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David S Blehert - One of the best experts on this subject based on the ideXlab platform.
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pathophysiology of white nose syndrome in bats a mechanistic model linking wing damage to mortality
Biology Letters, 2013Co-Authors: Lisa Warnecke, David S Blehert, Paul M Cryan, Gudrun Wibbelt, James M Turner, Trent K Bollinger, Vikram Misra, Craig K R WillisAbstract:White-nose syndrome is devastating North American bat populations but we lack basic information on disease mechanisms. Altered blood physiology owing to epidermal invasion by the fungal pathogen Geomyces destructans (Gd) has been hypothesized as a cause of disrupted torpor patterns of affected hibernating bats, leading to mortality. Here, we present data on blood electrolyte concentration, haematology and acid-base balance of hibernating little brown bats, Myotis lucifugus, following experimental inoculation with Gd. Compared with controls, infected bats showed electrolyte depletion (i.e. lower plasma sodium), changes in haematology (i.e. increased haematocrit and decreased glucose) and disrupted acid-base balance (i.e. lower CO2 partial pressure and bicarbonate). These findings indicate hypotonic dehydration, hypovolaemia and metabolic acidosis. We propose a mechanistic model linking tissue damage to altered homeostasis and morbidity/mortality.
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a culture based survey of fungi in soil from bat hibernacula in the eastern united states and its implications for detection of Geomyces destructans the causal agent of bat white nose syndrome
Mycologia, 2013Co-Authors: Jeffrey M Lorch, Andrea Gargas, Andrew M Minnis, Daniel L Lindner, Laura K Muller, David S BlehertAbstract:The recent emergence of white-nose syn- drome (WNS), a fungal disease causing unprecedent- ed mortality among hibernating bats of eastern North America, has revealed a knowledge gap regarding fungal communities associated with bats and their hibernacula. We used culture-based techniques to investigate the diversity of fungi in soil samples collected from 24 bat hibernacula in the eastern United States. Ribosomal RNA regions (internal transcribed spacer and partial intergenic spacer) were sequenced to preliminarily characterize isolates. Geomyces species were one of the most abundant and diverse groups cultured, representing approxi- mately 33% of all isolates. Geomyces destructans was isolated from soil samples from three hibernacula in states where WNS is known to occur, and many of the other cultured Geomyces isolates likely represent undescribed taxa. Further characterization of the diversity of fungi that occur in hibernacula both will facilitate an improved understanding of the ecology
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a culture based survey of fungi in soil from bat hibernacula in the eastern united states and its implications for detection of Geomyces destructans the causal agent of bat white nose syndrome
Mycologia, 2013Co-Authors: Jeffrey M Lorch, Andrea Gargas, Andrew M Minnis, Daniel L Lindner, Laura K Muller, David S BlehertAbstract:The recent emergence of white-nose syndrome (WNS), a fungal disease causing unprecedented mortality among hibernating bats of eastern North America, has revealed a knowledge gap regarding fungal communities associated with bats and their hibernacula. We used culture-based techniques to investigate the diversity of fungi in soil samples collected from 24 bat hibernacula in the eastern United States. Ribosomal RNA regions (internal transcribed spacer and partial intergenic spacer) were sequenced to preliminarily characterize isolates. Geomyces species were one of the most abundant and diverse groups cultured, representing approximately 33% of all isolates. Geomyces destructans was isolated from soil samples from three hibernacula in states where WNS is known to occur, and many of the other cultured Geomyces isolates likely represent undescribed taxa. Further characterization of the diversity of fungi that occur in hibernacula both will facilitate an improved understanding of the ecology of G. destructans within this complex fungal community and provide an opportunity to identify characteristics that differentiate G. destructans from non-pathogenic relatives.
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bat white nose syndrome a real time taqman polymerase chain reaction test targeting the intergenic spacer region of Geomyces destructans
Mycologia, 2013Co-Authors: Laura K Muller, Jeffrey M Lorch, Andrea Gargas, Daniel L Lindner, Michael Oconnor, David S BlehertAbstract:The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The test is highly sensitive, consistently detecting as little as 3.3 fg genomic DNA from G. destructans. The real-time PCR test specifically amplified genomic DNA from G. destructans but did not amplify target sequence from 54 closely related fungal isolates (including 43 Geomyces spp. isolates) associated with bats. The test was qualified further by analyzing DNA extracted from 91 bat wing skin samples, and PCR results matched histopathology findings. These data indicate the real-time TaqMan PCR method described herein is a sensitive, specific and rapid test to detect DNA from G. destructans and provides a valuable tool for WNS diagnostics and research.
