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Dziuba MK, McIntire KM, Seto K, Davenport ES, Rogalski MA, Gowler CD, Baird E, Vaandrager M, Huerta C, Jaye R, Corcoran FE, Withrow A, Ahrendt S, Salamov A, Nolan M, Tejomurthula S, Barry K, Grigoriev IV, James TY, Duffy MA. Phylogeny, morphology, virulence, ecology, and host range of Ordospora pajunii (Ordosporidae), a microsporidian symbiont of Daphnia spp. mBio 2024; 15:e0058224. [PMID: 38651867 DOI: 10.1128/mbio.00582-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 03/20/2024] [Indexed: 04/25/2024] Open
Abstract
The impacts of microsporidia on host individuals are frequently subtle and can be context dependent. A key example of the latter comes from a recently discovered microsporidian symbiont of Daphnia, the net impact of which was found to shift from negative to positive based on environmental context. Given this, we hypothesized low baseline virulence of the microsporidian; here, we investigated the impact of infection on hosts in controlled conditions and the absence of other stressors. We also investigated its phylogenetic position, ecology, and host range. The genetic data indicate that the symbiont is Ordospora pajunii, a newly described microsporidian parasite of Daphnia. We show that O. pajunii infection damages the gut, causing infected epithelial cells to lose microvilli and then rupture. The prevalence of this microsporidian could be high (up to 100% in the lab and 77% of adults in the field). Its overall virulence was low in most cases, but some genotypes suffered reduced survival and/or reproduction. Susceptibility and virulence were strongly host-genotype dependent. We found that North American O. pajunii were able to infect multiple Daphnia species, including the European species Daphnia longispina, as well as Ceriodaphnia spp. Given the low, often undetectable virulence of this microsporidian and potentially far-reaching consequences of infections for the host when interacting with other pathogens or food, this Daphnia-O. pajunii symbiosis emerges as a valuable system for studying the mechanisms of context-dependent shifts between mutualism and parasitism, as well as for understanding how symbionts might alter host interactions with resources. IMPORTANCE The net outcome of symbiosis depends on the costs and benefits to each partner. Those can be context dependent, driving the potential for an interaction to change between parasitism and mutualism. Understanding the baseline fitness impact in an interaction can help us understand those shifts; for an organism that is generally parasitic, it should be easier for it to become a mutualist if its baseline virulence is relatively low. Recently, a microsporidian was found to become beneficial to its Daphnia hosts in certain ecological contexts, but little was known about the symbiont (including its species identity). Here, we identify it as the microsporidium Ordospora pajunii. Despite the parasitic nature of microsporidia, we found O. pajunii to be, at most, mildly virulent; this helps explain why it can shift toward mutualism in certain ecological contexts and helps establish O. pajunii is a valuable model for investigating shifts along the mutualism-parasitism continuum.
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Affiliation(s)
- Marcin K Dziuba
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kristina M McIntire
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kensuke Seto
- Faculty of Environment and Information Sciences, Yokohama National University, Yokohama, Kanagawa, Japan
| | - Elizabeth S Davenport
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Mary A Rogalski
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
- Biology Department, Bowdoin College, Brunswick, Maine, USA
| | - Camden D Gowler
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Emma Baird
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Megan Vaandrager
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Cristian Huerta
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Riley Jaye
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Fiona E Corcoran
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Alicia Withrow
- Center for Advanced Microscopy, Michigan State University, East Lansing, Michigan, USA
| | - Steven Ahrendt
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Asaf Salamov
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Matt Nolan
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Sravanthi Tejomurthula
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Kerrie Barry
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Igor V Grigoriev
- United States Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, California, USA
| | - Timothy Y James
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Meghan A Duffy
- Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
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2
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Butterworth NJ, Heffernan L, Hall MD. Is there a sicker sex? Dose relationships modify male-female differences in infection prevalence. Proc Biol Sci 2024; 291:20232575. [PMID: 38196362 PMCID: PMC10777155 DOI: 10.1098/rspb.2023.2575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 12/04/2023] [Indexed: 01/11/2024] Open
Abstract
Throughout the animal kingdom, there are striking differences in the propensity of one sex or the other to become infected. However, precisely when we should expect males or females to be the sicker sex remains unclear. A major barrier to answering this question is that very few studies have considered how the susceptibility of males and females changes across the full range of pathogen doses encountered in nature. Without quantifying this 'dose-susceptibility' relationship, we have likely underestimated the scope for sex differences to arise. Here, we use the Daphnia magnia-Pasteuria ramosa system to reveal that sex differences in susceptibility are entirely dose-dependent, with pathogens having a higher probability of successfully establishing an infection in mature males at low doses, but mature females at high doses. The scope for male-female differences to emerge is therefore much greater than previously appreciated-extending to sex differences in the upper limits to infection success, per-propagule infectivity risks and density-dependent pathogen behaviour. Applying this expanded scope across the animal kingdom will help us understand when and why a sicker sex emerges, and the implications for diseases in nature-where sex ratios, age structure and pathogen densities vary drastically.
