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Sun D, Ellepola G, Herath J, Meegaskumbura M. Ecological Barriers for an Amphibian Pathogen: A Narrow Ecological Niche for Batrachochytrium salamandrivorans in an Asian Chytrid Hotspot. J Fungi (Basel) 2023; 9:911. [PMID: 37755019 PMCID: PMC10532633 DOI: 10.3390/jof9090911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/02/2023] [Accepted: 09/05/2023] [Indexed: 09/28/2023] Open
Abstract
The chytrid fungal pathogens Batrachochytrium salamandrivorans (Bsal) and B. dendrobatidis (Bd) are driving amphibian extinctions and population declines worldwide. As their origins are believed to be in East/Southeast Asia, this region is crucial for understanding their ecology. However, Bsal screening is relatively limited in this region, particularly in hotspots where Bd lineage diversity is high. To address this gap, we conducted an extensive Bsal screening involving 1101 individuals from 36 amphibian species, spanning 17 natural locations and four captive facilities in the biodiversity-rich Guangxi Zhuang Autonomous Region (GAR). Our PCR assays yielded unexpected results, revealing the complete absence of Bsal in all tested samples including 51 individuals with Bd presence. To understand the potential distribution of Bsal, we created niche models, utilizing existing occurrence records from both Asia and Europe. These models estimated potential suitable habitats for Bsal largely in the northern and southwestern parts of the GAR. Although Bsal was absent in our samples, the niche models identified 10 study sites as being potentially suitable for this pathogen. Interestingly, out of these 10 sites, Bd was detected at 8. This suggests that Bsal and Bd could possibly co-exist in these habitats, if Bsal were present. Several factors seem to influence the distribution of Bsal in Asia, including variations in temperature, local caudate species diversity, elevation, and human population density. However, it is climate-related factors that hold the greatest significance, accounting for a notable 60% contribution. The models propose that the specific climatic conditions of arid regions, primarily seen in the GAR, play a major role in the distribution of Bsal. Considering the increased pathogenicity of Bsal at stable and cooler temperatures (10-15 °C), species-dependent variations, and the potential for seasonal Bd-Bsal interactions, we emphasize the importance of periodic monitoring for Bsal within its projected range in the GAR. Our study provides deeper insights into Bsal's ecological niche and the knowledge generated will facilitate conservation efforts in amphibian populations devastated by chytrid pathogens across other regions of the world.
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Affiliation(s)
- Dan Sun
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
| | - Gajaba Ellepola
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
- Department of Zoology, Faculty of Science, University of Peradeniya, Peradeniya, Kandy 20400, Sri Lanka
| | - Jayampathi Herath
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
- School of Biomedical Sciences, International Institute of Health Sciences (IIHS), No. 704 Negombo Road, Welisara 71722, Sri Lanka
| | - Madhava Meegaskumbura
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
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Gray MJ, Carter ED, Piovia-Scott J, Cusaac JPW, Peterson AC, Whetstone RD, Hertz A, Muniz-Torres AY, Bletz MC, Woodhams DC, Romansic JM, Sutton WB, Sheley W, Pessier A, McCusker CD, Wilber MQ, Miller DL. Broad host susceptibility of North American amphibian species to Batrachochytrium salamandrivorans suggests high invasion potential and biodiversity risk. Nat Commun 2023; 14:3270. [PMID: 37277333 DOI: 10.1038/s41467-023-38979-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 05/22/2023] [Indexed: 06/07/2023] Open
Abstract
Batrachochytrium salamandrivorans (Bsal) is a fungal pathogen of amphibians that is emerging in Europe and could be introduced to North America through international trade or other pathways. To evaluate the risk of Bsal invasion to amphibian biodiversity, we performed dose-response experiments on 35 North American species from 10 families, including larvae from five species. We discovered that Bsal caused infection in 74% and mortality in 35% of species tested. Both salamanders and frogs became infected and developed Bsal chytridiomycosis. Based on our host susceptibility results, environmental suitability conditions for Bsal, and geographic ranges of salamanders in the United States, predicted biodiversity loss is expected to be greatest in the Appalachian Region and along the West Coast. Indices of infection and disease susceptibility suggest that North American amphibian species span a spectrum of vulnerability to Bsal chytridiomycosis and most amphibian communities will include an assemblage of resistant, carrier, and amplification species. Predicted salamander losses could exceed 80 species in the United States and 140 species in North America.
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Affiliation(s)
- Matthew J Gray
- Center for Wildlife Health, School of Natural Resources, University of Tennessee, Knoxville, TN, USA.
| | - Edward Davis Carter
- Center for Wildlife Health, School of Natural Resources, University of Tennessee, Knoxville, TN, USA
| | - Jonah Piovia-Scott
- School of Biological Sciences, Washington State University, Vancouver, WA, USA
| | - J Patrick W Cusaac
- Center for Wildlife Health, School of Natural Resources, University of Tennessee, Knoxville, TN, USA
| | - Anna C Peterson
- Center for Wildlife Health, School of Natural Resources, University of Tennessee, Knoxville, TN, USA
| | - Ross D Whetstone
- Biology Department, University of Massachusetts Boston, Boston, MA, USA
| | - Andreas Hertz
- Biology Department, University of Massachusetts Boston, Boston, MA, USA
| | | | - Molly C Bletz
- Biology Department, University of Massachusetts Boston, Boston, MA, USA
| | - Douglas C Woodhams
- Biology Department, University of Massachusetts Boston, Boston, MA, USA
- Smithsonian Tropical Research Institute, Ancón, Panama
| | - John M Romansic
- School of Biological Sciences, Washington State University, Vancouver, WA, USA
| | - William B Sutton
- Department of Agricultural and Environmental Sciences, Tennessee State University, Nashville, TN, USA
| | - Wesley Sheley
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Knoxville, TN, USA
| | - Allan Pessier
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA
| | | | - Mark Q Wilber
- Center for Wildlife Health, School of Natural Resources, University of Tennessee, Knoxville, TN, USA
| | - Debra L Miller
- Center for Wildlife Health, School of Natural Resources, University of Tennessee, Knoxville, TN, USA
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Knoxville, TN, USA
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Schilliger L, Paillusseau C, François C, Bonwitt J. Major Emerging Fungal Diseases of Reptiles and Amphibians. Pathogens 2023; 12:pathogens12030429. [PMID: 36986351 PMCID: PMC10053826 DOI: 10.3390/pathogens12030429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/16/2023] [Accepted: 03/06/2023] [Indexed: 03/11/2023] Open
Abstract
Emerging infectious diseases (EIDs) are caused by pathogens that have undergone recent changes in terms of geographic spread, increasing incidence, or expanding host range. In this narrative review, we describe three important fungal EIDs with keratin trophism that are relevant to reptile and amphibian conservation and veterinary practice. Nannizziopsis spp. have been mainly described in saurians; infection results in thickened, discolored skin crusting, with eventual progression to deep tissues. Previously only reported in captive populations, it was first described in wild animals in Australia in 2020. Ophidiomyces ophidiicola (formely O. ophiodiicola) is only known to infect snakes; clinical signs include ulcerating lesions in the cranial, ventral, and pericloacal regions. It has been associated with mortality events in wild populations in North America. Batrachochytrium spp. cause ulceration, hyperkeratosis, and erythema in amphibians. They are a major cause of catastrophic amphibian declines worldwide. In general, infection and clinical course are determined by host-related characteristics (e.g., nutritional, metabolic, and immune status), pathogens (e.g., virulence and environmental survival), and environment (e.g., temperature, hygrometry, and water quality). The animal trade is thought to be an important cause of worldwide spread, with global modifications in temperature, hygrometry, and water quality further affecting fungal pathogenicity and host immune response.
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Affiliation(s)
- Lionel Schilliger
- Argos Veterinary Clinic of Paris Auteuil, 35 Rue Leconte de Lisle, 75016 Paris, France
- SpéNac Referral Center, 100 Boulevard de la Tour Maubourg, 75007 Paris, France
- Correspondence: ; Tel.: +33-188-616-831
| | - Clément Paillusseau
- Argos Veterinary Clinic of Paris Auteuil, 35 Rue Leconte de Lisle, 75016 Paris, France
- SpéNac Referral Center, 100 Boulevard de la Tour Maubourg, 75007 Paris, France
| | - Camille François
- Argos Veterinary Clinic of Paris Auteuil, 35 Rue Leconte de Lisle, 75016 Paris, France
- SpéNac Referral Center, 100 Boulevard de la Tour Maubourg, 75007 Paris, France
| | - Jesse Bonwitt
- Department of Anthropology, Durham University, South Rd., Durham DH1 3LE, UK
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Plewnia A, Lötters S, Veith M, Peters M, Böning P. Successful Drug-Mediated Host Clearance of Batrachochytrium salamandrivorans. Emerg Infect Dis 2023; 29:411-414. [PMID: 36692470 PMCID: PMC9881767 DOI: 10.3201/eid2902.221162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Skin fungi are among the most dangerous drivers of global amphibian declines, and few mitigation strategies are known. For Batrachochytrium salamandrivorans (Chytridiomycota), available treatments rely on temperature, partially combined with antifungal drugs. We report the clearance of B. salamandrivorans in 2 urodelan species using a solely drug-based approach.
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Crim MJ, Hart ML. Health Monitoring for Laboratory Salamanders. Methods Mol Biol 2023; 2562:41-74. [PMID: 36272067 DOI: 10.1007/978-1-0716-2659-7_3] [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] [Indexed: 06/16/2023]
Abstract
Laboratory animal health monitoring programs are necessary to protect animal health and welfare, the validity of experimental data, and human health against zoonotic infections. Health monitoring programs should be designed based on a risk assessment and knowledge about the biology and transmission of salamander pathogens. Both traditional and molecular diagnostic platforms are available for salamanders, and they provide complementary information. A comprehensive approach to health monitoring leverages the advantages of multiple platforms to provide a more complete picture of colony health and pathogen status. This chapter presents key considerations in the design and implementation of a colony health monitoring program for laboratory salamanders, including protocols for necropsy and sample collection.
