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2.
Public Health Nutr ; 26(10): 2165-2179, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37548226

RESUMEN

OBJECTIVE: This review aimed to identify and synthesise the enablers and barriers that influence the long-term (≥ 2 years) sustainment of school-based nutrition programmes. DESIGN: Four databases (PubMed, Cochrane Library, Embase and Scopus) were searched to identify studies reporting on the international literature relating to food and nutrition programmes aimed at school-age (5-14 years) children that had been running for ≥ 2 years (combined intervention and follow-up period). Eligible studies were analysed using the Integrated Sustainability Framework (ISF), which involved deductive coding of programme enablers and barriers. A quality assessment was completed, using the Mixed-Methods Appraisal Tool and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. SETTING: International school-based nutrition programmes. SUBJECTS: Individuals involved with the implementation of school-based nutrition programmes. RESULTS: From the 7366 articles identified, thirteen studies (seven qualitative, five mixed methods and one quantitative descriptive) were included, from which the enablers and barriers of eleven different nutrition-related programmes were analysed. Thirty-four factors across the five domains of the ISF were identified that influenced the sustained implementation of programmes. The most common barrier was a lack of organisational readiness and resources, whereas the most common enabler was having adequate external partnerships and a supportive environment. CONCLUSIONS: These findings have application during the initiation and implementation phases of school-based nutrition programmes. Paying attention to the 'outer contextual factors' of the ISF including the establishment and maintenance of robust relationships across whole of government systems, local institutions and funding bodies are crucial for programme sustainment.


Asunto(s)
Educación en Salud , Instituciones Académicas , Niño , Humanos , Preescolar , Adolescente
3.
Pharm Dev Technol ; 24(9): 1055-1062, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30640552

RESUMEN

Amorphous spray-dried dispersions (SDDs) are a key enabling technology for oral solid dosage formulations, used to improve dissolution behaviour and clinical exposure of poorly soluble active pharmaceutical ingredients (APIs). Appropriate assessment of amorphous dissolution mechanisms is an ongoing challenge. Here we outline the novel application using focused beam reflectance measurement (FBRM) to analyse particle populations orthogonal to USP 2 dissolution. The relative impact of polymer substitution and particle attributes on 25% BMS-708163/HPMC-AS SDD dissolution was assessed. Dissolution mechanisms for SDDs were categorized into erosion versus disintegration. Beyond an initial mixing period, FBRM particle counts diminish slowly and particles are detectable until the point where API dissolution is complete. There is correlation between FBRM particle count decay rate, representing loss of SDD particles in the dissolution media, and UV dissolution rate, measuring dissolved API. For the SDD formulation examined, the degree of succinoyl substitution for HPMC-AS, SDD particle size and surface area all had an impact on dissolution. These data indicate the SDD displayed an erosion mechanism and that FBRM is capturing a rate-limiting step. From this screening tool, the mechanistic understanding and measured impact of polymer chemistry and particle properties can inform a risk-assessment and control strategy for this compound.


Asunto(s)
Excipientes/química , Lactosa/análogos & derivados , Metilcelulosa/análogos & derivados , Oxadiazoles/química , Sulfonamidas/química , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Química Farmacéutica/instrumentación , Diseño de Equipo , Lactosa/química , Metilcelulosa/química , Tamaño de la Partícula , Solubilidad
4.
J Appl Anim Welf Sci ; 22(3): 207-218, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29695170

RESUMEN

Rabbits are commonly kept in a variety of settings, including homes, laboratories, and veterinary clinics. Despite the popularity of keeping this prey species, little research has investigated current methods of handling. The aim of this study was to examine the experience of caregivers (owners and keepers) in using five handling methods commonly referred to in books written for companion animal (pet) owners and veterinary and/or laboratory personnel. An online survey was completed by 2644 respondents, representing all three of these groups, and breeders. Data were acquired to determine sources that participants used to gain knowledge of different handling methods, the methods they used and for what purposes they used them, and their perceptions of any associated difficulties or welfare concerns. Results indicated that participants most frequently used the method of supporting a rabbit's body against a person's chest, which was considered the easiest and most welfare-friendly method of the handling methods explored. "Scruffing with rear support" was the least used method and was considered to be distressing and painful for the rabbit. As rabbits are a terrestrial prey species, being picked up is likely an innately stressful experience. Additional research is encouraged to explore the experience of rabbits during handling to identify methods that can be easily used with the fewest welfare compromises.


Asunto(s)
Crianza de Animales Domésticos/métodos , Bienestar del Animal , Conejos , Adolescente , Adulto , Animales , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Reino Unido
5.
Sci Rep ; 8(1): 7772, 2018 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-29773857

RESUMEN

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.


Asunto(s)
Anfibios/microbiología , Quitridiomicetos/aislamiento & purificación , Especies en Peligro de Extinción , Animales , Difusión de la Información , Larva/microbiología , Programas Informáticos
6.
Science ; 360(6389): 621-627, 2018 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-29748278

RESUMEN

Globalized infectious diseases are causing species declines worldwide, but their source often remains elusive. We used whole-genome sequencing to solve the spatiotemporal origins of the most devastating panzootic to date, caused by the fungus Batrachochytrium dendrobatidis, a proximate driver of global amphibian declines. We traced the source of B. dendrobatidis to the Korean peninsula, where one lineage, BdASIA-1, exhibits the genetic hallmarks of an ancestral population that seeded the panzootic. We date the emergence of this pathogen to the early 20th century, coinciding with the global expansion of commercial trade in amphibians, and we show that intercontinental transmission is ongoing. Our findings point to East Asia as a geographic hotspot for B. dendrobatidis biodiversity and the original source of these lineages that now parasitize amphibians worldwide.


