An Martel

• Ghent University

The chytrid fungus Batrachochytrium salamandrivorans (Bsal) poses a significant threat to amphibian biodiversity, driving severe declines in salamander populations in Europe. While understanding the host–pathogen interaction may yield novel avenues for disease mitigation, effective in vitro models are currently lacking. We here develop a cell-cultu...

Cover Story: Ophidiomycosis, caused by Ophidiomyces ophidiicola (Oo), is an emerging threat to snakes, yet its epidemiology in Europe remains underexplored. We investigated Oo distribution across wild snakes in Italy, integrating both recent field samples and museum specimens. We surveyed 423 snakes of 17 species from 17 regions, detecting Oo in 32...

Ophidiomycosis, caused by the keratinophilic fungus Ophidiomyces ophidiicola (Oo), is an emerging threat to snake populations, yet its epidemiology in Europe remains underexplored. We investigated the distribution of Oo across free-ranging snake populations in Italy, integrating both recent field samples and historical museum specimens. Our survey...

Many species use temperature as a cue to time certain life events. Such phenological events can be particularly sensitive to climate change. In amphibians, seasonal migration events between ponds and winter habitats are crucial to ensure reproduction. Therefore, shifts in phenological events – called phenological shifts – can significantly affect t...

We need urgent conservation efforts to curb global amphibian declines. Individual indicators provide valuable insights into how amphibian populations respond to different management practices. We compared body condition and fluctuating asymmetry of individual alpine newts ( Ichthyosaura alpestris ) from ten populations across a gradient of both ter...

Amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), is associated with declines in ~500 amphibian species globally. Decades after initial disease outbreaks, the trajectory of impacted species varies substantially; while some species continue to decline, there are instances of natural recovery, such as the whistling tree frog, Litoria ver...

Hedgehog (Erinaceus europaeus) declines in western Europe have been associated with the emergence of Hedgehog diphtheric disease (HDD), with a probable multifactorial, yet unidentified etiology. We used metagenomic sequencing of cell-free DNA (cfDNA) in hedgehog blood to identify possible causes of HDD. We detected a novel circovirus species in the...

Recognizing the influence of pathogen diversity on infection dynamics is crucial for mitigating emerging infectious diseases. Characterising such diversity is often complex, for instance when multiple pathogen variants exist that interact differently with the environment and host. Here, we explore genotypic and phenotypic variation of Batrachochytr...

Ticks play a significant role in the transmission of various pathogens, impacting both human and animal health. Understanding the factors influencing tick feeding preferences is crucial for mitigating the risk of tick-borne diseases. This study investigates the blood preference of Ixodes ricinus nymphs, focusing on host species, stress hormone leve...

Aspergillosis causes significant health risks to both birds and mammals. The outcome of these infections is often poor due to delayed diagnosis and treatment failure. We investigated 152 cases of aspergillosis from birds and mammals in Belgium. Most samples originated from the taxonomic orders Artiodactyla (40.1 %) and Columbiformes (19.7 %). Five...

First report of Ophidiomyces ophidiicola in wild barred grass snakes (Natrix helvetica) in the Netherlands Ophidiomyces ophidiicola is the causative agent of ophidiomycosis (also called snake fungal disease) and has been associated with mycosis in individual snakes and population declines in several North American snake species. While cases of ophi...

Ophidiomyces ophidiicola is the causative agent of ophidiomycosis (also called snake fungal disease) and has been associated with mycosis in individual snakes and population declines in several North American snake species. While cases of ophidiomycosis from North America have been numerous in the past two decades, reports from Europe remain sparse...

Simple Summary Campylobacter is the main cause of foodborne human gastroenteritis worldwide. Most of these cases originate from the consumption of poultry products. Broiler chickens are often colonized by this bacterium, with a high prevalence at slaughter age. However, in the first 2–3 weeks of life, chicks are resistant to Campylobacter infection...

The 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 a...

Understanding wildlife responses to novel threats is vital in counteracting biodiversity loss. The emerging pathogen Batrachochytrium salamandrivorans (Bsal) causes dramatic declines in European salamander populations, and is considered an imminent threat to global amphibian biodiversity. However, real-life disease outcomes remain largely uncharact...

Campylobacter is the main cause of human gastroenteritis worldwide, with 50 to 80% of the cases related to consumption of poultry products. Maternal antibodies (MAB) from commercial breeder flocks may protect their progeny against infection during the first few weeks of life. We here studied the prevalence of Campylobacter antibody titers in broile...

Sylvicultural practices are increasingly directed at forest conservation, restoration and sustainable management. Forests with higher structural complexity are expected to be more resilient against climate change impacts and to have a higher diversity of ecological niches. The impact of forest structural complexity on individual organisms, however,...

