi C, Riehle MA, Luckhart S. Inhibition of JNK signaling in the Asian malaria vector Anopheles stephensi extends mosquito longevity and improves resistance to Plasmodium falciparum infection. PLoS Pathog 2018; 14:e1007418. [PMID: 30496310 PMCID: PMC6264519 DOI: 10.1371/journal.ppat.1007418] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 10/18/2018] [Indexed: 11/18/2022] Open
Abstract
Malaria is a global health concern caused by infection with Plasmodium parasites. With rising insecticide and drug resistance, there is a critical need to develop novel control strategies, including strategies to block parasite sporogony in key mosquito vector species. MAPK signaling pathways regulated by extracellular signal-regulated kinases (ERKs) and the stress-activated protein kinases (SAPKs) c-Jun N-terminal kinases (JNKs) and p38 MAPKs are highly conserved across eukaryotes, including mosquito vectors of the human malaria parasite Plasmodium falciparum. Some of these pathways in mosquitoes have been investigated in detail, but the mechanisms of integration of parasite development and mosquito fitness by JNK signaling have not been elucidated. To this end, we engineered midgut-specific overexpression of MAPK phosphatase 4 (MKP4), which targets the SAPKs, and used two potent and specific JNK small molecule inhibitors (SMIs) to assess the effects of JNK signaling manipulations on Anopheles stephensi fecundity, lifespan, intermediary metabolism, and P. falciparum development. MKP4 overexpression and SMI treatment reduced the proportion of P. falciparum-infected mosquitoes and decreased oocyst loads relative to controls. SMI-treated mosquitoes exhibited no difference in lifespan compared to controls, whereas genetically manipulated mosquitoes exhibited extended longevity. Metabolomics analyses of SMI-treated mosquitoes revealed insights into putative resistance mechanisms and the physiology behind lifespan extension, suggesting for the first time that P. falciparum-induced JNK signaling reduces mosquito longevity and increases susceptibility to infection, in contrast to previously published reports, likely via a critical interplay between the invertebrate host and parasite for nutrients that play essential roles during sporogonic development. Malaria is a global health concern caused by infection with Plasmodium parasites. With rising insecticide and drug resistance, there is a critical need to develop novel control strategies. One strategy is to develop a Plasmodium-resistant mosquito through the manipulation of key signaling pathways and processes in the mosquito midgut, a critical tissue for parasite development. MAPK signaling pathways are highly conserved among eukaryotes and regulate development of the human malaria parasite Plasmodium falciparum in the mosquito vector. Here, we investigated how manipulation of Anopheles stephensi JNK signaling affects development of P. falciparum and key mosquito life history traits. We used multiple, complementary approaches to demonstrate that malaria parasite infection activates mosquito JNK signaling for its own benefit at a cost to host lifespan. Notably, these combined effects derive from networked signaling with other transduction pathways and alterations to intermediary metabolism in the mosquito host.
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Affiliation(s)
- Lattha Souvannaseng
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, CA, United States of America
- Department of Pathobiology, St. George's University, School of Veterinary Medicine, True Blue, St. George, Grenada, West Indies
| | - Lewis Vibul Hun
- Department of Entomology, University of Arizona, Tucson, AZ, United States of America
| | - Heather Baker
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, CA, United States of America
| | - John M. Klyver
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, CA, United States of America
| | - Bo Wang
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, CA, United States of America
| | - Nazzy Pakpour
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, CA, United States of America
| | - Jordan M. Bridgewater
- Department of Entomology, University of Arizona, Tucson, AZ, United States of America
| | - Eleonora Napoli
- Department of Molecular Biosciences, University of California, Davis, Davis, CA
| | - Cecilia Giulivi
- Department of Molecular Biosciences, University of California, Davis, Davis, CA
- M.I.N.D. Institute, Sacramento, CA, United States of America
| | - Michael A. Riehle
- Department of Entomology, University of Arizona, Tucson, AZ, United States of America
| | - Shirley Luckhart
- Department of Entomology, Plant Pathology and Nematology and Department of Biological Sciences, University of Idaho, Moscow, ID, United States of America
- * E-mail:
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17
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Benelli G. Managing mosquitoes and ticks in a rapidly changing world - Facts and trends. Saudi J Biol Sci 2018; 26:921-929. [PMID: 31303820 PMCID: PMC6600734 DOI: 10.1016/j.sjbs.2018.06.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/06/2018] [Accepted: 06/26/2018] [Indexed: 02/08/2023] Open
Abstract
Vector-borne diseases transmitted by mosquitoes and ticks are on the rise. The effective and sustainable control of these arthropod vectors is a puzzling challenge for public health worldwide. In the present review, I attempted to provide a concise and updated overview of the current mosquito and tick research scenario. The wide array of control tools recently developed has been considered, with special reference to those approved by the World Health Organization Vector Control Advisory Group (WHO VCAG), as well as novel ones with an extremely promising potential to be exploited in vector control programs. Concerning mosquitoes, a major focus has been given on genetically modified vectors, eave tubes, attractive toxic sugar baits (ATSB) and biocontrol agents. Regarding ticks, the recent development of highly effective repellents and acaricides (including nanoformulated ones) as well as behavior-based control tools, has been highlighted. In the second part of the review, key research questions about biology and control of mosquitoes and ticks have been critically formulated. A timely research agenda outlining hot issues to be addressed in mosquito and tick research is provided. Overall, it is expected that the present review will contribute to boost research and applications on successful mosquito and tick control strategies, along with an improved knowledge of their biology and ecology.