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distribution and environmental persistence of the causative agent of white nose syndrome Geomyces destructans in bat hibernacula of the eastern united states
Applied and Environmental Microbiology, 2013Co-Authors: Jeffrey M Lorch, Daniel L Lindner, Laura K Muller, Michael Oconnor, Robin E Russell, David S BlehertAbstract:ABSTRACT White-nose syndrome (WNS) is an emerging disease of hibernating bats caused by the recently described fungus Geomyces destructans. First isolated in 2008, the origins of this fungus in North America and its ability to persist in the environment remain undefined. To investigate the correlation between manifestation of WNS and distribution of G. destructans in the United States, we analyzed sediment samples collected from 55 bat hibernacula (caves and mines) both within and outside the known range of WNS using a newly developed real-time PCR assay. Geomyces destructans was detected in 17 of 21 sites within the known range of WNS at the time when the samples were collected; the fungus was not found in 28 sites beyond the known range of the disease at the time when environmental samples were collected. These data indicate that the distribution of G. destructans is correlated with disease in hibernating bats and support the hypothesis that the fungus is likely an exotic species in North America. Additionally, we examined whether G. destructans persists in infested bat hibernacula when bats are absent. Sediment samples were collected from 14 WNS-positive hibernacula, and the samples were screened for viable fungus by using a culture technique. Viable G. destructans was cultivated from 7 of the 14 sites sampled during late summer, when bats were no longer in hibernation, suggesting that the fungus can persist in the environment in the absence of bat hosts for long periods of time.
Jeffrey M Lorch - One of the best experts on this subject based on the ideXlab platform.
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a culture based survey of fungi in soil from bat hibernacula in the eastern united states and its implications for detection of Geomyces destructans the causal agent of bat white nose syndrome
Mycologia, 2013Co-Authors: Jeffrey M Lorch, Andrea Gargas, Andrew M Minnis, Daniel L Lindner, Laura K Muller, David S BlehertAbstract:The recent emergence of white-nose syn- drome (WNS), a fungal disease causing unprecedent- ed mortality among hibernating bats of eastern North America, has revealed a knowledge gap regarding fungal communities associated with bats and their hibernacula. We used culture-based techniques to investigate the diversity of fungi in soil samples collected from 24 bat hibernacula in the eastern United States. Ribosomal RNA regions (internal transcribed spacer and partial intergenic spacer) were sequenced to preliminarily characterize isolates. Geomyces species were one of the most abundant and diverse groups cultured, representing approxi- mately 33% of all isolates. Geomyces destructans was isolated from soil samples from three hibernacula in states where WNS is known to occur, and many of the other cultured Geomyces isolates likely represent undescribed taxa. Further characterization of the diversity of fungi that occur in hibernacula both will facilitate an improved understanding of the ecology
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a culture based survey of fungi in soil from bat hibernacula in the eastern united states and its implications for detection of Geomyces destructans the causal agent of bat white nose syndrome
Mycologia, 2013Co-Authors: Jeffrey M Lorch, Andrea Gargas, Andrew M Minnis, Daniel L Lindner, Laura K Muller, David S BlehertAbstract:The recent emergence of white-nose syndrome (WNS), a fungal disease causing unprecedented mortality among hibernating bats of eastern North America, has revealed a knowledge gap regarding fungal communities associated with bats and their hibernacula. We used culture-based techniques to investigate the diversity of fungi in soil samples collected from 24 bat hibernacula in the eastern United States. Ribosomal RNA regions (internal transcribed spacer and partial intergenic spacer) were sequenced to preliminarily characterize isolates. Geomyces species were one of the most abundant and diverse groups cultured, representing approximately 33% of all isolates. Geomyces destructans was isolated from soil samples from three hibernacula in states where WNS is known to occur, and many of the other cultured Geomyces isolates likely represent undescribed taxa. Further characterization of the diversity of fungi that occur in hibernacula both will facilitate an improved understanding of the ecology of G. destructans within this complex fungal community and provide an opportunity to identify characteristics that differentiate G. destructans from non-pathogenic relatives.
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bat white nose syndrome a real time taqman polymerase chain reaction test targeting the intergenic spacer region of Geomyces destructans
Mycologia, 2013Co-Authors: Laura K Muller, Jeffrey M Lorch, Andrea Gargas, Daniel L Lindner, Michael Oconnor, David S BlehertAbstract:The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The test is highly sensitive, consistently detecting as little as 3.3 fg genomic DNA from G. destructans. The real-time PCR test specifically amplified genomic DNA from G. destructans but did not amplify target sequence from 54 closely related fungal isolates (including 43 Geomyces spp. isolates) associated with bats. The test was qualified further by analyzing DNA extracted from 91 bat wing skin samples, and PCR results matched histopathology findings. These data indicate the real-time TaqMan PCR method described herein is a sensitive, specific and rapid test to detect DNA from G. destructans and provides a valuable tool for WNS diagnostics and research.