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Sheley WC, Gray MJ, Wilber MQ, Cray C, Carter ED, Miller DL. Electrolyte imbalances and dehydration play a key role in Batrachochytrium salamandrivorans chytridiomycosis. Front Vet Sci 2022; 9:1055153. [PMID: 36713878 PMCID: PMC9880075 DOI: 10.3389/fvets.2022.1055153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/28/2022] [Indexed: 01/15/2023] Open
Abstract
Introduction One of the most important emerging infectious diseases of amphibians is caused by the fungal pathogen Batrachochytrium salamandrivorans (Bsal). Bsal was recently discovered and is of global concern due to its potential to cause high mortality in amphibians, especially salamander species. To date, little has been reported on the pathophysiological effects of Bsal; however, studies of a similar fungus, B. dendrobatidis (Bd), have shown that electrolyte losses and immunosuppression likely play a key role in morbidity and mortality associated with this disease. The goal of this study was to investigate pathophysiological effects and immune responses associated with Bsal chytridiomycosis using 49 rough-skinned newts (Taricha granulosa) as the model species. Methods Taricha granulosa were exposed to a 1 × 107 per 10 mL dose of Bsal zoospores and allowed to reach various stages of disease progression before being humanely euthanized. At the time of euthanasia, blood was collected for biochemical and hematological analyses as well as protein electrophoresis. Ten standardized body sections were histologically examined, and Bsal-induced skin lesions were counted and graded on a scale of 1-5 based on severity. Results Results indicated that electrolyte imbalances and dehydration induced by damage to the epidermis likely play a major role in the pathogenesis of Bsal chytridiomycosis in this species. Additionally, Bsal-infected, clinically diseased T. granulosa exhibited a systemic inflammatory response identified through alterations in complete blood counts and protein electrophoretograms. Discussion Overall, these results provide foundational information on the pathogenesis of this disease and highlight the differences and similarities between Bsal and Bd chytridiomycosis.
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Affiliation(s)
- Wesley C. Sheley
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Knoxville, TN, United States
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
- *Correspondence: Wesley C. Sheley
| | - Matthew J. Gray
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
| | - Mark Q. Wilber
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
| | - Carolyn Cray
- Division of Comparative Pathology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - E. Davis Carter
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
| | - Debra L. Miller
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Knoxville, TN, United States
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
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Winter is coming-Temperature affects immune defenses and susceptibility to Batrachochytrium salamandrivorans. PLoS Pathog 2021; 17:e1009234. [PMID: 33600433 PMCID: PMC7891748 DOI: 10.1371/journal.ppat.1009234] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 12/08/2020] [Indexed: 12/24/2022] Open
Abstract
Environmental temperature is a key factor driving various biological processes, including immune defenses and host-pathogen interactions. Here, we evaluated the effects of environmental temperature on the pathogenicity of the emerging fungal pathogen, Batrachochytrium salamandrivorans (Bsal), using controlled laboratory experiments, and measured components of host immune defense to identify regulating mechanisms. We found that adult and juvenile Notophthalmus viridescens died faster due to Bsal chytridiomycosis at 14°C than at 6 and 22°C. Pathogen replication rates, total available proteins on the skin, and microbiome composition likely drove these relationships. Temperature-dependent skin microbiome composition in our laboratory experiments matched seasonal trends in wild N. viridescens, adding validity to these results. We also found that hydrophobic peptide production after two months post-exposure to Bsal was reduced in infected animals compared to controls, perhaps due to peptide release earlier in infection or impaired granular gland function in diseased animals. Using our temperature-dependent susceptibility results, we performed a geographic analysis that revealed N. viridescens populations in the northeastern United States and southeastern Canada are at greatest risk for Bsal invasion, which shifted risk north compared to previous assessments. Our results indicate that environmental temperature will play a key role in the epidemiology of Bsal and provide evidence that temperature manipulations may be a viable disease management strategy. In 2010, a new skin-eating fungus, Batrachochytrium salamandrivorans (Bsal), was discovered killing salamanders in the Netherlands. Since then, the pathogen has spread to other European countries. Bsal is believed to be from Asia and is being translocated through the international trade of amphibians. To our knowledge, Bsal has not arrived to North America. As a proactive strategy for disease control, we evaluated how a range of environmental temperatures in North America could affect invasion risk of Bsal into a widely distributed salamander species, the eastern newt (Notophthalmus viridescens). Our results show that northeastern USA, southeastern Canada, and the higher elevations of the Appalachian Mountains have the greatest likelihood of Bsal invasion, when temperature-dependent susceptibility is included in risk analyses. Changes in eastern newt susceptibility to Bsal infection associated with temperature are likely an interaction between pathogen replication rate and host immune defenses, including changes in skin microbiome composition and the host’s ability to produce Bsal-killing proteins on the skin. Our study provides new insights into how latitude, elevation and season can impact the epidemiology of Bsal, and suggests that strategies that manipulate microclimate of newt habitats could be useful in managing Bsal outbreaks and that climate change will impact Bsal invasion probability.
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Instant killing of pathogenic chytrid fungi by disposable nitrile gloves prevents disease transmission between amphibians. PLoS One 2020; 15:e0241048. [PMID: 33119670 PMCID: PMC7595420 DOI: 10.1371/journal.pone.0241048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 10/07/2020] [Indexed: 12/03/2022] Open
Abstract
To prevent transmission of the pathogenic chytrid fungi Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal), hygiene protocols prescribe the single use of disposable gloves for handling amphibians. We discovered that rinse water from nitrile gloves instantly kills 99% of Bd and Bsal zoospores. Transmission experiments using midwife toads (Alytes obstetricans) and Bd, and Alpine newts (Ichthyosaura alpestris) and Bsal, show that the use of the same pair of gloves for 2 subsequent individuals does not result in significant transmission of any chytrid fungus. In contrast, handling infected amphibians bare-handed caused transmission of Bsal in 4 out of 10 replicates, but did not result in transmission of Bd. Based on the manufacturer’s information, high resolution mass spectrometry (HRMS) and colorimetric tests, calcium lactate and calcium nitrate were identified as compounds with antifungal activity against both Bd and Bsal. These findings corroborate the importance of wearing gloves as an important sanitary measure in amphibian disease prevention. If the highly recommended single use of gloves is not possible, handling multiple post-metamorphic amphibians with the same pair of nitrile gloves should still be preferred above bare-handed manipulation.
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Beukema W, Pasmans F, Van Praet S, Ferri-Yáñez F, Kelly M, Laking AE, Erens J, Speybroeck J, Verheyen K, Lens L, Martel A. Microclimate limits thermal behaviour favourable to disease control in a nocturnal amphibian. Ecol Lett 2020; 24:27-37. [PMID: 33022129 DOI: 10.1111/ele.13616] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/15/2020] [Accepted: 09/07/2020] [Indexed: 11/28/2022]
Abstract
While epizootics increasingly affect wildlife, it remains poorly understood how the environment shapes most host-pathogen systems. Here, we employ a three-step framework to study microclimate influence on ectotherm host thermal behaviour, focusing on amphibian chytridiomycosis in fire salamanders (Salamandra salamandra) infected with the fungal pathogen Batrachochytrium salamandrivorans (Bsal). Laboratory trials reveal that innate variation in thermal preference, rather than behavioural fever, can inhibit infection and facilitate salamander recovery under humidity-saturated conditions. Yet, a 3-year field study and a mesocosm experiment close to the invasive Bsal range show that microclimate constraints suppress host thermal behaviour favourable to disease control. A final mechanistic model, that estimates range-wide, year-round host body temperature relative to microclimate, suggests that these constraints are rule rather than exception. Our results demonstrate how innate host defences against epizootics may remain constrained in the wild, which predisposes to range-wide disease outbreaks and population declines.
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Affiliation(s)
- Wouter Beukema
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Frank Pasmans
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Sarah Van Praet
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Francisco Ferri-Yáñez
- Department of Community Ecology, Helmholtz Centre for Environmental Research (UFZ), Theodor-Lieser-Strasse 4, Halle, 06120, Germany
| | - Moira Kelly
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Alexandra E Laking
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Jesse Erens
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Jeroen Speybroeck
- Research Institute for Nature and Forest - INBO, Havenlaan 88 bus 73, Brussels, 1000, Belgium
| | - Kris Verheyen
- Forest & Nature Lab, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, Gontrode, 9090, Belgium
| | - Luc Lens
- Terrestrial Ecology Unit, Ghent University, K. L, Ledeganckstraat 35, Ghent, 9000, Belgium
| | - An Martel
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
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Li Z, Martel A, Bogaerts S, Göçmen B, Pafilis P, Lymberakis P, Woeltjes T, Veith M, Pasmans F. Landscape Connectivity Limits the Predicted Impact of Fungal Pathogen Invasion. J Fungi (Basel) 2020; 6:E205. [PMID: 33022972 PMCID: PMC7712934 DOI: 10.3390/jof6040205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/29/2020] [Accepted: 09/30/2020] [Indexed: 12/11/2022] Open
Abstract
Infectious diseases are major drivers of biodiversity loss. The risk of fungal diseases to the survival of threatened animals in nature is determined by a complex interplay between host, pathogen and environment. We here predict the risk of invasion of populations of threatened Mediterranean salamanders of the genus Lyciasalamandra by the pathogenic chytrid fungus Batrachochytrium salamandrivorans by combining field sampling and lab trials. In 494 samples across all seven species of Lyciasalamandra, B. salamandrivorans was found to be absent. Single exposure to a low (1000) number of fungal zoospores resulted in fast buildup of lethal infections in three L. helverseni. Thermal preference of the salamanders was well within the thermal envelope of the pathogen and body temperatures never exceeded the fungus' thermal critical maximum, limiting the salamanders' defense opportunities. The relatively low thermal host preference largely invalidates macroclimatic based habitat suitability predictions and, combined with current pathogen absence and high host densities, suggests a high probability of local salamander population declines upon invasion by B. salamandrivorans. However, the unfavorable landscape that shaped intraspecific host genetic diversity, lack of known alternative hosts and rapid host mortality after infection present barriers to further, natural pathogen dispersal between populations and thus species extinction. The risk of anthropogenic spread stresses the importance of biosecurity in amphibian habitats.
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Affiliation(s)
- Zhimin Li
- Wildlife Health Ghent, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B9820 Merelbeke, Belgium; (Z.L.); (A.M.)
| | - An Martel
- Wildlife Health Ghent, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B9820 Merelbeke, Belgium; (Z.L.); (A.M.)
| | | | - Bayram Göçmen
- Faculty of Science, Department of Biology, Zoology Section, Ege University, TR-35100 İzmir, Turkey
| | - Panayiotis Pafilis
- Department of Zoology and Marine Biology, School of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, Ilissia, 15784 Athens, Greece;
| | - Petros Lymberakis
- Natural History Museum of Crete, School of Sciences and Engineering, University of Crete, Knossos Ave., 1409 Irakleio, Greece;
| | | | - Michael Veith
- Department of Biogeography, Trier University, Universitätsring 15, D-54296 Trier, Germany;
| | - Frank Pasmans
- Wildlife Health Ghent, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B9820 Merelbeke, Belgium; (Z.L.); (A.M.)