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Affiliation(s)
- Giovanni Benelli
- Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy.,The BioRobotics Institute, Sant'Anna School of Advanced Studies, viale Rinaldo Piaggio 34, 56025, Pontedera, Pisa, Italy
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18
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Lefevre T, Ohm J, Dabiré KR, Cohuet A, Choisy M, Thomas MB, Cator L. Transmission traits of malaria parasites within the mosquito: Genetic variation, phenotypic plasticity, and consequences for control. Evol Appl 2017; 11:456-469. [PMID: 29636799 PMCID: PMC5891056 DOI: 10.1111/eva.12571] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 10/23/2017] [Indexed: 12/16/2022] Open
Abstract
Evaluating the risk of emergence and transmission of vector‐borne diseases requires knowledge of the genetic and environmental contributions to pathogen transmission traits. Compared to the significant effort devoted to understanding the biology of malaria transmission from vertebrate hosts to mosquito vectors, the strategies that malaria parasites have evolved to maximize transmission from vectors to vertebrate hosts have been largely overlooked. While determinants of infection success within the mosquito host have recently received attention, the causes of variability for other key transmission traits of malaria, namely the duration of parasite development and its virulence within the vector, as well as its ability to alter mosquito behavior, remain largely unknown. This important gap in our knowledge needs to be bridged in order to obtain an integrative view of the ecology and evolution of malaria transmission strategies. Associations between transmission traits also need to be characterized, as they trade‐offs and constraints could have important implications for understanding the evolution of parasite transmission. Finally, theoretical studies are required to evaluate how genetic and environmental influences on parasite transmission traits can shape malaria dynamics and evolution in response to disease control.
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Affiliation(s)
- Thierry Lefevre
- MIVEGEC, IRD, CNRS University of Montpellier Montpellier France.,Institut de Recherche en Sciences de la Santé (IRSS) Bobo Dioulasso Burkina Faso.,Laboratoire Mixte International sur les Vecteurs (LAMIVECT) Bobo Dioulasso Burkina Faso
| | - Johanna Ohm
- Department of Entomology and Center for Infectious Disease Dynamics Penn State University University Park PA USA
| | - Kounbobr R Dabiré
- Institut de Recherche en Sciences de la Santé (IRSS) Bobo Dioulasso Burkina Faso.,Laboratoire Mixte International sur les Vecteurs (LAMIVECT) Bobo Dioulasso Burkina Faso
| | - Anna Cohuet
- MIVEGEC, IRD, CNRS University of Montpellier Montpellier France
| | - Marc Choisy
- MIVEGEC, IRD, CNRS University of Montpellier Montpellier France.,Oxford University Clinical Research Unit Hanoi Vietnam
| | - Matthew B Thomas
- Department of Entomology and Center for Infectious Disease Dynamics Penn State University University Park PA USA
| | - Lauren Cator
- Grand Challenges in Ecosystems and Environment Imperial College London Ascot UK
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19
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Laughton AM, O'Connor CO, Knell RJ. Responses to a warming world: Integrating life history, immune investment, and pathogen resistance in a model insect species. Ecol Evol 2017; 7:9699-9710. [PMID: 29188001 PMCID: PMC5696387 DOI: 10.1002/ece3.3506] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 09/06/2017] [Accepted: 09/13/2017] [Indexed: 01/31/2023] Open
Abstract