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distribution and environmental persistence of the causative agent of white nose syndrome Geomyces destructans in bat hibernacula of the eastern united states
Applied and Environmental Microbiology, 2013Co-Authors: Jeffrey M Lorch, Daniel L Lindner, Laura K Muller, Michael Oconnor, Robin E Russell, David S BlehertAbstract:ABSTRACT White-nose syndrome (WNS) is an emerging disease of hibernating bats caused by the recently described fungus Geomyces destructans. First isolated in 2008, the origins of this fungus in North America and its ability to persist in the environment remain undefined. To investigate the correlation between manifestation of WNS and distribution of G. destructans in the United States, we analyzed sediment samples collected from 55 bat hibernacula (caves and mines) both within and outside the known range of WNS using a newly developed real-time PCR assay. Geomyces destructans was detected in 17 of 21 sites within the known range of WNS at the time when the samples were collected; the fungus was not found in 28 sites beyond the known range of the disease at the time when environmental samples were collected. These data indicate that the distribution of G. destructans is correlated with disease in hibernating bats and support the hypothesis that the fungus is likely an exotic species in North America. Additionally, we examined whether G. destructans persists in infested bat hibernacula when bats are absent. Sediment samples were collected from 14 WNS-positive hibernacula, and the samples were screened for viable fungus by using a culture technique. Viable G. destructans was cultivated from 7 of the 14 sites sampled during late summer, when bats were no longer in hibernation, suggesting that the fungus can persist in the environment in the absence of bat hosts for long periods of time.
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inoculation of bats with european Geomyces destructans supports the novel pathogen hypothesis for the origin of white nose syndrome
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Lisa Warnecke, Jeffrey M Lorch, Vikram Misra, James M Turne, Tre K Ollinge, Paul M Crya, Gudru Wibbel, David S Lehe, Craig K R WillisAbstract:White-nose syndrome (WNS) is an emerging disease of hibernating bats associated with cutaneous infection by the fungus Geomyces destructans (Gd), and responsible for devastating declines of bat populations in eastern North America. Affected bats appear emaciated and one hypothesis is that they spend too much time out of torpor during hibernation, depleting vital fat reserves required to survive the winter. The fungus has also been found at low levels on bats throughout Europe but without mass mortality. This finding suggests that Gd is either native to both continents but has been rendered more pathogenic in North America by mutation or environmental change, or that it recently arrived in North America as an invader from Europe. Thus, a causal link between Gd and mortality has not been established and the reason for its high pathogenicity in North America is unknown. Here we show that experimental inoculation with either North American or European isolates of Gd causes WNS and mortality in the North American bat, Myotis lucifugus. In contrast to control bats, individuals inoculated with either isolate of Gd developed cutaneous infections diagnostic of WNS, exhibited a progressive increase in the frequency of arousals from torpor during hibernation, and were emaciated after 3–4 mo. Our results demonstrate that altered torpor-arousal cycles underlie mortality from WNS and provide direct evidence that Gd is a novel pathogen to North America from Europe.
Vishnu Chaturvedi - One of the best experts on this subject based on the ideXlab platform.
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draft genome sequences of human pathogenic fungus Geomyces pannorum sensu lato and bat white nose syndrome pathogen Geomyces pseudogymnoascus destructans
Genome Announcements, 2013Co-Authors: Marcus C Chibucos, Jonathan Crabtree, Sushma Nagaraj, Sudha Chaturvedi, Vishnu ChaturvediAbstract:ABSTRACT We report the draft genome sequences of Geomyces pannorum sensu lato and Geomyces (Pseudogymnoascus) destructans. G. pannorum has a larger proteome than G. destructans, containing more proteins with ascribed enzymatic functions. This dichotomy in the genomes of related psychrophilic fungi is a valuable target for defining their distinct saprobic and pathogenic attributes.