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Affiliation(s)
- Nathan J. Butterworth
- School of Biological Sciences, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| | - Lindsey Heffernan
- School of Biological Sciences, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| | - Matthew D. Hall
- School of Biological Sciences, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
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3
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Claar DC, Faiad SM, Mastick NC, Welicky RL, Williams MA, Sasser KT, Weber JN, Wood CL. Estimating the magnitude and sensitivity of energy fluxes for stickleback hosts and Schistocephalus solidus parasites using the metabolic theory of ecology. Ecol Evol 2023; 13:e10755. [PMID: 38053794 PMCID: PMC10694383 DOI: 10.1002/ece3.10755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 11/03/2023] [Accepted: 11/09/2023] [Indexed: 12/07/2023] Open
Abstract
Parasites are ubiquitous, yet their effects on hosts are difficult to quantify and generalize across ecosystems. One promising metric of parasitic impact uses the metabolic theory of ecology (MTE) to calculate energy flux, an estimate of energy lost to parasites. We investigated the feasibility of using metabolic scaling rules to compare the energetic burden of parasitism among individuals. Specifically, we found substantial sensitivity of energy flux estimates to input parameters used in the MTE equation when using available data from a model host-parasite system (Gasterosteus aculeatus and Schistocephalus solidus). Using literature values, size data from parasitized wild fish, and a respirometry experiment, we estimate that a single S. solidus tapeworm may extract up to 32% of its stickleback host's baseline metabolic energy requirement, and that parasites in multiple infections may collectively extract up to 46%. The amount of energy siphoned from stickleback to tapeworms is large but did not instigate an increase in respiration rate in the current study. This emphasizes the importance of future work focusing on how parasites influence ecosystem energetics. The approach of using the MTE to calculate energy flux provides great promise as a quantitative foundation for such estimates and provides a more concrete metric of parasite impact on hosts than parasite abundance alone.
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Affiliation(s)
- Danielle C. Claar
- Washington State Department of Natural ResourcesOlympiaWashingtonUSA
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Sara M. Faiad
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Natalie C. Mastick
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Rachel L. Welicky
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
- Unit for Environmental Sciences and ManagementNorth‐West UniversityPotchefstroomSouth Africa
- College of Arts and SciencesNeumann UniversityAstonPennsylvaniaUSA
| | - Maureen A. Williams
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
- Biology DepartmentMcDaniel CollegeWestminsterMarylandUSA
| | - Kristofer T. Sasser
- Department of Biological SciencesUniversity of Alaska AnchorageAnchorageAlaskaUSA
- Department of Integrative BiologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - Jesse N. Weber
- Department of Biological SciencesUniversity of Alaska AnchorageAnchorageAlaskaUSA
- Department of Integrative BiologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - Chelsea L. Wood
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
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Aleuy OA, Peacock SJ, Molnár PK, Ruckstuhl KE, Kutz SJ. Local thermal adaptation and local temperature regimes drive the performance of a parasitic helminth under climate change: The case of Marshallagia marshalli from wild ungulates. GLOBAL CHANGE BIOLOGY 2023; 29:6217-6233. [PMID: 37615247 DOI: 10.1111/gcb.16918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 08/25/2023]
Abstract
Across a species' range, populations are exposed to their local thermal environments, which on an evolutionary scale, may cause adaptative differences among populations. Helminths often have broad geographic ranges and temperature-sensitive life stages but little is known about whether and how local thermal adaptation can influence their response to climate change. We studied the thermal responses of the free-living stages of Marshallagia marshalli, a parasitic nematode of wild ungulates, along a latitudinal gradient. We first determine its distribution in wild sheep species in North America. Then we cultured M. marshalli eggs from different locations at temperatures from 5 to 38°C. We fit performance curves based on the metabolic theory of ecology to determine whether development and mortality showed evidence of local thermal adaptation. We used parameter estimates in life-cycle-based host-parasite models to understand how local thermal responses may influence parasite performance under general and location-specific climate-change projections. We found that M. marshalli has a wide latitudinal and host range, infecting wild sheep species from New Mexico to Yukon. Increases in mortality and development time at higher temperatures were most evident for isolates from northern locations. Accounting for location-specific parasite parameters primarily influenced the magnitude of climate change parasite performance, while accounting for location-specific climates primarily influenced the phenology of parasite performance. Despite differences in development and mortality among M. marshalli populations, when using site-specific climate change projections, there was a similar magnitude of impact on the relative performance of M. marshalli among populations. Climate change is predicted to decrease the expected lifetime reproductive output of M. marshalli in all populations while delaying its seasonal peak by approximately 1 month. Our research suggests that accurate projections of the impacts of climate change on broadly distributed species need to consider local adaptations of organisms together with local temperature profiles and climate projections.