Environmental temperature has important effects on the physiology and life history of ectothermic animals, including investment in the immune system and the infectious capacity of pathogens. Numerous studies have examined individual components of these complex systems, but little is known about how they integrate when animals are exposed to different temperatures. Here, we use the Indian meal moth (Plodia interpunctella) to understand how immune investment and disease resistance react and potentially trade‐off with other life‐history traits. We recorded life‐history (development time, survival, fecundity, and body size) and immunity (hemocyte counts, phenoloxidase activity) measures and tested resistance to bacterial (E. coli) and viral (Plodia interpunctella granulosis virus) infection at five temperatures (20–30°C). While development time, lifespan, and size decreased with temperature as expected, moths exhibited different reproductive strategies in response to small changes in temperature. At cooler temperatures, oviposition rates were low but tended to increase toward the end of life, whereas warmer temperatures promoted initially high oviposition rates that rapidly declined after the first few days of adult life. Although warmer temperatures were associated with strong investment in early reproduction, there was no evidence of an associated trade‐off with immune investment. Phenoloxidase activity increased most at cooler temperatures before plateauing, while hemocyte counts increased linearly with temperature. Resistance to bacterial challenge displayed a complex pattern, whereas survival after a viral challenge increased with rearing temperature. These results demonstrate that different immune system components and different pathogens can respond in distinct ways to changes in temperature. Overall, these data highlight the scope for significant changes in immunity, disease resistance, and host–parasite population dynamics to arise from small, biologically relevant changes to environmental temperature. In light of global warming, understanding these complex interactions is vital for predicting the potential impact of insect disease vectors and crop pests on public health and food security.
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Affiliation(s)
- Alice M Laughton
- School of Biological and Chemical Sciences Queen Mary University of London London UK
| | - Cian O O'Connor
- School of Biological and Chemical Sciences Queen Mary University of London London UK
| | - Robert J Knell
- School of Biological and Chemical Sciences Queen Mary University of London London UK
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20
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Liew JW, Fong MY, Lau YL. Quantitative real-time PCR analysis of Anopheles dirus TEP1 and NOS during Plasmodium berghei infection, using three reference genes. PeerJ 2017; 5:e3577. [PMID: 28761783 PMCID: PMC5533154 DOI: 10.7717/peerj.3577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 06/23/2017] [Indexed: 01/12/2023] Open
Abstract
Quantitative reverse transcription PCR (qRT-PCR) has been an integral part of characterizing the immunity of Anopheles mosquitoes towards Plasmodium invasion. Two anti-Plasmodium factors of Anopheles, thioester-containing protein 1 (TEP1) and nitric oxide synthase (NOS), play a role in the refractoriness of Anopheles towards Plasmodium infection and are generally expressed during infection. However, these are less studied in Anopheles dirus, a dominant malaria vector in Southeast Asia. Furthermore, most studies used a single reference gene for normalization during gene expression analysis without proper validation. This may lead to erroneous quantification of expression levels. Therefore, the present study characterized and investigated the expression profiles of TEP1 and NOS of Anopheles dirus during P. berghei infection. Prior to that, the elongation factor 1-alpha (EF1), actin 1 (Act) and ribosomal protein S7 (S7) genes were validated for their suitability as a set of reference genes. TEP1 and NOS expressions in An. dirus were found to be significantly induced after P. berghei infection.