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clonal spread of Geomyces destructans among bats midwestern and southern united states
Emerging Infectious Diseases, 2012Co-Authors: Ping Ren, Vishnu Chaturvedi, Sunanda S Rajkumar, Katie H Haman, Kevin M KeelAbstract:To the Editor: Bat geomycosis (white nose syndrome) is caused by the psychrophilic fungus Geomyces destructans, which has rapidly spread in the United States and Canada since it was first reported from Albany, New York (1,2). In 2011, a single genotype of G. destructans was found in bats with geomycosis in different parts of New York (3). The findings raised the possibility of clonal spread of a new pathogen with serious implications for the survival of the affected bat populations (4). To provide information for devising conservation measures, we explored whether this emerging infectious disease is caused by a novel pathogen (5). To do so, we genotyped G. destructans isolates from the midwestern and southern United States. During 2010 and 2011, a total of 11 cultures of G. destructans were isolated and identified: 1 each from Pennsylvania and Ohio, 3 from North Carolina, and 6 from West Virginia (Figure). The cultures came from 8 little brown bats (Myotis lucifugus) and 3 tri-colored bats (Perimyotis subflavus). Two recent G. destructans isolates from New York and 1 G. pannorum isolate were included as controls. Genomic DNA was prepared from fungal growth by the conventional glass bead treatment, phenol–chloroform extraction, and ethanol precipitation. PCR amplifications of 8 G. destructans gene fragments (ALR, Bpntase, DHC1, GPHN, PCS, POB3, SRP72, and VPS13) were performed as described (3). The amplicons were sequenced and nucleotides were aligned by Sequencher 4.8 (www.genecodes.com); phylogenetic analyses were done using PAUP*4.0 software (www.sinauer.com). Figure A) Consensus maximum-parsimony tree of 8 concatenated gene fragments of Geomyces destructans. Data were derived from 13 G. destructans test isolates. G. destructans M1379 and G. pannorum M1378 were used as controls in this study; they were described in ... A total of 4,722 nt sequences were obtained from 8 gene fragments of 13 G. destructans isolates (GenBank accession nos. {"type":"entrez-nucleotide-range","attrs":{"text":"JQ029780-JQ029883","start_term":"JQ029780","end_term":"JQ029883","start_term_id":"380040511","end_term_id":"380040717"}}JQ029780-JQ029883) and 1 G. pannorum isolate (GenBank accession nos. {"type":"entrez-nucleotide","attrs":{"text":"HQ834330","term_id":"386776025","term_text":"HQ834330"}}HQ834330, {"type":"entrez-nucleotide","attrs":{"text":"HQ834347","term_id":"386776059","term_text":"HQ834347"}}HQ834347, {"type":"entrez-nucleotide","attrs":{"text":"HQ834364","term_id":"386776093","term_text":"HQ834364"}}HQ834364, {"type":"entrez-nucleotide","attrs":{"text":"HQ834381","term_id":"386776127","term_text":"HQ834381"}}HQ834381, {"type":"entrez-nucleotide","attrs":{"text":"HQ834398","term_id":"386776161","term_text":"HQ834398"}}HQ834398, {"type":"entrez-nucleotide","attrs":{"text":"HQ834415","term_id":"386776195","term_text":"HQ834415"}}HQ834415, {"type":"entrez-nucleotide","attrs":{"text":"HQ834432","term_id":"386776229","term_text":"HQ834432"}}HQ834432, and {"type":"entrez-nucleotide","attrs":{"text":"HQ834449","term_id":"386776263","term_text":"HQ834449"}}HQ834449). Multiple alignments of these sequences showed 100% identity, and the aligned nucleotides matched perfectly with those of earlier G. destructans sequences for the same gene fragments analyzed from New York isolates (3). The nucleotide alignments of 8 sequences showed differences from those obtained from the closely related fungus, G. pannorum. Maximum-parsimony trees were generated by using sequences from each gene fragment. These trees showed a single clade of G. destructans strains distinct from G. pannorum; similar topologies were obtained when different phylogenetics methods were used for analysis (details not shown). A consensus maximum-parsimony tree derived from the 8 concatenated gene fragments also showed a single clade of G. destructans isolates from New York and the midwestern and southern United States (Figure). The data obtained in this study strongly indicate further clonal spread of G. destructans from its origin near Albany, New York. The locations in which G. destructans was detected in the current study were spread across 5 states, which were >800 miles from Albany. The test isolates were compared with a New York isolate from 2008, which provided a 4-year temporal variation in our sampling. Bats of 2 species were positive for G. desctructans in the current samples, and they yielded the same G. destructans genotype. Thus, there is evidence for host-independent spread of a single clone of G. destructans. These data would support the novel-pathogen hypothesis for the origin of bat geomycosis (5). However, these conclusions are based on limited sampling because isolations of G. destructans from affected bats are uncommon. The demonstration of pure fungal culture in the affected animals is still not the standard for geomycosis diagnostics, and most geomycosis is confirmed by bat morphologic appearance or histopathologic examination. Additionally, our phylogenetics analyses were limited to ≈5 kbp of fungal genomes, which could lead to sampling bias (3). Ideally, a large number of G. destructans isolates, including isolates from Europe, and additional polymorphic markers would be needed to determine the novel or local origin of this pathogen (6,7). The environmental factors that led to introduction or reemergence of G. destructans in mines and caves remain unknown, and their contribution in the spread of the fungus through air, water, and soil is yet to be determined (8). Although no direct evidence has emerged, a role for anthropomorphic activities (occupational or recreational) in this spread is a distinct possibility (9). We provide genetic evidence for further spread of a single genotype of G. destructans from Albany, New York, to locations in the midwestern and southern United States. Experimental transmission of geomycosis from infected bats to healthy bats by direct contact has recently been confirmed (10). Therefore, G. destructans might be rapidly spreading along summer and winter migration routes of bats, which present ample opportunities for mixing of healthy and diseased animals.