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Rollins-Smith LA. Global Amphibian Declines, Disease, and the Ongoing Battle between Batrachochytrium Fungi and the Immune System. HERPETOLOGICA 2020. [DOI: 10.1655/0018-0831-76.2.178] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Louise A. Rollins-Smith
- Departments of Pathology, Microbiology and Immunology and Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA
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Martel A, Vila‐Escale M, Fernández‐Giberteau D, Martinez‐Silvestre A, Canessa S, Van Praet S, Pannon P, Chiers K, Ferran A, Kelly M, Picart M, Piulats D, Li Z, Pagone V, Pérez‐Sorribes L, Molina C, Tarragó‐Guarro A, Velarde‐Nieto R, Carbonell F, Obon E, Martínez‐Martínez D, Guinart D, Casanovas R, Carranza S, Pasmans F. Integral chain management of wildlife diseases. Conserv Lett 2020. [DOI: 10.1111/conl.12707] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Affiliation(s)
- An Martel
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Mireia Vila‐Escale
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Daniel Fernández‐Giberteau
- Grup de Recerca de l'Escola de la Natura de Parets del Vallès – Ajuntament de Parets del Vallès Parets del Vallès Spain
| | | | - Stefano Canessa
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Sarah Van Praet
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Pep Pannon
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Koen Chiers
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Albert Ferran
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Moira Kelly
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Mariona Picart
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Dolors Piulats
- Institute of Evolutionary Biology (CSIC‐UPF) Barcelona Spain
| | - Zhimin Li
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Viviana Pagone
- Institute of Evolutionary Biology (CSIC‐UPF) Barcelona Spain
| | - Laia Pérez‐Sorribes
- Grup de Recerca de l'Escola de la Natura de Parets del Vallès – Ajuntament de Parets del Vallès Parets del Vallès Spain
| | - Carolina Molina
- Grup de Recerca de l'Escola de la Natura de Parets del Vallès – Ajuntament de Parets del Vallès Parets del Vallès Spain
| | - Aïda Tarragó‐Guarro
- Departament de Territori i SostenibilitatGeneralitat de Catalunya Barcelona Spain
| | - Roser Velarde‐Nieto
- Departament de Medicina i Cirurgia AnimalsFacultat de VeterinàriaUniversitat Autònoma de Barcelona Bellaterra Spain
| | - Francesc Carbonell
- Àrea de Gestió Ambiental Servei de Fauna i Flora (Centre de Fauna de Torreferrussa) Santa Perpètua de Mogoda Spain
| | - Elena Obon
- Àrea de Gestió Ambiental Servei de Fauna i Flora (Centre de Fauna de Torreferrussa) Santa Perpètua de Mogoda Spain
| | | | - Daniel Guinart
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Ricard Casanovas
- Departament de Territori i SostenibilitatGeneralitat de Catalunya Barcelona Spain
| | | | - Frank Pasmans
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
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13
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Ellison A, Zamudio K, Lips K, Muletz‐Wolz C. Temperature‐mediated shifts in salamander transcriptomic responses to the amphibian‐killing fungus. Mol Ecol 2020; 29:325-343. [DOI: 10.1111/mec.15327] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/04/2019] [Accepted: 12/03/2019] [Indexed: 12/14/2022]
Affiliation(s)
- Amy Ellison
- School of Natural Sciences Bangor University Bangor UK
| | - Kelly Zamudio
- Department of Ecology & Evolutionary Biology Cornell University Ithaca NY USA
| | - Karen Lips
- Department of Biology University of Maryland College Park MD USA
| | - Carly Muletz‐Wolz
- Department of Biology University of Maryland College Park MD USA
- Center for Conservation Genomics Smithsonian Conservation Biology Institute National Zoological Park Washington DC USA
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14
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Canessa S, Spitzen‐van der Sluijs A, Stark T, Allen BE, Bishop PJ, Bletz M, Briggs CJ, Daversa DR, Gray MJ, Griffiths RA, Harris RN, Harrison XA, Hoverman JT, Jervis P, Muths E, Olson DH, Price SJ, Richards‐Zawacki CL, Robert J, Rosa GM, Scheele BC, Schmidt BR, Garner TWJ. Conservation decisions under pressure: Lessons from an exercise in rapid response to wildlife disease. CONSERVATION SCIENCE AND PRACTICE 2019. [DOI: 10.1111/csp2.141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Affiliation(s)
- Stefano Canessa
- Wildlife Health Ghent, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | | | - Tariq Stark
- Reptile, Amphibian & Fish Conservation Netherlands (RAVON) Nijmegen The Netherlands
| | - Bryony E. Allen
- Institute of ZoologyZoological Society of London, Regents Park London UK
- Institute for Integrative BiologyUniversity of Liverpool Liverpool UK
| | - Phillip J. Bishop
- Department of ZoologyUniversity of Otago Dunedin New Zealand
- Amphibian Survival Alliance London UK
| | - Molly Bletz
- Biology DepartmentUniversity of Massachusetts Boston Massachusetts
| | - Cheryl J. Briggs
- Department of Ecology, Evolution and Marine BiologyUniversity of California Santa Barbara California
| | - David R. Daversa
- Institute of ZoologyZoological Society of London, Regents Park London UK
- Institute for Integrative BiologyUniversity of Liverpool Liverpool UK
| | - Matthew J. Gray
- Center for Wildlife HealthUniversity of Tennessee Institute of Agriculture Knoxville Tennessee
| | - Richard A. Griffiths
- Durrell Institute of Conservation and Ecology, School of Anthropology and ConservationUniversity of Kent Kent UK
| | - Reid N. Harris
- Amphibian Survival Alliance London UK
- Department of BiologyJames Madison University Harrisonburg Virginia
| | | | - Jason T. Hoverman
- Department of Forestry and Natural ResourcesPurdue University West Lafayette Indiana
| | - Phillip Jervis
- Institute of ZoologyZoological Society of London, Regents Park London UK
- Faculty of Medicine, School of Public HealthImperial College London UK
| | - Erin Muths
- United States Geological Survey Fort Collins Colorado
| | - Deanna H. Olson
- Pacific Northwest Research Station, US Forest Service Corvallis Oregon
| | | | | | - Jacques Robert
- Department of Microbiology & ImmunologyUniversity of Rochester Rochester New York
| | - Gonçalo M. Rosa
- Institute of ZoologyZoological Society of London, Regents Park London UK
- Centre for Ecology, Evolution and Environmental Changes (CE3C), Faculdade de Ciências da Universidade de Lisboa Lisbon Portugal
| | - Ben C. Scheele
- Fenner School of Environment and SocietyThe Australian National University Canberra Australian Capital Territory Australia
| | - Benedikt R. Schmidt
- Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich Zürich Switzerland
- Info Fauna Karch Neuchâtel Switzerland
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15
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Ambient temperature alters body size and gut microbiota of Xenopus tropicalis. SCIENCE CHINA-LIFE SCIENCES 2019; 63:915-925. [PMID: 31686318 DOI: 10.1007/s11427-019-9540-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/09/2019] [Indexed: 02/07/2023]
Abstract
Temperature is important to determine physiological status of ectotherms. However, it is still not fully understood how amphibians and their symbiotic microbiota acclimate to ambient temperature. In this study, we investigated the changes of gut microbiota of Xenopus tropicalis at different temperatures under controlled laboratory conditions. The results showed that microbial communities were distinct and shared only a small overlap among froglet guts, culture water and food samples. Furthermore, the dominant taxa harbored in the gut exhibited low relative abundance in water and food. It indicates that bacterial taxa selected by amphibian gut were generally of low abundance in the external environment. Temperature could affect beta-diversity of gut microbiota in terms of phylogenetic distance, but it did not affect alpha diversity. The composition of gut microbiota was similar in warm and cool treatments. However, signature taxa in different temperature environments were identified. The relationships between temperature, gut microbiota and morphology traits of X. tropicalis revealed in this study help us to predict the consequences of environmental changes on ectothermic animals.
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16
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Ossiboff RJ, Towe AE, Brown MA, Longo AV, Lips KR, Miller DL, Carter ED, Gray MJ, Frasca S. Differentiating Batrachochytrium dendrobatidis and B. salamandrivorans in Amphibian Chytridiomycosis Using RNAScope ® in situ Hybridization. Front Vet Sci 2019; 6:304. [PMID: 31572738 PMCID: PMC6751264 DOI: 10.3389/fvets.2019.00304] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 08/28/2019] [Indexed: 12/25/2022] Open
Abstract
Batrachochytrium dendrobatidis and B. salamandrivorans are important amphibian pathogens responsible for morbidity and mortality in free-ranging and captive frogs, salamanders, and caecilians. While B. dendrobatidis has a widespread global distribution, B. salamandrivorans has only been detected in amphibians in Asia and Europe. Although molecular detection methods for these fungi are well-characterized, differentiation of the morphologically similar organisms in the tissues of affected amphibians is incredibly difficult. Moreover, an accurate tool to identify and differentiate Batrachochytrium in affected amphibian tissues is essential for a specific diagnosis of the causative agent in chytridiomycosis cases. To address this need, an automated dual-plex chromogenic RNAScope®in situ hybridization (ISH) assay was developed and characterized for simultaneous detection and differentiation of B. dendrobatidis and B. salamandrivorans. The assay, utilizing double Z target probe pairs designed to hybridize to 28S rRNA sequences, was specific for the identification of both organisms in culture and in formalin-fixed paraffin-embedded amphibian tissues. The assay successfully identified organisms in tissue samples from five salamander and one frog species preserved in formalin for up to 364 days and was sensitive for the detection of Batrachochytrium in animals with qPCR loads as low as 1.1 × 102 zoospores/microliter. ISH staining of B. salamandrivorans also highlighted the infection of dermal cutaneous glands, a feature not observed in amphibian B. dendrobatidis cases and which may play an important role in B. salamandrivorans pathogenesis in salamanders. The developed ISH assay will benefit both amphibian chytridiomycosis surveillance projects and pathogenesis studies by providing a reliable tool for Batrachochytrium differentiation in tissues.