The sixth mass extinction is a consequence of complex interplay between multiple stressors with negative impact on biodiversity. We here examine the interaction between two globally widespread anthropogenic drivers of amphibian declines: the fungal disease chytridiomycosis and antifungal use in agriculture. Field monitoring of 26 amphibian ponds in...

Hedgehog diphtheric disease (HDD), an ulcerative skin disease with a high fatality rate is an emerging threat to European hedgehogs (Erinaceus europaeus). We explored the potential role of a panel of zoonotic pathogens in the presumed multifactorial nature of HDD in 188 hedgehogs from three wildlife rescue centers in Belgium. As expected, and with...

Amphibians and reptiles are among the vertebrates with greater extinction risk (respectively, 41% and 21% of the species are threatened according to IUCN 2022). Therefore, it is essential to implement strategies to mitigate such extinction risk, through multidisciplinary approaches. This is one of the objectives of the project “AMPHIDEB: Developmen...

The remoteness and isolation of South American tabletop mountain (tepui) summits may protect against infections that underpin global amphibian declines. Increases in recreational pressure in such unspoiled destinations, and in isolated ecosystems globally, pose a poorly understood risk of wildlife disease introduction, especially in supposedly immu...

Despite the microbiome’s key role in health and fitness, little is known about the environmental factors shaping the gut microbiome of wild birds. With habitat fragmentation being recognised as a major threat to biological diversity, we here determined how forest structure influences the bacterial species richness and diversity of wild great tit ne...

Despite devastating effects on global biodiversity, efficient mitigation strategies against amphibian chytridiomycosis are lacking. Since the free-living pathogenic zoospores of Batrachochytrium dendrobatidis (Bd), the infective stage of this disease, can serve as a nutritious food source for components of zooplankton communities, these groups may...

While emerging fungi threaten global biodiversity, the paucity of fungal genome assemblies impedes thoroughly characterizing epidemics and developing effective mitigation strategies. Here, we generate de novo genomic assemblies for six outbreaks of the emerging pathogen Batrachochytrium salamandrivorans ( Bsal ). We reveal the European epidemic cur...

Diverse communities of symbiotic microbes inhabit the digestive systems of vertebrates and play a crucial role in animal health, and host diet plays a major role in shaping the composition and diversity of these communities. Here, we characterized diet and gut microbiome of fire salamander populations from three Belgian forests. We carried out DNA...

The chytrid fungal pathogens Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans cause the skin disease chytridiomycosis in amphibians, which is driving a substantial proportion of an entire vertebrate class to extinction. Mitigation of its impact is largely unsuccessful and requires a thorough understanding of the mechanisms under...

Batrachochytrium dendrobatidis is responsible for amphibian declines worldwide. Decreasing the aquatic density of this chytrid through consumption of its infectious zoospores by Cladocera (water fleas) may mitigate the impact of chytridiomycosis. Understanding this predator-prey relationship requires insights in the zoospore ingestion rate of an av...

Toxin-producing Corynebacterium ulcerans, a causative agent of diphtheria in humans, was isolated from 53 hedgehogs in Belgium during the spring of 2020. Isolates showed low levels of acquired antimicrobial drug resistance. Strain diversity suggests emergence from an endemic situation. These findings stress the need for raising public awareness and...

While the amphibian disease chytridiomycosis is causing ongoing population declines and biodiversity losses around the globe, efficient mitigation strategies are lacking. The free‐living zoospores of the causative agents of this disease, the chytrid pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal), are a po...

Contemporary forest management strives to satisfy contrasting demands on forest ecosystems by promoting multiple ecosystem services. These services are affected in varied manners by alternative management actions operating at local or landscape scales, potentially leading to trade‐offs and synergies that may impede or encourage forest managers to c...

For decades birds of prey have been under the protection of European law, but deliberate or unintentional killing is still a large-scale problem in Europe. In an effort to monitor illegal practices, the Flemish government established several bird of prey hotlines in 2006. Since then, every suspicious death of a bird of prey has been investigated. T...

Ancient enzootic associations between wildlife and their infections allow evolution to innovate mechanisms of pathogenicity that are counterbalanced by host responses. However, erosion of barriers to pathogen dispersal by globalization leads to the infection of hosts that have not evolved effective resistance and the emergence of highly virulent in...

Anthropogenic pressure such as agricultural pollution globally affects amphibian populations. In this study, a total of 178 different compounds from five agrochemical groups (i.e. antimicrobial drugs residues (ADRs), coccidiostats and anthelmintics, heavy metals, mycotoxins and pesticides) were determined monthly, from March until June 2019 in 26 a...

The recent introduction of the chytrid fungus Batrachochytrium salamandrivorans into northeastern Spain threatens salamander diversity on the Iberian Peninsula. We assessed the current epidemiological situation with extensive field sampling of urodele populations. We then sought to delineate priority regions and identify conservation units for the...