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clonal genotype of Geomyces destructans among bats with white nose syndrome new york usa
Emerging Infectious Diseases, 2011Co-Authors: Sunanda S Rajkumar, Sudha Chaturvedi, Robert J Rudd, Joseph C Okoniewski, Vishnu ChaturvediAbstract:The dispersal mechanism of Geomyces destructans, which causes geomycosis (white nose syndrome) in hibernating bats, remains unknown. Multiple gene genealogic analyses were conducted on 16 fungal isolates from diverse sites in New York State during 2008–2010. The results are consistent with the clonal dispersal of a single G. destructans genotype.
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antifungal testing and high throughput screening of compound library against Geomyces destructans the etiologic agent of geomycosis wns in bats
PLOS ONE, 2011Co-Authors: Sudha Chaturvedi, Vishnu Chaturvedi, Sunanda S Rajkumar, Gregory Hurteau, Michael ShtutmanAbstract:Bats in the northeastern U.S. are affected by geomycosis caused by the fungus Geomyces destructans (Gd). This infection is commonly referred to as White Nose Syndrome (WNS). Over a million hibernating bats have died since the fungus was first discovered in 2006 in a cave near Albany, New York. A population viability analysis conducted on little brown bats (Myotis lucifugus), one of six bat species infected with Gd, suggests regional extinction of this species within 20 years. The fungus Gd is a psychrophile ("cold loving"), but nothing is known about how it thrives at low temperatures and what pathogenic attributes allow it to infect bats. This study aimed to determine if currently available antifungal drugs and biocides are effective against Gd. We tested five Gd strains for their susceptibility to antifungal drugs and high-throughput screened (HTS) one representative strain with SpectrumPlus compound library containing 1,920 compounds. The results indicated that Gd is susceptible to a number of antifungal drugs at concentrations similar to the susceptibility range of human pathogenic fungi. Strains of Gd were susceptible to amphotericin B, fluconazole, itraconazole, ketoconazole and voriconazole. In contrast, very high MICs (minimum inhibitory concentrations) of flucytosine and echinocandins were needed for growth inhibition, which were suggestive of fungal resistance to these drugs. Of the 1,920 compounds in the library, a few caused 50%--to greater than 90% inhibition of Gd growth. A number of azole antifungals, a fungicide, and some biocides caused prominent growth inhibition. Our results could provide a theoretical basis for future strategies aimed at the rehabilitation of most affected bat species and for decontamination of Gd in the cave environment.
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editorial what is in a name a proposal to use geomycosis instead of white nose syndrome wns to describe bat infection caused by Geomyces destructans
Mycopathologia, 2011Co-Authors: Vishnu Chaturvedi, Sudha ChaturvediAbstract:In 2006, a mysterious condition was first observed in hibernating bats near Albany, NY, US [1]. The affected animals and carcasses displayed a prominent cotton-like growth around the nostrils, which came to be colloquially termed White Nose Syndrome (WNS). Subsequent studies indicated that the cottony appearance was due to fungal growth. The extensive fungal colonization of bat skin and hair, characteristic histopathological appearance, and exclusive presence of a specific fungal DNA in the animals’ tissues led to the discovery of the causal agent—a newly described species called Geomyces destructans [2–6]. Subsequent studies revealed that this condition has caused the deaths of nearly a million bats in the Northeast and it has rapidly spread to other parts of the country [7]. Unfortunately, the prognosis for bats remains poor at present. The US Fish and Wildlife Service has decided to impose extreme measures, such as barring human access to the caves and the mines where bats live, in an attempt to stop further spread of this disease (http:// www.fws.gov/whitenosesyndrome/pdf/NWRS_WNS_ Guidance_Final1.pdf). Recently, G. destructans growth was reported on bats from many European countries, but the associated morbidity or mortality seen in the US bats was absent from the European animals [8, 9]. Thus, G. destructans causes both colonization and invasive infections in Chiroptera. The underlying mechanisms causing such a wide spectrum of host– pathogen interactions still remain unknown. Bats afflicted with WNS have many symptoms, such as, emaciation, epidermal erosion and ulcers, and extensive wing damage [4, 10]. Accordingly, this disease can be confirmed by the morphological appearance of the fungus on any part of the body, histopathology of affected tissues with demonstration of hyphae–conidia, or demonstration of G. destructans by PCR–nucleotide sequencing [3, 4, 6, 11]. Thus, it is reasonable to conclude that WNS is neither an exclusive presentation nor an all-encompassing description of G. destructans infections in bats. The continued use of this terminology to describe bat disease carries the risk of undue focus on one symptom of what is likely to be a complex host– pathogen interaction. In the fungal kingdom, Geomyces destructans has the closest affinity with Geomyces pannorum, which is widely distributed from the Arctic and the Antarctic to temperate climate zones in cave soil and other substrates [12–15]. The two species can be distinguished by their characteristic conidia and subtle differences in the nucleotide sequences of the ribosomal DNA [5, 16]. Geomyces pannorum is a rare pathogen of humans and animals. It has been V. Chaturvedi (&) S. Chaturvedi Mycology Laboratory, Wadsworth Center, New York State Department of Health and Department of Biomedical Sciences, University at Albany School of Public Health, 120 New Scotland Ave., Albany, NY 12208, USA e-mail: vishnu@wadsworth.org
Gudrun Wibbelt - One of the best experts on this subject based on the ideXlab platform.