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Affiliation(s)
- Jonathan W.K. Liew
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mun Yik Fong
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yee Ling Lau
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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21
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Fine-scale variation in microclimate across an urban landscape shapes variation in mosquito population dynamics and the potential of Aedes albopictus to transmit arboviral disease. PLoS Negl Trop Dis 2017; 11:e0005640. [PMID: 28558030 PMCID: PMC5466343 DOI: 10.1371/journal.pntd.0005640] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 06/09/2017] [Accepted: 05/12/2017] [Indexed: 11/19/2022] Open
Abstract
Most statistical and mechanistic models used to predict mosquito-borne disease transmission incorporate climate drivers of disease transmission by utilizing environmental data collected at geographic scales that are potentially coarser than what mosquito populations may actually experience. Temperature and relative humidity can vary greatly between indoor and outdoor environments, and can be influenced strongly by variation in landscape features. In the Aedes albopictus system, we conducted a proof-of-concept study in the vicinity of the University of Georgia to explore the effects of fine-scale microclimate variation on mosquito life history and vectorial capacity (VC). We placed Ae. albopictus larvae in artificial pots distributed across three replicate sites within three different land uses–urban, suburban, and rural, which were characterized by high, intermediate, and low proportions of impervious surfaces. Data loggers were placed into each larval environment and in nearby vegetation to record daily variation in water and ambient temperature and relative humidity. The number of adults emerging from each pot and their body size and sex were recorded daily. We found mosquito microclimate to significantly vary across the season as well as with land use. Urban sites were in general warmer and less humid than suburban and rural sites, translating into decreased larval survival, smaller body sizes, and lower per capita growth rates of mosquitoes on urban sites. Dengue transmission potential was predicted to be higher in the summer than the fall. Additionally, the effects of land use on dengue transmission potential varied by season. Warm summers resulted in a higher predicted VC on the cooler, rural sites, while warmer, urban sites had a higher predicted VC during the cooler fall season. Environmental factors influence the dynamics of mosquito-borne disease transmission. Most models used to predict mosquito-borne disease transmission incorporate climate data collected at coarser scales than mosquitoes typically experience. Climate conditions can vary greatly between indoor and outdoor environments, and are influenced by landscape features. We conducted a field experiment with the Asian tiger mosquito to explore how microclimate variation across an urban landscape affects mosquito life history and potential to transmit arboviruses, like dengue. We demonstrate that climate conditions captured by weather stations do not reflect relevant mosquito microclimate, and that subtle variation in mean and diurnal ranges of temperature and relative humidity can lead to appreciable variation in key mosquito / pathogen traits that are important for transmission. Our results have implications for statistical and mechanistic models used to predict variation in transmission across seasons, regions, and land uses, but also for building in realistic environmental variation in laboratory work on mosquito-pathogen interactions. Finally, the variation in microclimate we observed across land use was subtle; likely because our study site is a relatively small city. Nevertheless, these translated into considerable differences in mosquito traits and dengue transmission potential, suggesting these effects could be much larger in more expansive cities.
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Shragai T, Tesla B, Murdock C, Harrington LC. Zika and chikungunya: mosquito-borne viruses in a changing world. Ann N Y Acad Sci 2017; 1399:61-77. [PMID: 28187236 DOI: 10.1111/nyas.13306] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Revised: 11/21/2016] [Accepted: 12/02/2016] [Indexed: 12/16/2022]
Abstract
The reemergence and growing burden of mosquito-borne virus infections have incited public fear and growing research efforts to understand the mechanisms of infection-associated health outcomes and to provide better approaches for mosquito vector control. While efforts to develop therapeutics, vaccines, and novel genetic mosquito-control technologies are underway, many important underlying ecological questions remain that could significantly enhance our understanding and ability to predict and prevent transmission. Here, we review the current knowledge about the transmission ecology of two recent arbovirus invaders, the chikungunya and Zika viruses. We introduce the viruses and mosquito vectors, highlighting viral biology, historical routes of transmission, and viral mechanisms facilitating rapid global invasion. In addition, we review factors contributing to vector global invasiveness and transmission efficiency. We conclude with a discussion of how human-induced biotic and abiotic environmental changes facilitate mosquito-borne virus transmission, emphasizing critical gaps in understanding. These knowledge gaps are tremendous; much of our data on basic mosquito ecology in the field predate 1960, and the mosquitoes themselves, as well as the world they live in, have substantially changed. A concerted investment in understanding the basic ecology of these vectors, which serve as the main drivers of pathogen transmission in both wildlife and human populations, is now more important than ever.