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Affiliation(s)
- Robert J Ossiboff
- Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States
| | - Anastasia E Towe
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Melissa A Brown
- Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States
| | - Ana V Longo
- Department of Biology, University of Florida, Gainesville, FL, United States.,Department of Biology, University of Maryland College Park, College Park, MD, United States
| | - Karen R Lips
- Department of Biology, University of Maryland College Park, College Park, MD, United States
| | - Debra L Miller
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Knoxville, TN, United States.,Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
| | - E Davis Carter
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
| | - Matthew J Gray
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
| | - Salvatore Frasca
- Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States
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17
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Bates KA, Shelton JMG, Mercier VL, Hopkins KP, Harrison XA, Petrovan SO, Fisher MC. Captivity and Infection by the Fungal Pathogen Batrachochytrium salamandrivorans Perturb the Amphibian Skin Microbiome. Front Microbiol 2019; 10:1834. [PMID: 31507541 PMCID: PMC6716147 DOI: 10.3389/fmicb.2019.01834] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/25/2019] [Indexed: 12/13/2022] Open
Abstract
The emerging fungal pathogen, Batrachochytrium salamandrivorans (Bsal) is responsible for the catastrophic decline of European salamanders and poses a threat to amphibians globally. The amphibian skin microbiome can influence disease outcome for several host-pathogen systems, yet little is known of its role in Bsal infection. In addition, many experimental in-vivo amphibian disease studies to date have relied on specimens that have been kept in captivity for long periods without considering the influence of environment on the microbiome and how this may impact the host response to pathogen exposure. We characterized the impact of captivity and exposure to Bsal on the skin bacterial and fungal communities of two co-occurring European newt species, the smooth newt, Lissotriton vulgaris and the great-crested newt, Triturus cristatus. We show that captivity led to significant losses in bacterial and fungal diversity of amphibian skin, which may be indicative of a decline in microbe-mediated protection. We further demonstrate that in both L. vulgaris and T. cristatus, Bsal infection was associated with changes in the composition of skin bacterial communities with possible negative consequences to host health. Our findings advance current understanding of the role of host-associated microbiota in Bsal infection and highlight important considerations for ex-situ amphibian conservation programmes.
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Affiliation(s)
- Kieran A Bates
- Department of Zoology, University of Oxford, Oxford, United Kingdom.,Department of Infectious Disease Epidemiology, MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom.,Institute of Zoology, Zoological Society of London, London, United Kingdom
| | - Jennifer M G Shelton
- Department of Infectious Disease Epidemiology, MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
| | - Victoria L Mercier
- Department of Infectious Disease Epidemiology, MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
| | - Kevin P Hopkins
- Institute of Zoology, Zoological Society of London, London, United Kingdom
| | - Xavier A Harrison
- Institute of Zoology, Zoological Society of London, London, United Kingdom.,College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Silviu O Petrovan
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom.,Froglife, Peterborough, United Kingdom
| | - Matthew C Fisher
- Department of Infectious Disease Epidemiology, MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
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18
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Hettyey A, Ujszegi J, Herczeg D, Holly D, Vörös J, Schmidt BR, Bosch J. Mitigating Disease Impacts in Amphibian Populations: Capitalizing on the Thermal Optimum Mismatch Between a Pathogen and Its Host. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00254] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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19
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Muletz-Wolz CR, Fleischer RC, Lips KR. Fungal disease and temperature alter skin microbiome structure in an experimental salamander system. Mol Ecol 2019; 28:2917-2931. [PMID: 31066947 DOI: 10.1111/mec.15122] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 03/27/2019] [Accepted: 04/25/2019] [Indexed: 12/29/2022]
Abstract
Pathogens compete with host microbiomes for space and resources. Their shared environment impacts pathogen-microbiome-host interactions, which can lead to variation in disease outcome. The skin microbiome of red-backed salamanders (Plethodon cinereus) can reduce infection by the pathogen Batrachochytrium dendrobatidis (Bd) at moderate infection loads, with high species richness and high abundance of competitors as putative mechanisms. However, it is unclear if the skin microbiome can reduce epizootic Bd loads across temperatures. We conducted a laboratory experiment to quantify skin microbiome and host responses (P. cinereus: n = 87) to Bd at mimicked epizootic loads across temperatures (13, 17 and 21°C). We quantified skin microbiomes using 16S rRNA gene metabarcoding and identified operational taxonomic units (OTUs) taxonomically similar to culturable bacteria known to kill Bd (anti-Bd OTUs). Prior to pathogen exposure, temperature changed the microbiome (OTU richness decreased by 12% and the abundance of anti-Bd OTUs increased by 18% per degree increase in temperature), but these changes were not predictive of disease outcome. After exposure, Bd changed the microbiome (OTU richness decreased by 0.1% and the abundance of anti-Bd OTUs increased by 0.2% per 1% increase in Bd load) and caused high host mortality across temperatures (35/45: 78%). Temperature indirectly impacted microbiome change and mortality through its direct effect on pathogen load. We did not find support for the microbiome impacting Bd load or host survival. Our research reveals complex host, pathogen, microbiome and environmental interactions to demonstrate that during epizootic events the microbiome will be unlikely to reduce pathogen invasion, even for putatively Bd-resistant species.
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Affiliation(s)
- Carly R Muletz-Wolz
- Department of Biology, University of Maryland, College Park, Maryland.,Center for Conservation Genomics, Smithsonian National Zoological Park and Conservation Biology Institute, Washington, District of Columbia
| | - Robert C Fleischer
- Center for Conservation Genomics, Smithsonian National Zoological Park and Conservation Biology Institute, Washington, District of Columbia
| | - Karen R Lips
- Department of Biology, University of Maryland, College Park, Maryland
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20
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Sabino-Pinto J, Krause ET, Bletz MC, Martel A, Pasmans F, Steinfartz S, Vences M. Detectability vs. time and costs in pooled DNA extraction of cutaneous swabs: a study on the amphibian chytrid fungi. AMPHIBIA-REPTILIA 2019. [DOI: 10.1163/15685381-20181011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Epidemiology relies on understanding the distribution of pathogens which often can be detected through DNA-based techniques, such as quantitative Polymerase Chain Reaction (qPCR). Typically, the DNA of each individual sample is separately extracted and undergoes qPCR analysis. However, when performing field surveys and long-term monitoring, a large fraction of the samples is generally expected to be negative, especially in geographical areas still considered free of the pathogen. If pathogen detection within a population – rather than determining its individual prevalence – is the focus, work load and monetary costs can be reduced by pooling samples for DNA extraction. We test and refine a user-friendly technique where skin swabs can be pooled during DNA extraction to detect the amphibian chytrid fungi, Batrachochytrium dendrobatidis and B. salamandrivorans (Bsal). We extracted pools with different numbers of samples (from one to four swabs), without increasing reaction volumes, and each pool had one sample inoculated with a predetermined zoospore amount. Pool size did not reduce the ability to detect the two fungi, except if inoculated with extremely low zoospore amounts (one zoospore). We confirm that pooled DNA extraction of cutaneous swabs can substantially reduce processing time and costs without minimizing detection sensitivity. This is of relevance especially for the new emerging pathogen Bsal, for which pooled DNA extraction had so far not been tested and massive monitoring efforts in putatively unaffected regions are underway.
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Affiliation(s)
- Joana Sabino-Pinto
- 1Zoological Institute, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - E. Tobias Krause
- 2Friedrich-Loeffler-Institute, Institute of Animal Welfare and Animal Husbandry, 29223 Celle, Germany
| | - Molly C. Bletz
- 1Zoological Institute, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - An Martel
- 3Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - Frank Pasmans
- 3Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - Sebastian Steinfartz
- 1Zoological Institute, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Miguel Vences
- 1Zoological Institute, Braunschweig University of Technology, 38106 Braunschweig, Germany
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21
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Fitzpatrick LD, Pasmans F, Martel A, Cunningham AA. Epidemiological tracing of Batrachochytrium salamandrivorans identifies widespread infection and associated mortalities in private amphibian collections. Sci Rep 2018; 8:13845. [PMID: 30218076 PMCID: PMC6138723 DOI: 10.1038/s41598-018-31800-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 08/23/2018] [Indexed: 12/17/2022] Open
Abstract
The amphibian chytrid fungus Batrachochytrium salamandrivorans (Bsal) infects newts and salamanders (urodele amphibians), in which it can cause fatal disease. This pathogen has caused dramatic fire salamander population declines in Belgium, the Netherlands and Germany since its discovery in 2010. Thought to be native to Asia, it has been hypothesised that Bsal was introduced to Europe with the importation of infected amphibians for the commercial pet trade. Following the discovery of Bsal in captive amphibians in the United Kingdom in 2015, we used contact-tracing to identify epidemiologically-linked private amphibian collections in Western Europe. Of 16 linked collections identified, animals were tested from 11 and urodeles tested positive for Bsal in seven, including the identification of the pathogen in Spain for the first time. Mortality of Bsal-positive individuals was observed in five collections. Our results indicate that Bsal is likely widespread within the private amphibian trade, at least in Europe. These findings are important for informing policy regarding Bsal control strategies.
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Affiliation(s)
- Liam D Fitzpatrick
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, UK
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Andrew A Cunningham
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, UK.
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22
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Asymptomatic infection of the fungal pathogen Batrachochytrium salamandrivorans in captivity. Sci Rep 2018; 8:11767. [PMID: 30082745 PMCID: PMC6078946 DOI: 10.1038/s41598-018-30240-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 07/14/2018] [Indexed: 12/30/2022] Open
Abstract
One of the most important factors driving amphibian declines worldwide is the infectious disease, chytridiomycosis. Two fungi have been associated with this disease, Batrachochytrium dendrobatidis and B. salamandrivorans (Bsal). The latter has recently driven Salamandra salamandra populations to extirpation in parts of the Netherlands, and Belgium, and potentially also in Germany. Bsal has been detected in the pet trade, which has been hypothesized to be the pathway by which it reached Europe, and which may continuously contribute to its spread. In the present study, 918 amphibians belonging to 20 captive collections in Germany and Sweden were sampled to explore the extent of Bsal presence in captivity. The fungus was detected by quantitative Polymerase Chain Reaction (qPCR) in ten collections, nine of which lacked clinical symptoms. 23 positives were confirmed by independent processing of duplicate swabs, which were analysed in a separate laboratory, and/or by sequencing ITS and 28 S gene segments. These asymptomatic positives highlight the possibility of Bsal being widespread in captive collections, and is of high conservation concern. This finding may increase the likelihood of the pathogen being introduced from captivity into the wild, and calls for according biosecurity measures. The detection of Bsal-positive alive specimens of the hyper-susceptible fire salamander could indicate the existence of a less aggressive Bsal variant or the importance of environmental conditions for infection progression.