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skin lesions in european hibernating bats associated with Geomyces destructans the etiologic agent of white nose syndrome
PLOS ONE, 2013Co-Authors: Gudrun Wibbelt, Sebastien J Puechmaille, Tamas Gorfol, Kristin Muhldorfer, Thijs Bosch, Bernd Ohlendorf, Karsten PassiorAbstract:White-nose syndrome (WNS) has claimed the lives of millions of hibernating insectivorous bats in North America. Its etiologic agent, the psychrophilic fungus Geomyces destructans, causes skin lesions that are the hallmark of the disease. The fungal infection is characterized by a white powdery growth on muzzle, ears and wing membranes. While WNS may threaten some species of North American bats with regional extinction, infection in hibernating bats in Europe seems not to be associated with significant mortality. We performed histopathological investigations on biopsy samples of 11 hibernating European bats, originating from 4 different countries, colonized by G. destructans. One additional bat was euthanized to allow thorough examination of multiple strips of its wing membranes. Molecular analyses of touch imprints, swabs and skin samples confirmed that fungal structures were G. destructans. Additionally, archived field notes on hibernacula monitoring data in the Harz Mountains, Germany, over an 11-year period (2000–2011) revealed multiple capture-recapture events of 8 banded bats repeatedly displaying characteristic fungal colonization. Skin lesions of G. destructans-affected hibernating European bats are intriguingly similar to the epidermal lesions described in North American bats. Nevertheless, deep invasion of fungal hyphae into the dermal connective tissue with resulting ulceration like in North American bats was not observed in the biopsy samples of European bats; all lesions found were restricted to the layers of the epidermis and its adnexae. Two bats had mild epidermal cupping erosions as described for North American bats. The possible mechanisms for any difference in outcomes of G. destructans infection in European and North American bats still need to be elucidated.
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pathophysiology of white nose syndrome in bats a mechanistic model linking wing damage to mortality
Biology Letters, 2013Co-Authors: Lisa Warnecke, David S Blehert, Paul M Cryan, Gudrun Wibbelt, James M Turner, Trent K Bollinger, Vikram Misra, Craig K R WillisAbstract:White-nose syndrome is devastating North American bat populations but we lack basic information on disease mechanisms. Altered blood physiology owing to epidermal invasion by the fungal pathogen Geomyces destructans (Gd) has been hypothesized as a cause of disrupted torpor patterns of affected hibernating bats, leading to mortality. Here, we present data on blood electrolyte concentration, haematology and acid-base balance of hibernating little brown bats, Myotis lucifugus, following experimental inoculation with Gd. Compared with controls, infected bats showed electrolyte depletion (i.e. lower plasma sodium), changes in haematology (i.e. increased haematocrit and decreased glucose) and disrupted acid-base balance (i.e. lower CO2 partial pressure and bicarbonate). These findings indicate hypotonic dehydration, hypovolaemia and metabolic acidosis. We propose a mechanistic model linking tissue damage to altered homeostasis and morbidity/mortality.
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temperature dependent growth of Geomyces destructans the fungus that causes bat white nose syndrome
PLOS ONE, 2012Co-Authors: Michelle L Verant, Justin G Boyles, Gudrun Wibbelt, William Waldrep, David S BlehertAbstract:White-nose syndrome (WNS) is an emergent disease estimated to have killed over five million North American bats. Caused by the psychrophilic fungus Geomyces destructans, WNS specifically affects bats during hibernation. We describe temperature-dependent growth performance and morphology for six independent isolates of G. destructans from North America and Europe. Thermal performance curves for all isolates displayed an intermediate peak with rapid decline in performance above the peak. Optimal temperatures for growth were between 12.5 and 15.8°C, and the upper critical temperature for growth was between 19.0 and 19.8°C. Growth rates varied across isolates, irrespective of geographic origin, and above 12°C all isolates displayed atypical morphology that may have implications for proliferation of the fungus. This study demonstrates that small variations in temperature, consistent with those inherent of bat hibernacula, affect growth performance and physiology of G. destructans, which may influence temperature-dependent progression and severity of WNS in wild bats.