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Affiliation(s)
- O Alejandro Aleuy
- Department of Biological Sciences, University of Calgary, Alberta, Calgary, Canada
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Alberta, Calgary, Canada
| | - Stephanie J Peacock
- Department of Biological Sciences, University of Calgary, Alberta, Calgary, Canada
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Alberta, Calgary, Canada
| | - Péter K Molnár
- Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, Toronto, Canada
- Department of Biological Sciences, University of Toronto Scarborough, Ontario, Toronto, Canada
| | - Kathreen E Ruckstuhl
- Department of Biological Sciences, University of Calgary, Alberta, Calgary, Canada
| | - Susan J Kutz
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Alberta, Calgary, Canada
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5
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Krichel L, Kirk D, Pencer C, Hönig M, Wadhawan K, Krkošek M. Short-term temperature fluctuations increase disease in a Daphnia-parasite infectious disease system. PLoS Biol 2023; 21:e3002260. [PMID: 37683040 PMCID: PMC10491407 DOI: 10.1371/journal.pbio.3002260] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 07/18/2023] [Indexed: 09/10/2023] Open
Abstract
Climate change has profound effects on infectious disease dynamics, yet the impacts of increased short-term temperature fluctuations on disease spread remain poorly understood. We empirically tested the theoretical prediction that short-term thermal fluctuations suppress endemic infection prevalence at the pathogen's thermal optimum. This prediction follows from a mechanistic disease transmission model analyzed using stochastic simulations of the model parameterized with thermal performance curves (TPCs) from metabolic scaling theory and using nonlinear averaging, which predicts ecological outcomes consistent with Jensen's inequality (i.e., reduced performance around concave-down portions of a thermal response curve). Experimental observations of replicated epidemics of the microparasite Ordospora colligata in Daphnia magna populations indicate that temperature variability had the opposite effect of our theoretical predictions and instead increase endemic infection prevalence. This positive effect of temperature variability is qualitatively consistent with a published hypothesis that parasites may acclimate more rapidly to fluctuating temperatures than their hosts; however, incorporating hypothetical effects of delayed host acclimation into the mechanistic transmission model did not fully account for the observed pattern. The experimental data indicate that shifts in the distribution of infection burden underlie the positive effect of temperature fluctuations on endemic prevalence. The increase in disease risk associated with climate fluctuations may therefore result from disease processes interacting across scales, particularly within-host dynamics, that are not captured by combining standard transmission models with metabolic scaling theory.
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Affiliation(s)
- Leila Krichel
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Devin Kirk
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Clara Pencer
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Madison Hönig
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
- Department of Anthropology, Washington State University, Pullman, Washington, United States of America
| | - Kiran Wadhawan
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
- School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Martin Krkošek
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
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6
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Manzi F, Schlösser P, Owczarz A, Wolinska J. Polystyrene nanoplastics differentially influence the outcome of infection by two microparasites of the host Daphnia magna. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220013. [PMID: 36744559 PMCID: PMC9900706 DOI: 10.1098/rstb.2022.0013] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The accumulation of micro- and nanoplastic particles in freshwater bodies has given rise to much concern regarding their potential adverse effects on aquatic biota. Beyond their known effects on single species, recent experimental evidence suggests that host-parasite interactions can also be affected by environmental concentrations of micro- and nanoplastics. However, investigating the effects of contaminants in simplified infection settings (i.e. one host, one parasite) may understate their ecological relevance, considering that co-infections are common in nature. We exposed the cladoceran Daphnia magna to a fungal parasite of the haemolymph (Metschnikowia bicuspidata) and a gut microsporidium (Ordospora colligata), either in single or co-infection. In addition, Daphnia were raised individually in culture media containing 0, 5 or 50 mg l-1 of polystyrene nanoplastic beads (100 nm). Only few infections were successful at the higher nanoplastic concentration, due to increased mortality of the host. While no significant effect of the low concentration was detected on the microsporidium, the proportion of hosts infected by the fungal parasite increased dramatically, leading to more frequent co-infections under nanoplastic exposure. These results indicate that nanoplastics can affect the performance of distinct pathogens in diverging ways, with the potential to favour parasite coexistence in a common zooplanktonic host. This article is part of the theme issue 'Infectious disease ecology and evolution in a changing world'.