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Affiliation(s)
- Talya Shragai
- Department of Entomology, Cornell University, Ithaca, New York
| | - Blanka Tesla
- Department of Infectious Diseases and Odum School of Ecology, University of Georgia, Athens, Georgia
| | - Courtney Murdock
- Department of Infectious Diseases and Odum School of Ecology, University of Georgia, Athens, Georgia
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Santos-Vega M, Martinez PP, Pascual M. Climate forcing and infectious disease transmission in urban landscapes: integrating demographic and socioeconomic heterogeneity. Ann N Y Acad Sci 2016; 1382:44-55. [PMID: 27681053 DOI: 10.1111/nyas.13229] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/15/2016] [Accepted: 08/18/2016] [Indexed: 01/23/2023]
Abstract
Urbanization and climate change are the two major environmental challenges of the 21st century. The dramatic expansion of cities around the world creates new conditions for the spread, surveillance, and control of infectious diseases. In particular, urban growth generates pronounced spatial heterogeneity within cities, which can modulate the effect of climate factors at local spatial scales in large urban environments. Importantly, the interaction between environmental forcing and socioeconomic heterogeneity at local scales remains an open area in infectious disease dynamics, especially for urban landscapes of the developing world. A quantitative and conceptual framework on urban health with a focus on infectious diseases would benefit from integrating aspects of climate forcing, population density, and level of wealth. In this paper, we review what is known about these drivers acting independently and jointly on urban infectious diseases; we then outline elements that are missing and would contribute to building such a framework.
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Affiliation(s)
| | - Pamela P Martinez
- Ecology and Evolution Department, University of Chicago, Chicago, Illinois
| | - Mercedes Pascual
- Ecology and Evolution Department, University of Chicago, Chicago, Illinois
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24
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Barreaux AM, Barreaux P, Thievent K, Koella JC. Larval environment influences vector competence of the malaria mosquito Anopheles gambiae. MALARIAWORLD JOURNAL 2016; 7:8. [PMID: 38601358 PMCID: PMC11003208 DOI: 10.5281/zenodo.10798340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Background While environmental factors such as temperature can influence the vector competence of mosquitoes directly, for example by affecting the longevity of the mosquito and the development of the malaria parasite they may also have an indirect impact on the parasite's transmission. By influencing larval development, they may affect the adult traits that are important for the parasite's development and transmission. We studied the influence of two larval environmental factors, food availability and temperature, on the probability that mosquitoes infected with the malaria parasite survived to harbour sporozoites in their salivary glands. Materials and methods Anopheles gambiae larvae were reared at 21ºC, 25ºC or 29ºC, and fed either a standard larval diet or half of it. Adults could blood feed on mice harbouring the infectious gametocytic stage of Plasmodium berghei ANKA transformed with green fluorescent protein (GFP). Survival was assessed every 24 hrs up to 21 days post infection, when surviving mosquitoes were dissected to check the salivary glands for sporozoites with a fluorescent microscope sensitive to GFP. Using a binomial GLM we analysed 'vector competence', i.e. if mosquitoes survived until dissection and harboured sporozoites in their salivary glands. Results Vector competence dropped by about a third if we fed larvae half the standard food regime. The effect of temperature during the larval period depended strongly on the food regime. At low food, increasing temperature from 21ºC to 29ºC increased vector competence from about 0.18 to 0.48, whereas at standard food, vector competence dropped from about 0.67 at 21ºC to 0.56 at 29ºC. Conclusions Thus, perceptions and models about the role of environmental change on the transmission of malaria should include how the environment changes adult life-history by influencing larval development.
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Affiliation(s)
- Antoine M.G. Barreaux
- Laboratory of Ecology and Epidemiology of Parasites, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
- Merkle Lab, Department of Entomology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Priscille Barreaux
- Laboratory of Ecology and Epidemiology of Parasites, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
- Merkle Lab, Department of Entomology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Kevin Thievent