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white nose syndrome is this emerging disease a threat to european bats
Trends in Ecology and Evolution, 2011Co-Authors: Sebastien J Puechmaille, Thomas H Kunz, Gudrun Wibbelt, Winifred F Frick, Paul A Racey, Christian C Voigt, Emma C TeelingAbstract:White-nose syndrome (WNS) is a newly emergent disease that potentially threatens all temperate bat species. A recently identified fungus, Geomyces destructans, is the most likely causative agent of this disease. Until 2009, WNS and G. destructans were exclusively known from North America, but recent studies have confirmed this fungus is also present in Europe. We assembled an international WNS consortium of 67 scientists from 29 countries and identified the most important research and conservation priorities to assess the risk of WNS to European bats. Here, we review what is known about WNS and G. destructans and detail the conservation and research recommendations aimed at understanding and containing this emerging infectious disease.
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pan european distribution of white nose syndrome fungus Geomyces destructans not associated with mass mortality
PLOS ONE, 2011Co-Authors: Sebastien J Puechmaille, Hubert T Fuller, Gudrun Wibbelt, Andreas Kurth, Vanessa Korn, Frederic Forget, Kristin Muhldorfer, Wieslaw Bogdanowicz, Christophe Borel, Thijs BoschAbstract:Background: The dramatic mass mortalities amongst hibernating bats in Northeastern America caused by ‘‘white nosesyndrome’’ (WNS) continue to threaten populations of different bat species. The cold-loving fungus, Geomyces destructans, is the most likely causative agent leading to extensive destruction of the skin, particularly the wing membranes. Recent investigations in Europe confirmed the presence of the fungus G. destructans without associated mass mortality in hibernating bats in six countries but its distribution remains poorly known. Methodology/Principal Findings: We collected data on the presence of bats with white fungal growth in 12 countries in Europe between 2003 and 2010 and conducted morphological and genetic analysis to confirm the identity of the fungus as Geomyces destructans. Our results demonstrate the presence of the fungus in eight countries spanning over 2000 km from West to East and provide compelling photographic evidence for its presence in another four countries including Romania, and Turkey. Furthermore, matching prevalence data of a hibernaculum monitored over two consecutive years with data from across Europe show that the temporal occurrence of the fungus, which first becomes visible around February, peaks in March but can still be seen in some torpid bats in May or June, is strikingly similar throughout Europe. Finally, we isolated and cultured G. destructans from a cave wall adjacent to a bat with fungal growth. Conclusions/Significance: G. destructans is widely found over large areas of the European continent without associated mass mortalities in bats, suggesting that the fungus is native to Europe. The characterisation of the temporal variation in G. destructans growth on bats provides reference data for studying the spatio-temporal dynamic of the fungus. Finally, the presence of G. destructans spores on cave walls suggests that hibernacula could act as passive vectors and/or reservoirs for G. destructans and therefore, might play an important role in the transmission process.
Sebastien J Puechmaille - One of the best experts on this subject based on the ideXlab platform.
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skin lesions in european hibernating bats associated with Geomyces destructans the etiologic agent of white nose syndrome
PLOS ONE, 2013Co-Authors: Gudrun Wibbelt, Sebastien J Puechmaille, Tamas Gorfol, Kristin Muhldorfer, Thijs Bosch, Bernd Ohlendorf, Karsten PassiorAbstract:White-nose syndrome (WNS) has claimed the lives of millions of hibernating insectivorous bats in North America. Its etiologic agent, the psychrophilic fungus Geomyces destructans, causes skin lesions that are the hallmark of the disease. The fungal infection is characterized by a white powdery growth on muzzle, ears and wing membranes. While WNS may threaten some species of North American bats with regional extinction, infection in hibernating bats in Europe seems not to be associated with significant mortality. We performed histopathological investigations on biopsy samples of 11 hibernating European bats, originating from 4 different countries, colonized by G. destructans. One additional bat was euthanized to allow thorough examination of multiple strips of its wing membranes. Molecular analyses of touch imprints, swabs and skin samples confirmed that fungal structures were G. destructans. Additionally, archived field notes on hibernacula monitoring data in the Harz Mountains, Germany, over an 11-year period (2000–2011) revealed multiple capture-recapture events of 8 banded bats repeatedly displaying characteristic fungal colonization. Skin lesions of G. destructans-affected hibernating European bats are intriguingly similar to the epidermal lesions described in North American bats. Nevertheless, deep invasion of fungal hyphae into the dermal connective tissue with resulting ulceration like in North American bats was not observed in the biopsy samples of European bats; all lesions found were restricted to the layers of the epidermis and its adnexae. Two bats had mild epidermal cupping erosions as described for North American bats. The possible mechanisms for any difference in outcomes of G. destructans infection in European and North American bats still need to be elucidated.