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Affiliation(s)
- Florent Manzi
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, 12587 Berlin, Germany
| | - Paula Schlösser
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, 12587 Berlin, Germany,Department of Biology, Chemistry, Pharmacy, Institute of Biology, Freie Universität Berlin, 14195 Berlin, Germany
| | - Agata Owczarz
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, 12587 Berlin, Germany
| | - Justyna Wolinska
- Department of Evolutionary and Integrative Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, 12587 Berlin, Germany,Department of Biology, Chemistry, Pharmacy, Institute of Biology, Freie Universität Berlin, 14195 Berlin, Germany
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7
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Angst P, Ebert D, Fields PD. Population genetic analysis of the microsporidium Ordospora colligata reveals the role of natural selection and phylogeography on its extremely compact and reduced genome. G3 (BETHESDA, MD.) 2023; 13:jkad017. [PMID: 36655395 PMCID: PMC9997559 DOI: 10.1093/g3journal/jkad017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 01/02/2023] [Accepted: 01/11/2023] [Indexed: 01/20/2023]
Abstract
The determinants of variation in a species' genome-wide nucleotide diversity include historical, environmental, and stochastic aspects. This diversity can inform us about the species' past and present evolutionary dynamics. In parasites, the mode of transmission and the interactions with the host might supersede the effects of these aspects in shaping parasite genomic diversity. We used genomic samples from 10 populations of the microsporidian parasite Ordospora colligata to investigate present genomic diversity and how it was shaped by evolutionary processes, specifically, the role of phylogeography, co-phylogeography (with the host), natural selection, and transmission mode. Although very closely related microsporidia cause diseases in humans, O. colligata is specific to the freshwater crustacean Daphnia magna and has one of the smallest known eukaryotic genomes. We found an overlapping phylogeography between O. colligata and its host highlighting the long-term, intimate relationship between them. The observed geographic distribution reflects previous findings that O. colligata exhibits adaptations to colder habitats, which differentiates it from other microsporidian gut parasites of D. magna predominantly found in warmer areas. The co-phylogeography allowed us to calibrate the O. colligata phylogeny and thus estimate its mutation rate. We identified several genetic regions under potential selection. Our whole-genome study provides insights into the evolution of one of the most reduced eukaryotic genomes and shows how different processes shape genomic diversity of an obligate parasite.
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Affiliation(s)
- Pascal Angst
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
| | - Peter D Fields
- Department of Environmental Sciences, Zoology, University of Basel, Basel 4051, Switzerland
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Ameline C, Voegtli F, Andras J, Dexter E, Engelstädter J, Ebert D. Genetic slippage after sex maintains diversity for parasite resistance in a natural host population. SCIENCE ADVANCES 2022; 8:eabn0051. [PMID: 36399570 PMCID: PMC9674289 DOI: 10.1126/sciadv.abn0051] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
Although parasite-mediated selection is a major driver of host evolution, its influence on genetic variation for parasite resistance is not yet well understood. We monitored resistance in a large population of the planktonic crustacean Daphnia magna over 8 years, as it underwent yearly epidemics of the bacterial pathogen Pasteuria ramosa. We observed cyclic dynamics of resistance: Resistance increased throughout the epidemics, but susceptibility was restored each spring when hosts hatched from sexual resting stages. Host resting stages collected across the year showed that largely resistant host populations can produce susceptible sexual offspring. A genetic model of resistance developed for this host-parasite system, based on multiple loci and strong epistasis, is in partial agreement with our findings. Our results reveal that, despite strong selection for resistance in a natural host population, genetic slippage after sexual reproduction can be a strong factor for the maintenance of genetic diversity of host resistance.
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Affiliation(s)
- Camille Ameline
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| | - Felix Voegtli
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| | - Jason Andras
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| | - Eric Dexter
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| | - Jan Engelstädter
- School of Biological Sciences, The University of Queensland, Brisbane, Australia
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
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Kirk D, O’Connor MI, Mordecai EA. Scaling effects of temperature on parasitism from individuals to populations. J Anim Ecol 2022; 91:2087-2102. [PMID: 35900837 PMCID: PMC9532350 DOI: 10.1111/1365-2656.13786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/15/2022] [Indexed: 11/27/2022]
Abstract
Parasitism is expected to change in a warmer future, but whether warming leads to substantial increases in parasitism remains unclear. Understanding how warming effects on parasitism in individual hosts (e.g. parasite load) translate to effects on population-level parasitism (e.g. prevalence, R0 ) remains a major knowledge gap. We conducted a literature review and identified 24 host-parasite systems that had information on the temperature dependence of parasitism at both individual host and host population levels: 13 vector-borne systems and 11 environmentally transmitted systems. We found a strong positive correlation between the thermal optima of individual- and population-level parasitism, although several of the environmentally transmitted systems exhibited thermal optima >5°C apart between individual and population levels. Parasitism thermal optima were close to vector performance thermal optima in vector-borne systems but not hosts in environmentally transmitted systems, suggesting these thermal mismatches may be more common in certain types of host-parasite systems. We also adapted and simulated simple models for both types of transmission modes and found the same pattern across the two modes: thermal optima were more strongly correlated across scales when there were more traits linking individual- to population-level processes. Generally, our results suggest that information on the temperature dependence, and specifically the thermal optimum, at either the individual or population level should provide a useful-although not quantitatively exact-baseline for predicting temperature dependence at the other level, especially in vector-borne parasite systems. Environmentally transmitted parasitism may operate by a different set of rules, in which temperature dependence is decoupled in some systems, requiring the need for trait-based studies of temperature dependence at individual and population levels.
