Remotely-sensed risk assessments of emerging, invasive pathogens are key to targeted surveillance and outbreak responses. The recent emergence and spread of the fungal pathogen, Batrachochytrium salamandrivorans (Bsal), in Europe has negatively impacted multiple salamander species. Scholars and practitioners are increasingly concerned about the potential consequences of this lethal pathogen in the Americas, where salamander biodiversity is higher than anywhere else in the world.
View Article and Find Full Text PDFAs threats to amphibian health increase, there is a growing need for diagnostic tools to assess and monitor their health status. Plasma protein electrophoresis has proven to be useful in other nonmammalian species. It enables quantification of protein fractions in plasma that may be altered in various disease processes, and is therefore useful in narrowing down differential diagnoses and detecting inflammation, in combination with other modalities such as biochemical and hematologic testing.
View Article and Find Full Text PDFThe world's reptiles and amphibians are experiencing dramatic and ongoing losses in biodiversity, changes that can have substantial effects on ecosystems and human health. In 2022, the first Global Amphibian and Reptile Disease Conference was held, using One Health as a guiding principle. The conference showcased knowledge on numerous reptile and amphibian pathogens from several standpoints, including epidemiology, host immune defenses, wild population effects, and mitigation.
View Article and Find Full Text PDFGlobal trade has been linked with the emergence of novel pathogens and declines in amphibian populations worldwide. The potential for pathogen transmission within and between collections of captive amphibians and spillover to wild populations makes it important to understand the motivations, knowledge, attitudes and behaviors of pet amphibian owners. We surveyed US pet amphibian owners to understand their characteristics and evaluated whether and how they were associated with behavioral intentions to adopt biosecurity practices.
View Article and Find Full Text PDFBatrachochytrium 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.
View Article and Find Full Text PDFWildlife diseases are a major threat for species conservation, and there is a growing need to implement more comprehensive disease response programs to better identify these diseases of concern. During March 2017, we observed moribund and dead eastern newts, Notophthalmus viridescens, in a single pond in middle Tennessee. All moribund individuals were emaciated.
View Article and Find Full Text PDFIntroduction: One of the most important emerging infectious diseases of amphibians is caused by the fungal pathogen . 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 ; however, studies of a similar fungus, , have shown that electrolyte losses and immunosuppression likely play a key role in morbidity and mortality associated with this disease.
View Article and Find Full Text PDFThe emerging fungal amphibian pathogen, (), is currently spreading across Europe and given its estimated invasion potential, has the capacity to decimate salamander populations worldwide. Fungicides are a promising in situ management strategy for due to their ability to treat the environment and infected individuals. However, antifungal drugs or pesticides could adversely affect the environment and non-target hosts, thus identifying safe, effective candidate fungicides for in situ treatment is needed.
View Article and Find Full Text PDFBatrachochytrium salamandrivorans is an emerging fungus that is causing salamander declines in Europe. We evaluated whether an invasive frog species (Cuban treefrog, Osteopilus septentrionalis) that is found in international trade could be an asymptomatic carrier when exposed to zoospore doses known to infect salamanders. We discovered that Cuban treefrogs could be infected with B.
View Article and Find Full Text PDFTransmission is the fundamental process whereby pathogens infect their hosts and spread through populations, and can be characterized using mathematical functions. The functional form of transmission for emerging pathogens can determine pathogen impacts on host populations and can inform the efficacy of disease management strategies. By directly measuring transmission between infected and susceptible adult eastern newts (Notophthalmus viridescens) in aquatic mesocosms, we identified the most plausible transmission function for the emerging amphibian fungal pathogen Batrachochytrium salamandrivorans (Bsal).
View Article and Find Full Text PDFEnvironmental 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.
View Article and Find Full Text PDFPopulations of the eastern hellbender Cryptobranchus alleganiensis alleganiensis have been declining for decades, and emerging pathogens and pesticides are hypothesized to be contributing factors. However, few empirical studies have attempted to test the potential effects of these factors on hellbenders. We simultaneously exposed subadult hellbenders to environmentally relevant concentrations of either Batrachochytrium dendrobatidis (Bd) or a frog virus 3-like ranavirus (RV), a combination of the pathogens, or each pathogen following exposure to a glyphosate herbicide (Roundup).
View Article and Find Full Text PDFControlled experiments are one approach to understanding the pathogenicity of etiologic agents to susceptible hosts. The recently discovered fungal pathogen, Batrachochytrium salamandrivorans (Bsal), has resulted in a surge of experimental investigations because of its potential to impact global salamander biodiversity. However, variation in experimental methodologies could thwart knowledge advancement by introducing confounding factors that make comparisons difficult among studies.
View Article and Find Full Text PDFDiscovered in 2013, the chytrid fungus Batrachochytrium salamandrivorans (Bsal) is an emerging amphibian pathogen that causes ulcerative skin lesions and multifocal erosion. A closely related pathogen, B. dendrobatidis (Bd), has devastated amphibian populations worldwide, suggesting that Bsal poses a significant threat to global salamander biodiversity.
View Article and Find Full Text PDFBatrachochytrium salamandrivorans (Bsal) is an emerging invasive pathogen that is highly pathogenic to salamander species. Modeling infection dynamics in this system can facilitate proactive efforts to mitigate this pathogen's impact on North American species. Given its widespread distribution and high abundance, the eastern newt (Notophthalmus viridescens) has the potential to significantly influence Bsal epidemiology.
View Article and Find Full Text PDFAn amendment to this paper has been published and can be accessed via a link at the top of the paper.
View Article and Find Full Text PDFRanaviruses are important emerging pathogens of ectothermic vertebrates that threaten aquaculture and wildlife worldwide. A mortality event occurred in a cultured population of catfish-like loach (Triplophysa siluorides) in Sichuan Province, China. Gross clinical signs of the affected fish included skin lesions and haemorrhagic ulcers, which are often associated with ranaviruses.
View Article and Find Full Text PDFand are important amphibian pathogens responsible for morbidity and mortality in free-ranging and captive frogs, salamanders, and caecilians. While has a widespread global distribution, 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.
View Article and Find Full Text PDFPurpose: We report three cases of lens dislocation due to ocular trauma from a recoiling exercise band.
Observations: Three patients had closed globe injury resulting in lens dislocation. All had previously undergone intraocular surgeries; two patients were within three weeks of pars plana vitrectomy for retinal detachment repair.
Objectives: In non-small cell lung cancer (NSCLC) patients, to establish whether the fractional volumes of irradiated anatomic or perfused lung differed between those with and without deteriorating lung function or radiation associated lung injury (RALI).
Methods: 48 patients undergoing radical radiotherapy for NSCLC had a radiotherapy-planning CT scan and single photon emission CT lung perfusion imaging (Tc-labelled macroaggregate albumin). CT defined the anatomic and the single photon emission CT scan (co-registered with CT) identified the perfused (threshold 20 % of maximum) lung volumes.
Ranaviruses have been identified as the cause of explosive disease outbreaks in amphibians worldwide and can be transmitted between hosts both via direct and indirect contact, in which humans might contribute to the translocation of contaminated material. The aim of this study was to evaluate the possible role of water sports in the human translocation of ranavirus, Batrachochytrium dendrobatidis (Bd), and B. salamandrivorans (Bsal).
View Article and Find Full Text PDFUnderstanding the distribution of pathogens across landscapes and their prevalence within host populations is a common aim of wildlife managers. Despite the need for unbiased estimates of pathogen occurrence and prevalence for planning effective management interventions, many researchers fail to account for imperfect pathogen detection. Instead raw data are often reported, which may lead to ineffective, or even detrimental, management actions.
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