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23
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Moretti EH, Ortega Chinchilla JE, Marques FS, Fernandes PAC, Gomes FR. Behavioral fever decreases metabolic response to lipopolysaccharide in yellow Cururu toads (Rhinella icterica). Physiol Behav 2018; 191:73-81. [DOI: 10.1016/j.physbeh.2018.04.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 04/05/2018] [Accepted: 04/05/2018] [Indexed: 10/17/2022]
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24
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Fisher MC, Ghosh P, Shelton JMG, Bates K, Brookes L, Wierzbicki C, Rosa GM, Farrer RA, Aanensen DM, Alvarado-Rybak M, Bataille A, Berger L, Böll S, Bosch J, Clare FC, A Courtois E, Crottini A, Cunningham AA, Doherty-Bone TM, Gebresenbet F, Gower DJ, Höglund J, James TY, Jenkinson TS, Kosch TA, Lambertini C, Laurila A, Lin CF, Loyau A, Martel A, Meurling S, Miaud C, Minting P, Ndriantsoa S, O'Hanlon SJ, Pasmans F, Rakotonanahary T, Rabemananjara FCE, Ribeiro LP, Schmeller DS, Schmidt BR, Skerratt L, Smith F, Soto-Azat C, Tessa G, Toledo LF, Valenzuela-Sánchez A, Verster R, Vörös J, Waldman B, Webb RJ, Weldon C, Wombwell E, Zamudio KR, Longcore JE, Garner TWJ. Development and worldwide use of non-lethal, and minimal population-level impact, protocols for the isolation of amphibian chytrid fungi. Sci Rep 2018; 8:7772. [PMID: 29773857 PMCID: PMC5958081 DOI: 10.1038/s41598-018-24472-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 03/23/2018] [Indexed: 11/09/2022] Open
Abstract
Parasitic chytrid fungi have emerged as a significant threat to amphibian species worldwide, necessitating the development of techniques to isolate these pathogens into culture for research purposes. However, early methods of isolating chytrids from their hosts relied on killing amphibians. We modified a pre-existing protocol for isolating chytrids from infected animals to use toe clips and biopsies from toe webbing rather than euthanizing hosts, and distributed the protocol to researchers as part of the BiodivERsA project RACE; here called the RML protocol. In tandem, we developed a lethal procedure for isolating chytrids from tadpole mouthparts. Reviewing a database of use a decade after their inception, we find that these methods have been applied across 5 continents, 23 countries and in 62 amphibian species. Isolation of chytrids by the non-lethal RML protocol occured in 18% of attempts with 207 fungal isolates and three species of chytrid being recovered. Isolation of chytrids from tadpoles occured in 43% of attempts with 334 fungal isolates of one species (Batrachochytrium dendrobatidis) being recovered. Together, these methods have resulted in a significant reduction and refinement of our use of threatened amphibian species and have improved our ability to work with this group of emerging pathogens.
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Affiliation(s)
- Matthew C Fisher
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK.
| | - Pria Ghosh
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK.,Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom, 2520, South Africa
| | - Jennifer M G Shelton
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK
| | - Kieran Bates
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK
| | - Lola Brookes
- Institute of Zoology, Regent's Park, London, NW1 4RY, UK
| | - Claudia Wierzbicki
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK
| | - Gonçalo M Rosa
- Institute of Zoology, Regent's Park, London, NW1 4RY, UK.,Centre for Ecology, Evolution and Environmental Changes (CE3C), Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal
| | - Rhys A Farrer
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK
| | - David M Aanensen
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK.,Centre for Genomic Pathogen Surveillance, Wellcome Genome Campus, Cambridgeshire, UK
| | - Mario Alvarado-Rybak
- Centro de Investigación para la Sustentabilidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Republica 440, Santiago, Chile
| | - Arnaud Bataille
- Laboratory of Behavioral and Population Ecology, School of Biological Sciences, Seoul National University, Seoul, 08826, South Korea.,CIRAD, UMR ASTRE, F-34398 Montpellier, France; ASTRE, Univ Montpellier, CIRAD, INRA, Montpellier, France
| | - Lee Berger
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, 4811, Australia
| | - Susanne Böll
- Agency for Population Ecology and Nature Conservancy, Gerbrunn, Germany
| | - Jaime Bosch
- Museo Nacional de Ciencias Naturales, CSIC c/Jose Gutierrez Abascal 2, 28006, Madrid, Spain
| | - Frances C Clare
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK
| | - Elodie A Courtois
- Laboratoire Ecologie, évolution, interactions des systèmes amazoniens (LEEISA), Université de Guyane, CNRS, IFREMER, 97300, Cayenne, French Guiana
| | - Angelica Crottini
- CIBIO - Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO, Universidade do Porto, 4485-661, Vairão, Portugal
| | | | | | - Fikirte Gebresenbet
- Department of Integrative Biology, Oklahoma State University, 113 Life Sciences West, Stillwater, OK, 74078, USA
| | - David J Gower
- Life Sciences, The Natural History Museum, London, SW7 5BD, UK
| | - Jacob Höglund
- Department of Ecology and Genetics, EBC, Uppsala University, Norbyv. 18D, SE-75236, Uppsala, Sweden
| | - Timothy Y James
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Thomas S Jenkinson
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Tiffany A Kosch
- Laboratory of Behavioral and Population Ecology, School of Biological Sciences, Seoul National University, Seoul, 08826, South Korea.,One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, 4811, Australia
| | - Carolina Lambertini
- Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, 13083-862, Brazil
| | - Anssi Laurila
- Department of Ecology and Genetics, EBC, Uppsala University, Norbyv. 18D, SE-75236, Uppsala, Sweden
| | - Chun-Fu Lin
- Zoology Division, Endemic Species Research Institute, 1 Ming-shen East Road, Jiji, Nantou, 552, Taiwan
| | - Adeline Loyau
- Helmholtz Centre for Environmental Research - UFZ, Department of Conservation Biology, Permoserstrasse 15, 04318, Leipzig, Germany.,ECOLAB, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium
| | - Sara Meurling
- Department of Ecology and Genetics, EBC, Uppsala University, Norbyv. 18D, SE-75236, Uppsala, Sweden
| | - Claude Miaud
- PSL Research University, CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, Biogéographie et Ecologie des vertébrés, Montpellier, France
| | - Pete Minting
- Amphibian and Reptile Conservation (ARC) Trust, 655A Christchurch Road, Boscombe, Bournemouth, Dorset, BH1 4AP, UK
| | - Serge Ndriantsoa
- Durrell Wildlife Conservation Trust, Madagascar Programme, Antananarivo, Madagascar
| | - Simon J O'Hanlon
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, W2 1PG, UK.,Institute of Zoology, Regent's Park, London, NW1 4RY, UK
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium
| | | | - Falitiana C E Rabemananjara
- Durrell Wildlife Conservation Trust, Madagascar Programme, Antananarivo, Madagascar.,IUCN SSC Amphibian Specialist Group-Madagascar, 101, Antananarivo, Madagascar
| | - Luisa P Ribeiro
- Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, 13083-862, Brazil
| | - Dirk S Schmeller
- Helmholtz Centre for Environmental Research - UFZ, Department of Conservation Biology, Permoserstrasse 15, 04318, Leipzig, Germany.,ECOLAB, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Benedikt R Schmidt
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.,Info Fauna Karch, Université de Neuchâtel, Bellevaux 51, UniMail Bâtiment 6, 2000, Neuchâtel, Switzerland
| | - Lee Skerratt
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, 4811, Australia
| | - Freya Smith
- National Wildlife Management Centre, APHA, Woodchester Park, Gloucestershire, GL10 3UJ, UK
| | - Claudio Soto-Azat
- Centro de Investigación para la Sustentabilidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Republica 440, Santiago, Chile
| | - Giulia Tessa
- Non-profit Association Zirichiltaggi - Sardinia Wildlife Conservation, Strada Vicinale Filigheddu 62/C, I-07100, Sassari, Italy
| | - Luís Felipe Toledo
- Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, 13083-862, Brazil
| | - Andrés Valenzuela-Sánchez
- Centro de Investigación para la Sustentabilidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Republica 440, Santiago, Chile.,ONG Ranita de Darwin, Nataniel Cox 152, Santiago, Chile
| | - Ruhan Verster
- Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom, 2520, South Africa
| | - Judit Vörös
- Collection of Amphibians and Reptiles, Department of Zoology, Hungarian Natural History Museum, Budapest, Baross u, 13., 1088, Hungary
| | - Bruce Waldman
- Laboratory of Behavioral and Population Ecology, School of Biological Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Rebecca J Webb
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, 4811, Australia
| | - Che Weldon
- Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom, 2520, South Africa
| | - Emma Wombwell
- Institute of Zoology, Regent's Park, London, NW1 4RY, UK
| | - Kelly R Zamudio
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, 14853, USA
| | - Joyce E Longcore
- School of Biology and Ecology, University of Maine, Orono, Maine, 04469, USA
| | - Trenton W J Garner
- Institute of Zoology, Regent's Park, London, NW1 4RY, UK.,Non-profit Association Zirichiltaggi - Sardinia Wildlife Conservation, Strada Vicinale Filigheddu 62/C, I-07100, Sassari, Italy.,Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom, 2520, South Africa
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25
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More S, Angel Miranda M, Bicout D, Bøtner A, Butterworth A, Calistri P, Depner K, Edwards S, Garin-Bastuji B, Good M, Michel V, Raj M, Saxmose Nielsen S, Sihvonen L, Spoolder H, Stegeman JA, Thulke HH, Velarde A, Willeberg P, Winckler C, Baláž V, Martel A, Murray K, Fabris C, Munoz-Gajardo I, Gogin A, Verdonck F, Gortázar Schmidt C. Risk of survival, establishment and spread of Batrachochytrium salamandrivorans (Bsal) in the EU. EFSA J 2018; 16:e05259. [PMID: 32625888 PMCID: PMC7009437 DOI: 10.2903/j.efsa.2018.5259] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Batrachochytrium salamandrivorans (Bsal) is an emerging fungal pathogen of salamanders. Despite limited surveillance, Bsal was detected in kept salamanders populations in Belgium, Germany, Spain, the Netherlands and the United Kingdom, and in wild populations in some regions of Belgium, Germany and the Netherlands. According to niche modelling, at least part of the distribution range of every salamander species in Europe overlaps with the climate conditions predicted to be suitable for Bsal. Passive surveillance is considered the most suitable approach for detection of Bsal emergence in wild populations. Demonstration of Bsal absence is considered feasible only in closed populations of kept susceptible species. In the wild, Bsal can spread by both active (e.g. salamanders, anurans) and passive (e.g. birds, water) carriers; it is most likely maintained/spread in infected areas by contacts of salamanders or by interactions with anurans, whereas human activities most likely cause Bsal entry into new areas and populations. In kept amphibians, Bsal contamination via live silent carriers (wild birds and anurans) is considered extremely unlikely. The risk‐mitigation measures that were considered the most feasible and effective: (i) for ensuring safer international or intra‐EU trade of live salamanders, are: ban or restrictions on salamander imports, hygiene procedures and good practice manuals; (ii) for protecting kept salamanders from Bsal, are: identification and treatment of positive collections; (iii) for on‐site protection of wild salamanders, are: preventing translocation of wild amphibians and release/return to the wild of kept/temporarily housed wild salamanders, and setting up contact points/emergency teams for passive surveillance. Combining several risk‐mitigation measures improve the overall effectiveness. It is recommended to: introduce a harmonised protocol for Bsal detection throughout the EU; improve data acquisition on salamander abundance and distribution; enhance passive surveillance activities; increase public and professionals’ awareness; condition any movement of captive salamanders on Bsal known health status.