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Affiliation(s)
- Devin Kirk
- Department of Biology, Stanford University, Stanford, USA
- Department of Zoology, University of British Columbia, Vancouver, Canada
| | - Mary I. O’Connor
- Department of Zoology, University of British Columbia, Vancouver, Canada
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10
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Ebert D. Daphnia as a versatile model system in ecology and evolution. EvoDevo 2022; 13:16. [PMID: 35941607 PMCID: PMC9360664 DOI: 10.1186/s13227-022-00199-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 06/20/2022] [Indexed: 11/10/2022] Open
Abstract
Water fleas of the genus Daphnia have been a model system for hundreds of years and is among the best studied ecological model organisms to date. Daphnia are planktonic crustaceans with a cyclic parthenogenetic life-cycle. They have a nearly worldwide distribution, inhabiting standing fresh- and brackish water bodies, from small temporary pools to large lakes. Their predominantly asexual reproduction allows for the study of phenotypes excluding genetic variation, enabling us to separate genetic from non-genetic effects. Daphnia are often used in studies related to ecotoxicology, predator-induced defence, host–parasite interactions, phenotypic plasticity and, increasingly, in evolutionary genomics. The most commonly studied species are Daphnia magna and D. pulex, for which a rapidly increasing number of genetic and genomic tools are available. Here, I review current research topics, where the Daphnia model system plays a critical role.
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Affiliation(s)
- Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, CH-4051, Basel, Switzerland.
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11
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Peacock SJ, Kutz SJ, Hoar BM, Molnár PK. Behaviour is more important than thermal performance for an Arctic host-parasite system under climate change. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220060. [PMID: 36016913 PMCID: PMC9399711 DOI: 10.1098/rsos.220060] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 08/02/2022] [Indexed: 05/10/2023]
Abstract
Climate change is affecting Arctic ecosystems, including parasites. Predicting outcomes for host-parasite systems is challenging due to the complexity of multi-species interactions and the numerous, interacting pathways by which climate change can alter dynamics. Increasing temperatures may lead to faster development of free-living parasite stages but also higher mortality. Interactions between behavioural plasticity of hosts and parasites will also influence transmission processes. We combined laboratory experiments and population modelling to understand the impacts of changing temperatures on barren-ground caribou (Rangifer tarandus) and their common helminth (Ostertagia gruehneri). We experimentally determined the thermal performance curves for mortality and development of free-living parasite stages and applied them in a spatial host-parasite model that also included behaviour of the parasite (propensity for arrested development in the host) and host (long-distance migration). Sensitivity analyses showed that thermal responses had less of an impact on simulated parasite burdens than expected, and the effect differed depending on parasite behaviour. The propensity for arrested development and host migration led to distinct spatio-temporal patterns in infection. These results emphasize the importance of considering behaviour-and behavioural plasticity-when projecting climate-change impacts on host-parasite systems.
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Affiliation(s)
- Stephanie J. Peacock
- Department of Ecosystem and Public Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB Canada, T2N 4Z6
- Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON Canada, M1C 1A4
| | - Susan J. Kutz
- Department of Ecosystem and Public Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB Canada, T2N 4Z6
| | - Bryanne M. Hoar
- Department of Ecosystem and Public Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB Canada, T2N 4Z6
| | - Péter K. Molnár
- Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON Canada, M1C 1A4
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON Canada, M5S 3B2
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Kunze C, Luijckx P, Jackson AL, Donohue I. Alternate patterns of temperature variation bring about very different disease outcomes at different mean temperatures. eLife 2022; 11:72861. [PMID: 35164901 PMCID: PMC8846586 DOI: 10.7554/elife.72861] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 01/05/2022] [Indexed: 02/01/2023] Open
Abstract
The dynamics of host-parasite interactions are highly temperature-dependent and may be modified by increasing frequency and intensity of climate-driven heat events. Here, we show that altered patterns of temperature variance lead to an almost order-of-magnitude shift in thermal performance of host and pathogen life-history traits over and above the effects of mean temperature and, moreover, that different temperature regimes affect these traits differently. We found that diurnal fluctuations of ±3°C lowered infection rates and reduced spore burden compared to constant temperatures in our focal host Daphnia magna exposed to the microsporidium parasite Ordospora colligata. In contrast, a 3-day heatwave (+6°C) did not affect infection rates, but increased spore burden (relative to constant temperatures with the same mean) at 16°C, while reducing burden at higher temperatures. We conclude that changing patterns of climate variation, superimposed on shifts in mean temperatures due to global warming, may have profound and unanticipated effects on disease dynamics. Global warming is increasing average temperatures and causing extreme temperature fluctuations and heatwaves. These changes may affect when, where, and how often infectious disease outbreaks occur. This could have profound