EAZA Best Practice Guidelines (Striped) fire salamander, Salamandra salamandra (terrestris) is the first version of the EAZA Best Practice Guidelines for this species. This guideline has evolved out of the growing concern for extinction of local fire salamander populations due to the introduction of the invasive chytrid fungus Batrachochytrium sala...

Gastrointestinal microbiota fulfill pivotal roles in providing a host with nutrition and protection from pathogenic microorganisms. Up to date, most microbiota research has focused on humans and other mammals, whereas birds and especially wild birds lag behind. Within the field of the avian gut microbiome, research is heavily biased towards poultry...

The pandemic disease chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is a major threat to amphibian biodiversity. For most species, the exact mechanisms of chytridiomycosis that lead to negative population dynamics remain uncertain, though mounting evidence suggests that sublethal effects could be an important driver. In...

Starting in 2010, rapid fire salamander (Salamandra salamandra) population declines in northwestern Europe heralded the emergence of Batrachochytrium salamandrivorans (Bsal), a salamander‐pathogenic chytrid fungus. Bsal poses an imminent threat to global salamander diversity owing to its wide host range, high pathogenicity, and long‐term persistenc...

Chytridiomycosis is an emerging infectious disease threatening amphibian populations worldwide. While environmental disinfection is important in mitigating the disease, successful elimination of Batrachochytrium dendrobatidis (Bd) without excessively harming ecosystems is challenging. We selected peracetic acid (PAA) as the most potent of six comme...

Trophic interactions may strongly depend on body size and environmental variation, but this prediction has been seldom tested in nature. Many spiders are generalist predators that use webs to intercept flying prey. The size and mesh of orb webs increases with spider size, allowing a more efficient predation on larger prey. We studied to this extent...

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 pat...

Biodiversity loss affects ecosystem functioning. Top down effects of amphibian declines on the trophic food web of the forest floor are poorly understood. Here we quantify and explain the effects of disease-driven loss of salamanders on the dynamics of forest leaf litter. Using paired mesocosms, within a Belgian forest, we tested the effect of fire...

Communities across trophic levels, and the functional roles they play, are vital for the sustained provision of ecosystem services. In forest systems, diversification of overstorey composition has been shown to be a key driver of biodiversity, but its influence on across‐trophic level relationships remains scarcely known. Species across trophic lev...

While the emerging amphibian disease chytridiomycosis is causing dramatic and ongoing biodiversity losses worldwide, sustainable strategies to mitigate this global threat to amphibians are currently missing. We here propose a conceptual framework for a novel biological mitigation strategy based on the increasing evidence that naturally occurring mi...

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 u...

Wildlife diseases are contributing to the current Earth's sixth mass extinction; one disease, chytridiomycosis, has caused mass amphibian die-offs. While global spread of a hypervirulent lineage of the fungus Batrachochytrium dendrobatidis (BdGPL) causes unprecedented loss of vertebrate diversity by decimating amphibian populations, its impact on a...

Widespread endemism of host-adapted pathogens poses a heavy burden on animal and human health. Mechanisms underpinning long-term host pathogen co-existence and concurrent costs are poorly understood. We use infections in pigeons with pathogenic, pigeon adapted Salmonella Typhimurium to explain how host and pathogen trade-offs and benefits sustain l...

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 pat...

jats:p>The microbiome of wild birds has been associated with health status and risk of disease development, but underlying metabolomic mechanisms are still unknown. Metabolites produced by microbial organisms may affect host metabolic processes and by doing so influence host health. Here we provide for the first time data on the faecal metabolome o...

jats:title>Abstract Emerging infections add to existing threats to the survival of amphibians worldwide. The olm ( Proteus anguinus ) is a vulnerable, troglobiont urodele species with a small European range and restricted to underground karstic systems. Population declines to emerging threats like the chytrid fungus Batrachochytrium salamandrivoran...

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 pathogeni...

The European amphibian fauna is threatened by several different pathogens. We currently know of mortalities linked to ranaviruses (KIK et al. 2011), and to two fungal pathogens, the widespread Batrachochytrium dendrobatidis, causing amphibian mortalities in several European countries (FISHER et al. 2009), and the invasive chytrid fungus B. salamand...

Toxin-producing Corynebacterium ulcerans, causing diphtheria in humans, were isolated from 53 diseased hedgehogs during spring 2020 in Belgium. Isolates showed low levels of acquired antimicrobial resistance. Pronounced strain diversity suggests emergence from an endemic situation. These findings stress the need for raising public awareness and imp...

Trophic interactions may strongly depend on body size and environmental variation, but this prediction has been seldom tested in nature. Many spiders are generalist predators that use webs to intercept flying prey. The size and mesh of orb webs increases with spider size, allowing a more efficient predation on larger prey. We studied to this extent...