- Laboratory of Ecology and Epidemiology of Parasites, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
| | - Jacob C. Koella
- Laboratory of Ecology and Epidemiology of Parasites, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
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Palinauskas V, Žiegytė R, Iezhova TA, Ilgūnas M, Bernotienė R, Valkiūnas G. Description, molecular characterisation, diagnostics and life cycle of Plasmodium elongatum (lineage pERIRUB01), the virulent avian malaria parasite. Int J Parasitol 2016; 46:697-707. [PMID: 27349510 DOI: 10.1016/j.ijpara.2016.05.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 05/09/2016] [Accepted: 05/17/2016] [Indexed: 12/11/2022]
Abstract
Plasmodium elongatum causes severe avian malaria and is distributed worldwide. This parasite is of particular importance due to its ability to develop and cause lethal malaria not only in natural hosts, but also in non-adapted endemic birds such as the brown kiwi and different species of penguins. Information on vectors of this infection is available but is contradictory. PCR-based analysis indicated the possible existence of a cluster of closely related P. elongatum lineages which might differ in their ability to develop in certain mosquitoes and birds. This experimental study provides information about molecular and morphological characterisation of a virulent P. elongatum strain (lineage pERIRUB01) isolated from a naturally infected European robin, Erithacus rubecula. Phylogenetic analysis based on partial cytochrome b gene sequences showed that this parasite lineage is closely related to P. elongatum (lineage pGRW6). Blood stages of both parasite lineages are indistinguishable, indicating that they belong to the same species. Both pathogens develop in experimentally infected canaries, Serinus canaria, causing death of the hosts. In both these lineages, trophozoites and erythrocytic meronts develop in polychromatic erythrocytes and erythroblasts, gametocytes parasitize mature erythrocytes, exoerythrocytic stages develop in cells of the erythrocytic series in bone marrow and are occasionally reported in spleen and liver. Massive infestation of bone marrow cells is the main reason for bird mortality. We report here on syncytium-like remnants of tissue meronts, which slip out of the bone marrow into the peripheral circulation, providing evidence that the syncytia can be a template for PCR amplification. This finding contributes to better understanding positive PCR amplifications in birds when parasitemia is invisible and improved diagnostics of abortive haemosporidian infections. Sporogony of P. elongatum (pERIRUB01) completes the cycle and sporozoites develop in widespread Culex quinquefasciatus and Culex pipiens pipiens form molestus mosquitoes. This experimental study provides information on virulence and within species lineage diversity in a single pathogenic species of haemosporidian parasite.
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Affiliation(s)
| | - Rita Žiegytė
- Nature Research Centre, Akademijos 2, LT-08412 Vilnius, Lithuania
| | | | - Mikas Ilgūnas
- Nature Research Centre, Akademijos 2, LT-08412 Vilnius, Lithuania
| | - Rasa Bernotienė
- Nature Research Centre, Akademijos 2, LT-08412 Vilnius, Lithuania
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Parham PE, Waldock J, Christophides GK, Hemming D, Agusto F, Evans KJ, Fefferman N, Gaff H, Gumel A, LaDeau S, Lenhart S, Mickens RE, Naumova EN, Ostfeld RS, Ready PD, Thomas MB, Velasco-Hernandez J, Michael E. Climate, environmental and socio-economic change: weighing up the balance in vector-borne disease transmission. Philos Trans R Soc Lond B Biol Sci 2015; 370:rstb.2013.0551. [PMID: 25688012 DOI: 10.1098/rstb.2013.0551] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Arguably one of the most important effects of climate change is the potential impact on human health. While this is likely to take many forms, the implications for future transmission of vector-borne diseases (VBDs), given their ongoing contribution to global disease burden, are both extremely important and highly uncertain. In part, this is owing not only to data limitations and methodological challenges when integrating climate-driven VBD models and climate change projections, but also, perhaps most crucially, to the multitude of epidemiological, ecological and socio-economic factors that drive VBD transmission, and this complexity has generated considerable debate over the past 10-15 years. In this review, we seek to elucidate current knowledge around this topic, identify key themes and uncertainties, evaluate ongoing challenges and open research questions and, crucially, offer some solutions for the field. Although many of these challenges are ubiquitous across multiple VBDs, more specific issues also arise in different vector-pathogen systems.