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26
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Yuan Z, Martel A, Wu J, Van Praet S, Canessa S, Pasmans F. Widespread occurrence of an emerging fungal pathogen in heavily traded Chinese urodelan species. Conserv Lett 2018. [DOI: 10.1111/conl.12436] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Zhiyong Yuan
- Key Laboratory for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Ministry of Education; Southwest Forestry University; Yunnan 650224 China
- Key Laboratory of Forest Disaster Warning and Control of Yunnan Province; Southwest Forestry University; Kunming Yunnan 650224 China
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine; Ghent University; Salisburylaan 133 Merelbeke 9820 Belgium
| | - Jun Wu
- Nanjing Institute of Environmental Sciences; Ministry of Environmental Protection of China; Nanjing Jiangsu 210042 China
| | - Sarah Van Praet
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine; Ghent University; Salisburylaan 133 Merelbeke 9820 Belgium
| | - Stefano Canessa
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine; Ghent University; Salisburylaan 133 Merelbeke 9820 Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine; Ghent University; Salisburylaan 133 Merelbeke 9820 Belgium
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27
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Thomas V, Blooi M, Van Rooij P, Van Praet S, Verbrugghe E, Grasselli E, Lukac M, Smith S, Pasmans F, Martel A. Recommendations on diagnostic tools for Batrachochytrium salamandrivorans. Transbound Emerg Dis 2018; 65:e478-e488. [PMID: 29341499 DOI: 10.1111/tbed.12787] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Indexed: 02/05/2023]
Abstract
Batrachochytrium salamandrivorans (Bsal) poses a major threat to amphibian, and more specifically caudata, diversity. Bsal is currently spreading through Europe, and mitigation measures aimed at stopping its spread and preventing its introduction into naïve environments are urgently needed. Screening for presence of Bsal and diagnosis of Bsal-induced disease in amphibians are essential core components of effective mitigation plans. Therefore, the aim of this study was to present an overview of all Bsal diagnostic tools together with their limitations and to suggest guidelines to allow uniform interpretation. Here, we investigate the use of different diagnostic tools in post-mortem detection of Bsal and whether competition between Bd and Bsal occurs in the species-specific Bd and Bsal duplex real-time PCR. We also investigate the diagnostic sensitivity, diagnostic specificity and reproducibility of the Bsal real-time PCR and show the use of immunohistochemistry in diagnosis of Bsal-induced chytridiomycosis in amphibian samples stored in formaldehyde. Additionally, we have drawn up guidelines for the use and interpretation of the different diagnostic tools for Bsal currently available, to facilitate standardization of execution and interpretation.
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Affiliation(s)
- V Thomas
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - M Blooi
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - P Van Rooij
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - S Van Praet
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - E Verbrugghe
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - E Grasselli
- Dipartimento di Scienze della Terra, dell'Ambiente e della Vita, DISTAV, Universita di Genova, Genova, Italy
| | - M Lukac
- Department of Poultry Diseases with Clinic, Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - S Smith
- Department of Integrative Biology and Evolution, University of Veterinary Medicine, Vienna, Austria
| | - F Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - A Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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28
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Yap TA, Nguyen NT, Serr M, Shepack A, Vredenburg VT. Batrachochytrium salamandrivorans and the Risk of a Second Amphibian Pandemic. ECOHEALTH 2017; 14:851-864. [PMID: 29147975 DOI: 10.1007/s10393-017-1278-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/07/2017] [Accepted: 08/07/2017] [Indexed: 06/07/2023]
Abstract
Amphibians are experiencing devastating population declines globally. A major driver is chytridiomycosis, an emerging infectious disease caused by the fungal pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal). Bd was described in 1999 and has been linked with declines since the 1970s, while Bsal is a more recently discovered pathogen that was described in 2013. It is hypothesized that Bsal originated in Asia and spread via international trade to Europe, where it has been linked to salamander die-offs. Trade in live amphibians thus represents a significant threat to global biodiversity in amphibians. We review the current state of knowledge regarding Bsal and describe the risk of Bsal spread. We discuss regional responses to Bsal and barriers that impede a rapid, coordinated global effort. The discovery of a second deadly emerging chytrid fungal pathogen in amphibians poses an opportunity for scientists, conservationists, and governments to improve global biosecurity and further protect humans and wildlife from a growing number of emerging infectious diseases.
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Affiliation(s)
- Tiffany A Yap
- Department of Biology, San Francisco State University, Hensill Hall, 1600 Holloway Avenue, San Francisco, CA, 94132, USA.
- Museum of Vertebrate Zoology, University of California Berkeley, 3101 Valley Life Sciences Building, Berkeley, CA, 94720, USA.
| | - Natalie T Nguyen
- U.S. Geological Survey National Wildlife Health Center, 6006 Schroeder Rd., Madison, WI, 53711, USA
| | - Megan Serr
- Department of Biological Sciences, North Carolina State University, Thomas Hall, 1100 Brooks Avenue, Raleigh, NC, 27695, USA
| | - Alexander Shepack
- Zoology Department, Southern Illinois University Carbondale, 1125 Lincoln Drive, Carbondale, IL, 62901, USA
| | - Vance T Vredenburg
- Department of Biology, San Francisco State University, Hensill Hall, 1600 Holloway Avenue, San Francisco, CA, 94132, USA
- Museum of Vertebrate Zoology, University of California Berkeley, 3101 Valley Life Sciences Building, Berkeley, CA, 94720, USA
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29
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Garner TWJ, Schmidt BR, Martel A, Pasmans F, Muths E, Cunningham AA, Weldon C, Fisher MC, Bosch J. Mitigating amphibian chytridiomycoses in nature. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2016.0207. [PMID: 28080996 DOI: 10.1098/rstb.2016.0207] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/12/2016] [Indexed: 12/11/2022] Open
Abstract
Amphibians across the planet face the threat of population decline and extirpation caused by the disease chytridiomycosis. Despite consensus that the fungal pathogens responsible for the disease are conservation issues, strategies to mitigate their impacts in the natural world are, at best, nascent. Reducing risk associated with the movement of amphibians, non-amphibian vectors and other sources of infection remains the first line of defence and a primary objective when mitigating the threat of disease in wildlife. Amphibian-associated chytridiomycete fungi and chytridiomycosis are already widespread, though, and we therefore focus on discussing options for mitigating the threats once disease emergence has occurred in wild amphibian populations. All strategies have shortcomings that need to be overcome before implementation, including stronger efforts towards understanding and addressing ethical and legal considerations. Even if these issues can be dealt with, all currently available approaches, or those under discussion, are unlikely to yield the desired conservation outcome of disease mitigation. The decision process for establishing mitigation strategies requires integrated thinking that assesses disease mitigation options critically and embeds them within more comprehensive strategies for the conservation of amphibian populations, communities and ecosystems.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'.
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Affiliation(s)
- Trenton W J Garner
- Institute of Zoology, Zoological Society of London, Regents Park, NW1 4RY London, UK .,Unit for Environmental Research and Management, North-West University, Potchefstroom 2520, South Africa
| | - Benedikt R Schmidt
- Karch, Passage Maximilien-de-Meuron 6, 2000 Neuchâtel, Switzerland.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - Erin Muths
- U.S. Geological Survey, Fort Collins Science Fort Collins, 2150 Centre Avenue Building C, Fort Collins, CO 80526, USA
| | - Andrew A Cunningham
- Institute of Zoology, Zoological Society of London, Regents Park, NW1 4RY London, UK
| | - Che Weldon
- Unit for Environmental Research and Management, North-West University, Potchefstroom 2520, South Africa
| | - Matthew C Fisher
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Jaime Bosch
- Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, 28006 Madrid, Spain
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30
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More S, Bøtner A, Butterworth A, Calistri P, Depner K, Edwards S, Garin-Bastuji B, Good M, Gortázar Schmidt C, Michel V, Miranda MA, Nielsen SS, Raj M, Sihvonen L, Spoolder H, Stegeman JA, Thulke HH, Velarde A, Willeberg P, Winckler C, Baldinelli F, Broglia A, Candiani D, Fabris C, Georgiadis M, Zancanaro G, Beltrán-Beck B, Kohnle L, Bicout D. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): Batrachochytrium salamandrivorans ( Bsal). EFSA J 2017; 15:e05071. [PMID: 32625359 PMCID: PMC7010176 DOI: 10.2903/j.efsa.2017.5071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Batrachochytrium salamandrivorans (Bsal) has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of Bsal to be listed, Article 9 for the categorisation of Bsal according to disease prevention and control rules as in Annex IV, and Article 8 on the list of animal species related to Bsal. The assessment has been performed following a methodology composed of information collection and compilation, expert judgement on each criterion at individual and, if no consensus was reached before, also at collective level. The output is composed of the categorical answer, and for the questions where no consensus was reached, the different supporting views are reported. Details on the methodology used for this assessment are explained in a separate opinion. According to the assessment performed, Bsal can be considered eligible to be listed for Union intervention as laid down in Article 5(3) of the AHL. The disease would comply with the criteria as in sections 4 and 5 of Annex IV of the AHL, for the application of the disease prevention and control rules referred to in points (d) and (e) of Article 9(1). The assessment here performed on compliance with the criteria as in Section 1 of Annex IV referred to in point (a) of Article 9(1) is inconclusive. The animal species to be listed for Bsal according to Article 8(3) criteria are species of the families Salamandridae and Plethodontidae as susceptible and Salamandridae and Hynobiidae as reservoirs.