impacts on agriculture, human health, and wildlife. Studying how extreme temperatures or temperature fluctuations alter infections in laboratory animals may help scientists to better understand the impact of climate change on disease. A small aquatic invertebrate, such as a water flea, is one good candidate for such studies. These tiny creatures can be grown in small glass jars in temperature-controlled aquariums. Kunze, Luijckx et al. show that temperature fluctuations and heat waves have complex effects on parasitic infections in water fleas. In the experiments, water fleas housed with a parasite that infects them were exposed to constant temperatures, fluctuating temperatures, or three-day heatwaves, while being kept at a broad range of mean water temperatures. Then, Kunze, Luijckx et al. measured how these conditions affected the water fleas’ longevity, reproduction, and parasite infections. This revealed that temperature variations had a unique effect on the life span, and reproduction and infection rates of the water fleas, depending on the average water temperature the animals were kept at. Heatwaves drastically increased the number of parasites in the water fleas at an average water temperature of 16 °C but had no effect at all or decreased the number of parasites at 19 °C and 22 °C, respectively. Similarly, at high average water temperatures (>24 °C), temperature fluctuations reduced the number of water fleas infected with parasites and the number of parasites in each infected flea. Moreover, the maximum temperature at which parasites were able to cause infections was 5 °C lower under fluctuating temperatures than under constant temperatures. Kunze and Luijckx et al. show that consistent high temperatures, temperature changes, extreme weather events, and mean water temperature affect disease outcomes in water fleas. More studies are needed to assess how temperature variations change the course of diseases in other organisms and to understand the underlying mechanisms. Learning more about disease-temperature interactions will help scientists predict climate change-driven disease outbreaks.
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Affiliation(s)
- Charlotte Kunze
- Institute for Chemistry and Biology of the Marine Environment [ICBM], Carl von Ossietzky University of Oldenburg, Oldenburg, Germany.,Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Pepijn Luijckx
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Andrew L Jackson
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Ian Donohue
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
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13
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Sequential infection of Daphnia magna by a gut microsporidium followed by a haemolymph yeast decreases transmission of both parasites. Parasitology 2021; 148:1566-1577. [PMID: 35060463 PMCID: PMC8564772 DOI: 10.1017/s0031182021001384] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Over the course of seasonal epidemics, populations of susceptible hosts may encounter a wide variety of parasites. Parasite phenology affects the order in which these species encounter their hosts, leading to sequential infections, with potentially strong effects on within-host growth and host population dynamics. Here, the cladoceran Daphnia magna was exposed sequentially to a haemolymph-infecting yeast (Metschnikowia bicuspidata) and a gut microsporidium (Ordospora colligata), with experimental treatments reflecting two possible scenarios of parasite succession. The effects of single and co-exposure were compared on parasite infectivity, spore production and the overall virulence experienced by the host. We show that neither parasite benefited from coinfection; instead, when hosts encountered Ordospora, followed by Metschnikowia, higher levels of host mortality contributed to an overall decrease in the transmission of both parasites. These results showcase an example of sequential infections generating unilateral priority effects, in which antagonistic interactions between parasites can alleviate the intensity of infection and coincide with maladaptive levels of damage inflicted on the host.
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14
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Mahmoud NM, Mahmoud MH, Alamery S, Fouad H. Structural modeling and phylogenetic analysis for infectious disease transmission pattern based on maximum likelihood tree approach. JOURNAL OF AMBIENT INTELLIGENCE AND HUMANIZED COMPUTING 2021; 12:3479-3492. [PMID: 33425052 PMCID: PMC7778505 DOI: 10.1007/s12652-020-02702-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
The contagious disease transmission pattern outbreak caused a massive human casualty and became a pandemic, as confirmed by the World Health Organization (WHO). The present research aims to understand the infectious disease transmission pattern outbreak due to molecular epidemiology. Hence, infected patients over time can spread infectious disease. The virus may develop further mutations, and that there might be a more toxic virulent strain, which leads to several environmental risk factors. Therefore, it is essential to monitor and characterize patient profiles, variants, symptoms, geographic locations, and treatment responses to analyze and evaluate infectious disease patterns among humans. This research proposes the Evolutionary tree analysis (ETA) for the molecular evolutionary genetic analysis to reduce medical risk factors. Furthermore, The Maximum likelihood tree method (MLTM) has been used to analyze the selective pressure, which is examined to identify a mutation that may influence the infectious disease transmission pattern's clinical progress. This study also utilizes ETA with Markov Chain Bayesian Statistics (MCBS) approach to reconstruct transmission trees with sequence information. The experimental shows that the proposed ETA-MCBS method achieves a 97.55% accuracy, prediction of 99.56%, and 98.55% performance compared to other existing methods.