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white nose syndrome is this emerging disease a threat to european bats
Trends in Ecology and Evolution, 2011Co-Authors: Sebastien J Puechmaille, Thomas H Kunz, Gudrun Wibbelt, Winifred F Frick, Paul A Racey, Christian C Voigt, Emma C TeelingAbstract:White-nose syndrome (WNS) is a newly emergent disease that potentially threatens all temperate bat species. A recently identified fungus, Geomyces destructans, is the most likely causative agent of this disease. Until 2009, WNS and G. destructans were exclusively known from North America, but recent studies have confirmed this fungus is also present in Europe. We assembled an international WNS consortium of 67 scientists from 29 countries and identified the most important research and conservation priorities to assess the risk of WNS to European bats. Here, we review what is known about WNS and G. destructans and detail the conservation and research recommendations aimed at understanding and containing this emerging infectious disease.
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effect of sample preservation methods on the viability of Geomyces destructans the fungus associated with white nose syndrome in bats
Acta Chiropterologica, 2011Co-Authors: Sebastien J Puechmaille, Hubert T Fuller, Emma C TeelingAbstract:Geomyces destructans is a fungus directly associated with white-nose syndrome (WNS), a recently discovered disease that has caused the death of over one million bats in North America and therefore has prompted intense scientific investigation into its biology. If precautions are not taken, the spread of G. destructans by human transportation for scientific study may be a substantial threat to bat populations. We investigated the viability of G. destructans after being exposed to commonly used DNA/RNA preservation methods. Our first experiment revealed that G. destructans is able to germinate after an eight day storage period in RNAlater or kept dry but could not germinate after storage in 70% or absolute ethanol for the same time period. Storing G. destructans samples at different temperatures did not substantially affect the results. In a second experiment, we showed that G. destructans conidia were only killed after being stored in 70% ethanol for a minimum of 24 hours while only 30 minutes were necessary when stored in absolute ethanol. Our results suggest that the DNA/RNA preservation method has an important impact on the ability of G. destructans to remain viable and should therefore be considered before samples are transported, especially to regions where the fungus has not yet been documented. Our results also strongly advocate the use of high concentrations (i.e., absolute) ethanol over 70% ethanol to rapidly kill G. destructans.
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pan european distribution of white nose syndrome fungus Geomyces destructans not associated with mass mortality
PLOS ONE, 2011Co-Authors: Sebastien J Puechmaille, Hubert T Fuller, Gudrun Wibbelt, Andreas Kurth, Vanessa Korn, Frederic Forget, Kristin Muhldorfer, Wieslaw Bogdanowicz, Christophe Borel, Thijs BoschAbstract:Background: The dramatic mass mortalities amongst hibernating bats in Northeastern America caused by ‘‘white nosesyndrome’’ (WNS) continue to threaten populations of different bat species. The cold-loving fungus, Geomyces destructans, is the most likely causative agent leading to extensive destruction of the skin, particularly the wing membranes. Recent investigations in Europe confirmed the presence of the fungus G. destructans without associated mass mortality in hibernating bats in six countries but its distribution remains poorly known. Methodology/Principal Findings: We collected data on the presence of bats with white fungal growth in 12 countries in Europe between 2003 and 2010 and conducted morphological and genetic analysis to confirm the identity of the fungus as Geomyces destructans. Our results demonstrate the presence of the fungus in eight countries spanning over 2000 km from West to East and provide compelling photographic evidence for its presence in another four countries including Romania, and Turkey. Furthermore, matching prevalence data of a hibernaculum monitored over two consecutive years with data from across Europe show that the temporal occurrence of the fungus, which first becomes visible around February, peaks in March but can still be seen in some torpid bats in May or June, is strikingly similar throughout Europe. Finally, we isolated and cultured G. destructans from a cave wall adjacent to a bat with fungal growth. Conclusions/Significance: G. destructans is widely found over large areas of the European continent without associated mass mortalities in bats, suggesting that the fungus is native to Europe. The characterisation of the temporal variation in G. destructans growth on bats provides reference data for studying the spatio-temporal dynamic of the fungus. Finally, the presence of G. destructans spores on cave walls suggests that hibernacula could act as passive vectors and/or reservoirs for G. destructans and therefore, might play an important role in the transmission process.
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white nose syndrome fungus Geomyces destructans in bat france
Emerging Infectious Diseases, 2010Co-Authors: Sebastien J Puechmaille, Pascal Verdeyroux, Hubert T Fuller, Meriadeg Ar Gouilh, Michael Bekaert, Emma C TeelingAbstract:White-nose syndrome is caused by the fungus Geomyces destructans and is responsible for the deaths of >1,000,000 bats since 2006. This disease and fungus had been restricted to the northeastern United States. We detected this fungus in a bat in France and assessed the implications of this finding.