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31
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Drivers of salamander extirpation mediated by Batrachochytrium salamandrivorans. Nature 2017; 544:353-356. [PMID: 28425998 DOI: 10.1038/nature22059] [Citation(s) in RCA: 142] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 03/13/2017] [Indexed: 11/08/2022]
Abstract
The recent arrival of Batrachochytrium salamandrivorans in Europe was followed by rapid expansion of its geographical distribution and host range, confirming the unprecedented threat that this chytrid fungus poses to western Palaearctic amphibians. Mitigating this hazard requires a thorough understanding of the pathogen's disease ecology that is driving the extinction process. Here, we monitored infection, disease and host population dynamics in a Belgian fire salamander (Salamandra salamandra) population for two years immediately after the first signs of infection. We show that arrival of this chytrid is associated with rapid population collapse without any sign of recovery, largely due to lack of increased resistance in the surviving salamanders and a demographic shift that prevents compensation for mortality. The pathogen adopts a dual transmission strategy, with environmentally resistant non-motile spores in addition to the motile spores identified in its sister species B. dendrobatidis. The fungus retains its virulence not only in water and soil, but also in anurans and less susceptible urodelan species that function as infection reservoirs. The combined characteristics of the disease ecology suggest that further expansion of this fungus will behave as a 'perfect storm' that is able to rapidly extirpate highly susceptible salamander populations across Europe.
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32
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Parrott JC, Shepack A, Burkart D, LaBumbard B, Scimè P, Baruch E, Catenazzi A. Survey of Pathogenic Chytrid Fungi (Batrachochytrium dendrobatidis and B. salamandrivorans) in Salamanders from Three Mountain Ranges in Europe and the Americas. ECOHEALTH 2017; 14:296-302. [PMID: 27709310 DOI: 10.1007/s10393-016-1188-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 09/13/2016] [Accepted: 09/14/2016] [Indexed: 06/06/2023]
Abstract
Batrachochytrium salamandrivorans (Bsal) is a virulent fungal pathogen that infects salamanders. It is implicated in the recent collapse of several populations of fire salamanders in Europe. This pathogen seems much like that of its sister species, Batrachochytrium dendrobatidis (Bd), the agent responsible for anuran extinctions and extirpations worldwide, and is considered to be an emerging global threat to salamander communities. Bsal thrives at temperatures found in many mountainous regions rich in salamander species; because of this, we have screened specimens of salamanders representing 17 species inhabiting mountain ranges in three continents: The Smoky Mountains, the Swiss Alps, and the Peruvian Andes. We screened 509 salamanders, with 192 representing New World salamanders that were never tested for Bsal previously. Bsal was not detected, and Bd was mostly present at low prevalence except for one site in the Andes.
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Affiliation(s)
- Joshua Curtis Parrott
- Zoology Department, Southern Illinois University Carbondale, 1125 Lincoln drive, Carbondale, IL, 62901, USA.
| | - Alexander Shepack
- Zoology Department, Southern Illinois University Carbondale, 1125 Lincoln drive, Carbondale, IL, 62901, USA
| | - David Burkart
- Zoology Department, Southern Illinois University Carbondale, 1125 Lincoln drive, Carbondale, IL, 62901, USA
| | - Brandon LaBumbard
- Zoology Department, Southern Illinois University Carbondale, 1125 Lincoln drive, Carbondale, IL, 62901, USA
- University of Massachusetts Boston, Boston, MA, USA
| | | | - Ethan Baruch
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85281, USA
| | - Alessandro Catenazzi
- Zoology Department, Southern Illinois University Carbondale, 1125 Lincoln drive, Carbondale, IL, 62901, USA
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33
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Batrachochytrium salamandrivorans is the predominant chytrid fungus in Vietnamese salamanders. Sci Rep 2017; 7:44443. [PMID: 28287614 PMCID: PMC5347381 DOI: 10.1038/srep44443] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 02/08/2017] [Indexed: 11/08/2022] Open
Abstract
The amphibian chytrid fungi, Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), pose a major threat to amphibian biodiversity. Recent evidence suggests Southeast Asia as a potential cradle for both fungi, which likely resulted in widespread host-pathogen co-existence. We sampled 583 salamanders from 8 species across Vietnam in 55 locations for Bsal and Bd, determined scaled mass index as a proxy for fitness and collected environmental data. Bsal was found within 14 of the 55 habitats (2 of which it was detected in 2013), in 5 salamandrid species, with a prevalence of 2.92%. The globalized pandemic lineage of Bd was found within one pond on one species with a prevalence of 0.69%. Combined with a complete lack of correlation between infection and individual body condition and absence of indication of associated disease, this suggests low level pathogen endemism and Bsal and Bd co-existence with Vietnamese salamandrid populations. Bsal was more widespread than Bd, and occurs at temperatures higher than tolerated by the type strain, suggesting a wider thermal niche than currently known. Therefore, this study provides support for the hypothesis that these chytrid fungi may be endemic to Asia and that species within this region may act as a disease reservoir.
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34
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Balàž V, Gortázar Schmidt C, Murray K, Carnesecchi E, Garcia A, Gervelmeyer A, Martino L, Munoz Guajardo I, Verdonck F, Zancanaro G, Fabris C. Scientific and technical assistance concerning the survival, establishment and spread of Batrachochytrium salamandrivorans (Bsal) in the EU. EFSA J 2017; 15:e04739. [PMID: 32625419 PMCID: PMC7010177 DOI: 10.2903/j.efsa.2017.4739] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A new fungus, Batrachochytrium salamandrivorans (Bsal), was identified in wild populations of salamanders in the Netherlands and Belgium, and in kept salamander populations in Germany and the United Kingdom. EFSA assessed the potential of Bsal to affect the health of wild and kept salamanders in the EU, the effectiveness and feasibility of a movement ban of traded salamanders, the validity, reliability and robustness of available diagnostic methods for Bsal detection, and possible alternative methods and feasible risk mitigation measures to ensure safe international and EU trade of salamanders and their products. Bsal was isolated and characterised in 2013 from a declining fire salamander (Salamandra salamandra) population in the Netherlands. Based on the available evidence, it is likely that Bsal is a sufficient cause for the death of S. salamandra both in the laboratory and in the wild. Despite small sample sizes, the available experimental evidence indicates that Bsal is associated with disease and death in individuals of 12 European and 3 Asian salamander species, and with high mortality rate outbreaks in kept salamanders. Bsal experimental infection was detected in individuals of at least one species pertaining to the families Salamandridae, Plethodontidae, Hynobiidae and Sirenidae. Movement bans constitute key risk mitigation measures to prevent pathogen spread into naïve areas and populations. The effectiveness of a movement ban is mainly dependent on the import volumes, possibility of Bsal to remain viable outside susceptible/tolerant species, and the capacity to limit illegal movements. Duplex real-time PCR can be used to detect Bsal DNA, but has not been fully validated. Quarantining salamanders, enacting legislation that requires testing of animals to demonstrate freedom from Bsal, before movement can take place, restricting salamander movements, tracking all traded species, hygienic procedures/biosecurity measures before and during movements, and increasing public awareness are relevant measures for ensuring safe intra-EU and international trade of salamanders.
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Feldmeier S, Schefczyk L, Wagner N, Heinemann G, Veith M, Lötters S. Exploring the Distribution of the Spreading Lethal Salamander Chytrid Fungus in Its Invasive Range in Europe - A Macroecological Approach. PLoS One 2016; 11:e0165682. [PMID: 27798698 PMCID: PMC5087956 DOI: 10.1371/journal.pone.0165682] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 10/14/2016] [Indexed: 12/11/2022] Open
Abstract
The chytrid fungus Batrachochytrium salamandrivorans (Bsal) is a dangerous pathogen to salamanders and newts. Apparently native to Asia, it has recently been detected in Western Europe where it is expected to spread and to have dramatic effects on naïve hosts. Since 2010, Bsal has led to some catastrophic population declines of urodeles in the Netherlands and Belgium. More recently, it has been discovered in additional, more distant sites including sites in Germany. With the purpose to contribute to a better understanding of Bsal, we modelled its potential distribution in its invasive European range to gain insights about the factors driving this distribution. We computed Bsal Maxent models for two predictor sets, which represent different temporal resolutions, using three different background extents to account for different invasion stage scenarios. Beside 'classical' bioclimate, we employed weather data, which allowed us to emphasize predictors in accordance with the known pathogen's biology. The most important predictors as well as spatial predictions varied between invasion scenarios and predictor sets. The most reasonable model was based on weather data and the scenario of a recent pathogen introduction. It identified temperature predictors, which represent optimal growing conditions and heat limiting conditions, as the most explaining drivers of the current distribution. This model also predicted large areas in the study region as suitable for Bsal. The other models predicted considerably less, but shared some areas which we interpreted as most likely high risk zones. Our results indicate that growth relevant temperatures measured under laboratory conditions might also be relevant on a macroecological scale, if predictors with a high temporal resolution and relevance are used. Additionally, the conditions in our study area support the possibility of a further Bsal spread, especially when considering that our models might tend to underestimate the potential distribution of Bsal.
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Affiliation(s)
| | - Lukas Schefczyk
- Department of Environmental Meteorology, Trier University, Trier, Germany
| | - Norman Wagner
- Department of Biogeography, Trier University, Trier, Germany
| | - Günther Heinemann
- Department of Environmental Meteorology, Trier University, Trier, Germany
| | - Michael Veith
- Department of Biogeography, Trier University, Trier, Germany
| | - Stefan Lötters
- Department of Biogeography, Trier University, Trier, Germany
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Rebollar EA, Antwis RE, Becker MH, Belden LK, Bletz MC, Brucker RM, Harrison XA, Hughey MC, Kueneman JG, Loudon AH, McKenzie V, Medina D, Minbiole KPC, Rollins-Smith LA, Walke JB, Weiss S, Woodhams DC, Harris RN. Using "Omics" and Integrated Multi-Omics Approaches to Guide Probiotic Selection to Mitigate Chytridiomycosis and Other Emerging Infectious Diseases. Front Microbiol 2016; 7:68. [PMID: 26870025 PMCID: PMC4735675 DOI: 10.3389/fmicb.2016.00068] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 01/14/2016] [Indexed: 12/20/2022] Open
Abstract
Emerging infectious diseases in wildlife are responsible for massive population declines. In amphibians, chytridiomycosis caused by Batrachochytrium dendrobatidis, Bd, has severely affected many amphibian populations and species around the world. One promising management strategy is probiotic bioaugmentation of antifungal bacteria on amphibian skin. In vivo experimental trials using bioaugmentation strategies have had mixed results, and therefore a more informed strategy is needed to select successful probiotic candidates. Metagenomic, transcriptomic, and metabolomic methods, colloquially called "omics," are approaches that can better inform probiotic selection and optimize selection protocols. The integration of multiple omic data using bioinformatic and statistical tools and in silico models that link bacterial community structure with bacterial defensive function can allow the identification of species involved in pathogen inhibition. We recommend using 16S rRNA gene amplicon sequencing and methods such as indicator species analysis, the Kolmogorov-Smirnov Measure, and co-occurrence networks to identify bacteria that are associated with pathogen resistance in field surveys and experimental trials. In addition to 16S amplicon sequencing, we recommend approaches that give insight into symbiont function such as shotgun metagenomics, metatranscriptomics, or metabolomics to maximize the probability of finding effective probiotic candidates, which can then be isolated in culture and tested in persistence and clinical trials. An effective mitigation strategy to ameliorate chytridiomycosis and other emerging infectious diseases is necessary; the advancement of omic methods and the integration of multiple omic data provide a promising avenue toward conservation of imperiled species.