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Affiliation(s)
- Nourelhoda M. Mahmoud
- Biomedical Engineering Department, Faculty of Engineering, Minia University, Minia, Egypt
| | - Mohamed H. Mahmoud
- Department of Biochemistry, College of Science, King Saud University, PO Box 22452, Riyadh, 11451 Saudi Arabia
| | - Salman Alamery
- Department of Biochemistry, College of Science, King Saud University, PO Box 22452, Riyadh, 11451 Saudi Arabia
| | - Hassan Fouad
- Biomedical Engineering Department, Faculty of Engineering, Helwan University, Cairo, Egypt
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15
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Abstract
Climate change is expected to have complex effects on infectious diseases, causing some to increase, others to decrease, and many to shift their distributions. There have been several important advances in understanding the role of climate and climate change on wildlife and human infectious disease dynamics over the past several years. This essay examines 3 major areas of advancement, which include improvements to mechanistic disease models, investigations into the importance of climate variability to disease dynamics, and understanding the consequences of thermal mismatches between host and parasites. Applying the new information derived from these advances to climate-disease models and addressing the pressing knowledge gaps that we identify should improve the capacity to predict how climate change will affect disease risk for both wildlife and humans.
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Affiliation(s)
- Jason R. Rohr
- Department of Biological Sciences, Environmental Change Initiative, Eck Institute of Global Health, University of Notre Dame, Notre Dame, Indiana, United States of America
- * E-mail:
| | - Jeremy M. Cohen
- Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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16
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Kirk D, Luijckx P, Jones N, Krichel L, Pencer C, Molnár P, Krkošek M. Experimental evidence of warming-induced disease emergence and its prediction by a trait-based mechanistic model. Proc Biol Sci 2020; 287:20201526. [PMID: 33049167 DOI: 10.1098/rspb.2020.1526] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Predicting the effects of seasonality and climate change on the emergence and spread of infectious disease remains difficult, in part because of poorly understood connections between warming and the mechanisms driving disease. Trait-based mechanistic models combined with thermal performance curves arising from the metabolic theory of ecology (MTE) have been highlighted as a promising approach going forward; however, this framework has not been tested under controlled experimental conditions that isolate the role of gradual temporal warming on disease dynamics and emergence. Here, we provide experimental evidence that a slowly warming host-parasite system can be pushed through a critical transition into an epidemic state. We then show that a trait-based mechanistic model with MTE functional forms can predict the critical temperature for disease emergence, subsequent disease dynamics through time and final infection prevalence in an experimentally warmed system of Daphnia and a microsporidian parasite. Our results serve as a proof of principle that trait-based mechanistic models using MTE subfunctions can predict warming-induced disease emergence in data-rich systems-a critical step towards generalizing the approach to other systems.
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Affiliation(s)
- Devin Kirk
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Pepijn Luijckx
- School of Natural Sciences, Zoology Department, Trinity College Dublin, University of Dublin, Dublin, Republic of Ireland
| | - Natalie Jones
- School of Biological Sciences, University of Queensland, Brisbane, Australia
| | - Leila Krichel
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Clara Pencer
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Péter Molnár
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada.,Laboratory of Quantitative Global Change Ecology, Department of Biological Sciences, University of Toronto Scarborough, Toronto, Canada
| | - Martin Krkošek
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
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17
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Haag KL, Pombert JF, Sun Y, de Albuquerque NRM, Batliner B, Fields P, Lopes TF, Ebert D. Microsporidia with Vertical Transmission Were Likely Shaped by Nonadaptive Processes. Genome Biol Evol 2020; 12:3599-3614. [PMID: 31825473 PMCID: PMC6944219 DOI: 10.1093/gbe/evz270] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2019] [Indexed: 12/14/2022] Open
Abstract
Microsporidia have the leanest genomes among eukaryotes, and their physiological and genomic simplicity has been attributed to their intracellular, obligate parasitic life-style. However, not all microsporidia genomes are small or lean, with the largest dwarfing the smallest ones by at least an order of magnitude. To better understand the evolutionary mechanisms behind this genomic diversification, we explore here two clades of microsporidia with distinct life histories, Ordospora and Hamiltosporidium, parasitizing the same host species, Daphnia magna. Based on seven newly assembled genomes, we show that mixed-mode transmission (the combination of horizontal and vertical transmission), which occurs in Hamiltosporidium, is found to be associated with larger and AT-biased genomes, more genes, and longer intergenic regions, as compared with the exclusively horizontally transmitted Ordospora. Furthermore, the Hamiltosporidium genome assemblies contain a variety of repetitive elements and long segmental duplications. We show that there is an excess of nonsynonymous substitutions in the microsporidia with mixed-mode transmission, which cannot be solely attributed to the lack of recombination, suggesting that bursts of genome size in these microsporidia result primarily from genetic drift. Overall, these findings suggest that the switch from a horizontal-only to a mixed mode of transmission likely produces population bottlenecks in Hamiltosporidium species, therefore reducing the effectiveness of natural selection, and allowing their genomic features to be largely shaped by nonadaptive processes.