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Affiliation(s)
- Paul E Parham
- Department of Public Health and Policy, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 3GL, UK Grantham Institute for Climate Change, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Joanna Waldock
- The Cyprus Institute, Nicosia, Cyprus Imperial College London, London SW7 2AZ, UK
| | | | - Deborah Hemming
- Meteorological Office Hadley Centre, UK Meteorological Office, Fitzroy Road, Exeter, EX1 3PB, UK
| | - Folashade Agusto
- Department of Mathematics, Austin Peay State University, Clarksville, TN 37044, USA
| | - Katherine J Evans
- Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA
| | - Nina Fefferman
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ 08901, USA
| | - Holly Gaff
- Department of Biological Sciences, Old Dominium University, Norfolk, VA 23529, USA
| | - Abba Gumel
- Simon A. Levin Mathematical, Computational and Modeling Sciences Center, Arizona State University, Tempe, AZ 85287-1904, USA School of Mathematical and Natural Sciences, Arizona State University, Phoenix, AZ 85069-7100, USA
| | - Shannon LaDeau
- Cary Institute of Ecosystem Studies, PO Box AB, Millbrook, NY 12545-0129, USA
| | - Suzanne Lenhart
- Department of Mathematics, University of Tennessee, Knoxville, TN 37996-1300, USA
| | - Ronald E Mickens
- Department of Physics, Clark Atlanta University, PO Box 172, Atlanta, GA 30314, USA
| | - Elena N Naumova
- Department of Civil and Environmental Engineering, Tufts University School of Engineering, Medford, MA 02155, USA
| | - Richard S Ostfeld
- Cary Institute of Ecosystem Studies, PO Box AB, Millbrook, NY 12545-0129, USA
| | - Paul D Ready
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Matthew B Thomas
- Department of Entomology, Pennsylvania State University, University Park, PA 16802, USA
| | - Jorge Velasco-Hernandez
- Universidad Nacional Autnoma de Mexico Institute of Mathematics Mexico City, Distrito Federal, Mexico
| | - Edwin Michael
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-0369, USA
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Shikano I, Cory JS. Impact Of Environmental Variation On Host Performance Differs With Pathogen Identity: Implications For Host-Pathogen Interactions In A Changing Climate. Sci Rep 2015; 5:15351. [PMID: 26477393 PMCID: PMC4609993 DOI: 10.1038/srep15351] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 09/23/2015] [Indexed: 01/16/2023] Open
Abstract
Specialist and generalist pathogens may exert different costs on their hosts; thereby altering the way hosts cope with environmental variation. We examined how pathogen-challenge alters the environmental conditions that maximize host performance by simultaneously varying temperature and nutrition (protein to carbohydrate ratio; P:C) after exposure to two baculoviruses; one that is specific to the cabbage looper, Trichoplusia ni (TnSNPV) and another that has a broad host range (AcMNPV). Virus-challenged larvae performed better on more protein-biased diets, primarily due to higher survival, whereas unchallenged larvae performed best on a balanced diet. The environmental conditions that maximized host performance differed with virus identity because TnSNPV-challenge inflicted fitness costs (reduced pupal weight and prolonged development) whereas AcMNPV-challenge did not. The performance of TnSNPV-challenged larvae rose with increasing P:C across all temperatures, whereas temperature modulated the optimal P:C in AcMNPV-challenged larvae (slightly protein-biased at 16 °C to increasingly higher P:C as temperature increased). Increasing temperature reduced pupal size, but only at more balanced P:C ratios, indicating that nutrition moderates the temperature-size rule. Our findings highlight the complex environmental interactions that can alter host performance after exposure to pathogens, which could impact the role of entomopathogens as regulators of insect populations in a changing climate.
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Affiliation(s)
- Ikkei Shikano
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A1S6, Canada
| | - Jenny S. Cory
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A1S6, Canada
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28
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Gervasi SS, Civitello DJ, Kilvitis HJ, Martin LB. The context of host competence: a role for plasticity in host-parasite dynamics. Trends Parasitol 2015; 31:419-25. [PMID: 26048486 PMCID: PMC4567474 DOI: 10.1016/j.pt.2015.05.002] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 04/15/2015] [Accepted: 05/05/2015] [Indexed: 12/17/2022]
Abstract
Even apparently similar hosts can respond differently to the same parasites. Some individuals or specific groups of individuals disproportionately affect disease dynamics. Understanding the sources of among-host heterogeneity in the ability to transmit parasites would improve disease management. A major source of host variation might be phenotypic plasticity - the tendency for phenotypes to change across different environments. Plasticity might be as important as, or even more important than, genetic change, especially in light of human modifications of the environment, because it can occur on a more rapid timescale than evolution. We argue that variation in phenotypic plasticity among and within species strongly contributes to epidemiological dynamics when parasites are shared among multiple hosts, which is often the case.
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Affiliation(s)
- Stephanie S Gervasi
- Department of Integrative Biology, University of South Florida, Science Center 110, Tampa, FL 33620, USA.
| | - David J Civitello
- Department of Integrative Biology, University of South Florida, Science Center 110, Tampa, FL 33620, USA
| | - Holly J Kilvitis
- Department of Integrative Biology, University of South Florida, Science Center 110, Tampa, FL 33620, USA
| | - Lynn B Martin
- Department of Integrative Biology, University of South Florida, Science Center 110, Tampa, FL 33620, USA
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