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Affiliation(s)
- Eria A. Rebollar
- Department of Biology, James Madison UniversityHarrisonburg, VA, USA
| | - Rachael E. Antwis
- Unit for Environmental Sciences and Management, North-West UniversityPotchefstroom, South Africa
- Institute of Zoology, Zoological Society of LondonLondon, UK
- School of Environment and Life Sciences, University of SalfordSalford, UK
| | - Matthew H. Becker
- Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological ParkWashington, DC, USA
| | - Lisa K. Belden
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | - Molly C. Bletz
- Zoological Institute, Technische Universität BraunschweigBraunschweig, Germany
| | | | | | - Myra C. Hughey
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | - Jordan G. Kueneman
- Department of Ecology and Evolutionary Biology, University of ColoradoBoulder, CO, USA
| | - Andrew H. Loudon
- Department of Zoology, Biodiversity Research Centre, University of British ColumbiaVancouver, BC, Canada
| | - Valerie McKenzie
- Department of Ecology and Evolutionary Biology, University of ColoradoBoulder, CO, USA
| | - Daniel Medina
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | | | - Louise A. Rollins-Smith
- Department of Pathology, Microbiology and Immunology and Department of Pediatrics, Vanderbilt University School of Medicine, Department of Biological Sciences, Vanderbilt UniversityNashville, TN, USA
| | - Jenifer B. Walke
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | - Sophie Weiss
- Department of Chemical and Biological Engineering, University of Colorado at BoulderBoulder, CO, USA
| | | | - Reid N. Harris
- Department of Biology, James Madison UniversityHarrisonburg, VA, USA
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Richgels KLD, Russell RE, Adams MJ, White CL, Grant EHC. Spatial variation in risk and consequence of Batrachochytrium salamandrivorans introduction in the USA. ROYAL SOCIETY OPEN SCIENCE 2016; 3:150616. [PMID: 26998331 PMCID: PMC4785982 DOI: 10.1098/rsos.150616] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 01/22/2016] [Indexed: 05/07/2023]
Abstract
A newly identified fungal pathogen, Batrachochytrium salamandrivorans(Bsal), is responsible for mass mortality events and severe population declines in European salamanders. The eastern USA has the highest diversity of salamanders in the world and the introduction of this pathogen is likely to be devastating. Although data are inevitably limited for new pathogens, disease-risk assessments use best available data to inform management decisions. Using characteristics of Bsalecology, spatial data on imports and pet trade establishments, and salamander species diversity, we identify high-risk areas with both a high likelihood of introduction and severe consequences for local salamanders. We predict that the Pacific coast, southern Appalachian Mountains and mid-Atlantic regions will have the highest relative risk from Bsal. Management of invasive pathogens becomes difficult once they are established in wildlife populations; therefore, import restrictions to limit pathogen introduction and early detection through surveillance of high-risk areas are priorities for preventing the next crisis for North American salamanders.
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Affiliation(s)
- Katherine L. D. Richgels
- US Geological Survey National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711, USA
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin—Madison, 2015 Linden Drive, Madison, WI 53706, USA
- Author for correspondence: Katherine L. D. Richgels e-mail:
| | - Robin E. Russell
- US Geological Survey National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711, USA
| | - Michael J. Adams
- US Geological Survey Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, OR 97331, USA
| | - C. LeAnn White
- US Geological Survey National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711, USA
| | - Evan H. Campbell Grant
- US Geological Survey Patuxent Wildlife Research Center, SO Conte Anadromous Fish Research Laboratory, 1 Migratory Way, Turner Falls, MA 01376, USA
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Van Rooij P, Martel A, Haesebrouck F, Pasmans F. Amphibian chytridiomycosis: a review with focus on fungus-host interactions. Vet Res 2015; 46:137. [PMID: 26607488 PMCID: PMC4660679 DOI: 10.1186/s13567-015-0266-0] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/05/2015] [Indexed: 01/30/2023] Open
Abstract
Amphibian declines and extinctions are emblematic for the current sixth mass extinction event. Infectious drivers of these declines include the recently emerged fungal pathogens Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans (Chytridiomycota). The skin disease caused by these fungi is named chytridiomycosis and affects the vital function of amphibian skin. Not all amphibians respond equally to infection and host responses might range from resistant, over tolerant to susceptible. The clinical outcome of infection is highly dependent on the amphibian host, the fungal virulence and environmental determinants. B. dendrobatidis infects the skin of a large range of anurans, urodeles and caecilians, whereas to date the host range of B. salamandrivorans seems limited to urodeles. So far, the epidemic of B. dendrobatidis is mainly limited to Australian, neotropical, South European and West American amphibians, while for B. salamandrivorans it is limited to European salamanders. Other striking differences between both fungi include gross pathology and thermal preferences. With this review we aim to provide the reader with a state-of-the art of host-pathogen interactions for both fungi, in which new data pertaining to the interaction of B. dendrobatidis and B. salamandrivorans with the host’s skin are integrated. Furthermore, we pinpoint areas in which more detailed studies are necessary or which have not received the attention they merit.
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Affiliation(s)
- Pascale Van Rooij
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - An Martel
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Freddy Haesebrouck
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Frank Pasmans
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
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Blooi M, Pasmans F, Rouffaer L, Haesebrouck F, Vercammen F, Martel A. Successful treatment of Batrachochytrium salamandrivorans infections in salamanders requires synergy between voriconazole, polymyxin E and temperature. Sci Rep 2015; 5:11788. [PMID: 26123899 PMCID: PMC4485233 DOI: 10.1038/srep11788] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/03/2015] [Indexed: 12/13/2022] Open
Abstract
Chytridiomycosis caused by the chytrid fungus Batrachochytrium salamandrivorans (Bsal) poses a serious threat to urodelan diversity worldwide. Antimycotic treatment of this disease using protocols developed for the related fungus Batrachochytrium dendrobatidis (Bd), results in therapeutic failure. Here, we reveal that this therapeutic failure is partly due to different minimum inhibitory concentrations (MICs) of antimycotics against Bsal and Bd. In vitro growth inhibition of Bsal occurs after exposure to voriconazole, polymyxin E, itraconazole and terbinafine but not to florfenicol. Synergistic effects between polymyxin E and voriconazole or itraconazole significantly decreased the combined MICs necessary to inhibit Bsal growth. Topical treatment of infected fire salamanders (Salamandra salamandra), with voriconazole or itraconazole alone (12.5 μg/ml and 0.6 μg/ml respectively) or in combination with polymyxin E (2000 IU/ml) at an ambient temperature of 15 °C during 10 days decreased fungal loads but did not clear Bsal infections. However, topical treatment of Bsal infected animals with a combination of polymyxin E (2000 IU/ml) and voriconazole (12.5 μg/ml) at an ambient temperature of 20 °C resulted in clearance of Bsal infections. This treatment protocol was validated in 12 fire salamanders infected with Bsal during a field outbreak and resulted in clearance of infection in all animals.
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Affiliation(s)
- M Blooi
- 1] Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium [2] Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
| | - F Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - L Rouffaer
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - F Haesebrouck
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - F Vercammen
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
| | - A Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
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Sabino-Pinto J, Bletz M, Hendrix R, Perl RB, Martel A, Pasmans F, Lötters S, Mutschmann F, Schmeller DS, Schmidt BR, Veith M, Wagner N, Vences M, Steinfartz S. First detection of the emerging fungal pathogen Batrachochytrium salamandrivorans in Germany. AMPHIBIA-REPTILIA 2015. [DOI: 10.1163/15685381-00003008] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The emerging infectious disease chytridiomycosis is one of the major factors triggering global amphibian declines. A recently discovered species of chytrid fungus,Batrachochytrium salamandrivorans(Bsal), likely originated in East Asia, has led to massive declines in populations of fire salamanders (Salamandra salamandra) after its apparent introduction to the Netherlands and Belgium. Here, we report the first detection of this pathogen in Germany where it caused mass mortality of fire salamanders in a captive collection. Salamanders from this collection showed an almost 100% prevalence of infection withBsal. SupposedBsal-induced mortality occurred in multipleSalamandraspecies (S. salamandra,S. algira,S. corsica, andS. infraimmaculata), whileBsalinfection was confirmed in nine subspecies ofS. salamandraand inS. algira. Our study indicates that this pathogen can potentially infect all fire salamander species and subspecies. IfBsalspreads from captive collections to wild populations, then a similar devastating effect associated with high mortality should be expected.
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Affiliation(s)
- Joana Sabino-Pinto
- Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Molly Bletz
- Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Ralf Hendrix
- Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - R.G. Bina Perl
- Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Stefan Lötters
- Department of Biogeography, Trier University, Trier, Germany
| | - Frank Mutschmann
- Exomed – Institut für veterinärmedizinische Betreuung niederer Wirbeltiere und Exoten, Berlin, Germany
| | - Dirk S. Schmeller
- UFZ – Helmholtz Centre for Environmental Research, Department of Conservation Biology, Leipzig, Germany
| | - Benedikt R. Schmidt
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- KARCH, Neuchâtel, Switzerland
| | - Michael Veith
- Department of Biogeography, Trier University, Trier, Germany
| | - Norman Wagner
- Department of Biogeography, Trier University, Trier, Germany
| | - Miguel Vences
- Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Sebastian Steinfartz
- Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
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