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Affiliation(s)
- Karen L Haag
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Yukun Sun
- Department of Biology, Illinois Institute of Technology
| | - Nathalia Rammé M de Albuquerque
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Peter Fields
- Department of Environmental Sciences, Zoology, Basel University, Switzerland
| | - Tiago Falcon Lopes
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, Basel University, Switzerland
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18
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Cator LJ, Johnson LR, Mordecai EA, Moustaid FE, Smallwood TRC, LaDeau SL, Johansson MA, Hudson PJ, Boots M, Thomas MB, Power AG, Pawar S. The Role of Vector Trait Variation in Vector-Borne Disease Dynamics. Front Ecol Evol 2020; 8:189. [PMID: 32775339 PMCID: PMC7409824 DOI: 10.3389/fevo.2020.00189] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Many important endemic and emerging diseases are transmitted by vectors that are biting arthropods. The functional traits of vectors can affect pathogen transmission rates directly and also through their effect on vector population dynamics. Increasing empirical evidence shows that vector traits vary significantly across individuals, populations, and environmental conditions, and at time scales relevant to disease transmission dynamics. Here, we review empirical evidence for variation in vector traits and how this trait variation is currently incorporated into mathematical models of vector-borne disease transmission. We argue that mechanistically incorporating trait variation into these models, by explicitly capturing its effects on vector fitness and abundance, can improve the reliability of their predictions in a changing world. We provide a conceptual framework for incorporating trait variation into vector-borne disease transmission models, and highlight key empirical and theoretical challenges. This framework provides a means to conceptualize how traits can be incorporated in vector borne disease systems, and identifies key areas in which trait variation can be explored. Determining when and to what extent it is important to incorporate trait variation into vector borne disease models remains an important, outstanding question.
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Affiliation(s)
- Lauren J. Cator
- Department of Life Sciences, Imperial College London, Ascot, United Kingdom
| | - Leah R. Johnson
- Department of Statistics, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Erin A. Mordecai
- Department of Biology, Stanford University, Stanford, CA, United States
| | - Fadoua El Moustaid
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
- BresMed America Inc, Las Vegas, NV, United States
| | | | - Shannon L. LaDeau
- The Cary Institute of Ecosystem Studies, Millbrook, NY, United States
| | | | - Peter J. Hudson
- Center for Infectious Disease Dynamics and Department of Biology, Pennsylvania State University, University Park, PA, United States
| | - Michael Boots
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Matthew B. Thomas
- Department of Entomology, Pennsylvania State University, University Park, PA, United States
| | - Alison G. Power
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, United States
| | - Samraat Pawar
- Department of Life Sciences, Imperial College London, Ascot, United Kingdom
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19
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Zukowski N, Kirk D, Wadhawan K, Shea D, Start D, Krkošek M. Predators can influence the host-parasite dynamics of their prey via nonconsumptive effects. Ecol Evol 2020; 10:6714-6722. [PMID: 32724544 PMCID: PMC7381593 DOI: 10.1002/ece3.6401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 04/04/2020] [Accepted: 04/29/2020] [Indexed: 12/18/2022] Open
Abstract
Ecological communities are partly structured by indirect interactions, where one species can indirectly affect another by altering its interactions with a third species. In the absence of direct predation, nonconsumptive effects of predators on prey have important implications for subsequent community interactions. To better understand these interactions, we used a Daphnia-parasite-predator cue system to evaluate if predation risk affects Daphnia responses to a parasite. We investigated the effects of predator cues on two aspects of host-parasite interactions (susceptibility to infection and infection intensity), and whether or not these effects differed between sexes. Our results show that changes in response to predator cues caused an increase in the prevalence and intensity of parasite infections in female predator-exposed Daphnia. Importantly, the magnitude of infection risk depended on how long Daphnia were exposed to the cues. Additionally, heavily infected Daphnia that were constantly exposed to cues produced relatively more offspring. While males were ~5× less likely to become infected compared to females, we were unable to detect effects of predator cues on male Daphnia-parasite interactions. In sum, predators, prey, and their parasites can form complex subnetworks in food webs, necessitating a nuanced understanding of how nonconsumptive effects may mediate these interactions.
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Affiliation(s)
- Nicolette Zukowski
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoONCanada
- School of Public Health, University of CaliforniaBerkeleyCAUSA
| | - Devin Kirk
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoONCanada
- Department of BiologyStanford UniversityStanfordCAUSA
| | - Kiran Wadhawan
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoONCanada
| | - Dylan Shea
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoONCanada
| | - Denon Start
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoONCanada
- Center for Population BiologyUniversity of CaliforniaDavisCAUSA
| | - Martin Krkošek
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoONCanada
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20
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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: 253] [Impact Index Per Article: 50.6] [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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