Rapid, early, and reliable detection of invasive pathogenic microorganisms is essential in order to either predict or delineate an outbreak, and monitor appropriate mitigation measures. The chytrid fungus Batrachochytrium salamandrivorans is expanding in Europe, and infection with this fungus may cause massive mortality in urodelans (salamanders an...

Lambert et al . question our retrospective and holistic epidemiological assessment of the role of chytridiomycosis in amphibian declines. Their alternative assessment is narrow and provides an incomplete evaluation of evidence. Adopting this approach limits understanding of infectious disease impacts and hampers conservation efforts. We reaffirm th...

A wide range of frogs produce skin poisons composed of bioactive peptides for defence against pathogens, parasites and predators. While several frog families have been thoroughly screened for skin-secreted peptides, others, like the Microhylidae, have remained mostly unexplored. Previous studies of microhylids found no evidence of peptide secretion...

The chytrid fungus Batrachochytrium dendrobatidis has caused the most prominent loss of vertebrate diversity ever recorded, which peaked in the 1980s. Recent incursion by its sister species B. salamandrivorans in Europe raised the alarm for a new wave of declines and extinctions in western Palearctic urodeles. The European Commission has responded...

Oral administration of antibodies is a promising strategy against various infectious diseases. Previously, it was demonstrated that passive immunization by providing hyperimmune egg yolk through the feed reduces Campylobacter jejuni colonization in broilers. Campylobacteriosis is the most commonly reported bacterial foodborne zoonosis worldwide, an...

Real-time quantitative PCR studies largely depend on reference genes for the normalization of gene expression. Stable reference genes should be accurately selected in order to obtain reliable results. We here present a study screening commonly used reference genes (TEF1F, α-centractin, Ctsyn1, GAPDH, R6046, APRT and TUB) in the chytrid fungi Batrac...

Biodiversiteit en het functioneren van ecosystemen Steeds meer plant-en diersoorten gaan achteruit en verdwijnen uit ons landschap. De gevolgen hiervan voor het functioneren van ecosystemen-zoals weerspiegeld in biomassaproductie, bestuiving of koolstofopslag-zijn een 'hot topic' in het ecologisch onderzoek. De voorbije dertig jaar voerden ecologen...

Managing an Amphibian Population in El Montnegre i el Corredor Park to Contain and Eliminate an Outbreak of the Fungus Batrachochytrium salamadrivorans (Bsal) In 2018, the chytrid fungus Batrachochytrium salamandrivorans (Bsal) was detected in a reservoir in El Montnegre i el Corredor Park, resulting in a high mortality rate of the marbled newt (T...

The largest current disease-induced loss of vertebrate biodiversity is due to chytridiomycosis and despite the increasing understanding of the pathogenesis, knowledge unravelling the early host-pathogen interactions remains limited. Batrachochytrium dendrobatidis (Bd) zoospores attach to and invade the amphibian epidermis, with subsequent invasive...

Biodiversity loss is one major outcome of human-mediated ecosystem disturbance. One way that humans have triggered wildlife declines is by transporting disease-causing agents to remote areas of the world. Amphibians have been hit particularly hard by disease due in part to a globally distributed pathogenic chytrid fungus (Batrachochytrium dendrobat...

Biodiversity loss is one major outcome of human-mediated ecosys- tem disturbance. One way that humans have triggered wildlife declines is by transporting disease-causing agents to remote areas of the world. Amphibians have been hit particularly hard by disease due in part to a globally distributed pathogenic chytrid fungus (Batrachochytrium dendrob...

The infectious chytrid fungus Batrachochytrium salamandrivorans ( Bsal ) has been responsible for severe population declines of salamander populations in Europe. Serious population declines and loss of urodelan diversity may occur if appropriate action is not taken to mitigate against the further spread and impact of Bsal . We provide an overview o...

The first requirement of evidence-based conservation is that evidence is available and relevant for decision-makers. We reviewed twenty years of literature on mitigation of amphibian chytridiomycosis to understand whether conservation science is providing relevant and applicable evidence to end-users in this field. Searching the Scopus database wit...

Quantitative real-time polymerase chain reaction is a widely used technique that relies on reference genes for the normalisation of gene expression. These reference genes are constitutively expressed and must remain stable across all samples and treatments. Stability of housekeeping genes may vary and must be optimised for a specific tissue, sample...

Campylobacter jejuni and Campylobacter coli originating from poultry meat have been the most important causes of foodborne bacterial gastroenteritis in the European Union since 2005. In-feed application of maternal antibodies from vaccinated hens was shown to confer protection of broilers against Campylobacter infection. Here, it was investigated i...

Heterogeneity in soil characteristics promotes and maintains coexistence between a diverse set of species. In forests, trees have species-specific impacts on soil abiotic characteristics and mixing of tree species is being promoted as a tool to ensure high levels of diversity and functioning. Yet, limited knowledge is available on the effect of tre...