Asunto(s)
Anfibios/microbiología , Extinción Biológica , África , Américas , Animales , Asia , Australia , Quitridiomicetos/clasificación , Quitridiomicetos/genética , Quitridiomicetos/aislamiento & purificación , Quitridiomicetos/patogenicidad , Europa (Continente) , Genes Fúngicos , Variación Genética , Hibridación Genética , Corea (Geográfico) , Filogenia , Análisis de Secuencia de ADN , Virulencia
7.
Nat Commun ; 9(1): 693, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29449565

RESUMEN

Host-associated microbes are vital for combatting infections and maintaining health. In amphibians, certain skin-associated bacteria inhibit the fungal pathogen Batrachochytrium dendrobatidis (Bd), yet our understanding of host microbial ecology and its role in disease outbreaks is limited. We sampled skin-associated bacteria and Bd from Pyrenean midwife toad populations exhibiting enzootic or epizootic disease dynamics. We demonstrate that bacterial communities differ between life stages with few shared taxa, indicative of restructuring at metamorphosis. We detected a significant effect of infection history on metamorph skin microbiota, with reduced bacterial diversity in epizootic populations and differences in community structure and predicted function. Genome sequencing of Bd isolates supports a single introduction to the Pyrenees and reveals no association between pathogen genetics and epidemiological trends. Our findings provide an ecologically relevant insight into the microbial ecology of amphibian skin and highlight the relative importance of host microbiota and pathogen genetics in predicting disease outcome.


Asunto(s)
Antibiosis/fisiología , Anuros/microbiología , Bacterias/clasificación , Quitridiomicetos/patogenicidad , Micosis/prevención & control , Micosis/veterinaria , Piel/microbiología , Animales , Bacterias/aislamiento & purificación , Fenómenos Fisiológicos Bacterianos , Quitridiomicetos/genética , Microbiota/genética , Micosis/microbiología
8.
Parasitology ; 144(4): 484-496, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27873566

RESUMEN

Outbreaks of cutaneous infectious disease in amphibians are increasingly being attributed to an overlooked group of fungal-like pathogens, the Dermocystids. During the last 10 years on the Isle of Rum, Scotland, palmate newts (Lissotriton helveticus) have been reportedly afflicted by unusual skin lesions. Here we present pathological and molecular findings confirming that the pathogen associated with these lesions is a novel organism of the order Dermocystida, and represents the first formally reported, and potentially lethal, case of amphibian Dermocystid infection in the UK. Whilst the gross pathology and the parasite cyst morphology were synonymous to those described in a study from infected L. helveticus in France, we observed a more extreme clinical outcome on Rum involving severe subcutaneous oedema. Phylogenetic topologies supported synonymy between Dermocystid sequences from Rum and France and as well as their distinction from Amphibiocystidium spp. Phylogenetic analysis also suggested that the amphibian-infecting Dermocystids are not monophyletic. We conclude that the L. helveticus-infecting pathogen represents a single, novel species; Amphibiothecum meredithae.


Asunto(s)
Infecciones por Mesomycetozoea/parasitología , Mesomycetozoea/genética , Filogenia , Salamandridae/parasitología , Animales , Islas , Infecciones por Mesomycetozoea/epidemiología , Infecciones por Mesomycetozoea/patología , Escocia/epidemiología
9.
BMC Health Serv Res ; 16: 202, 2016 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-27381448

RESUMEN

BACKGROUND: Suboptimal medication adherence is a significant threat to public health and resources. Devices that organise weekly doses by time and day are commonly used to reduce unintentional non-adherence. However, there is limited evidence to support their use. This systematic review was conducted to evaluate current evidence for their efficacy, safety and costs. METHODS: A pre-defined search of electronic databases from inception to January 2013 augmented with hand-searching was conducted. No limits were placed on publication date. Studies that compared organisation devices used by patients administering their own medication with standard medication packaging regardless of study design were eligible for inclusion. Studies that solely explored dispensing aspects of organisation devices were included whether or not they compared this to standard care. Screening of articles for inclusion and data extraction were completed independently by two reviewers with disagreements resolved by discussion. Outcomes were categorised into impact on health, medication adherence, healthcare utilisation, dispensing errors, supply procedures and costs. Risk of bias was also assessed. RESULTS: Seventeen studies met the inclusion criteria. Health outcomes were investigated in seven studies of which three reported a positive effect associated with organisation devices. Medication adherence was reported in eight studies of which three reported a positive effect. Three studies reported health care utilisation data but overall results are inconclusive. No optimal dispensing or supply procedures were identified. Economic assessment of the impact of organisation devices is lacking. All studies were subject to a high risk of bias. CONCLUSIONS: Evidence regarding the effects of medication organisation devices was limited, and the available evidence was susceptible to a high risk of bias. Organisation devices may help unintentional medication non-adherence and could improve health outcomes. There is a strong need for more studies that explore the impact of such devices on patients, and an equally pressing need for studies that explore the impacts on healthcare services. TRIAL REGISTRATION: This systematic review is registered with PROSPERO (Registration number CRD42011001718 ).


Asunto(s)
Embalaje de Medicamentos , Cumplimiento de la Medicación , Errores de Medicación , Humanos , Errores de Medicación/prevención & control , Farmacias , Calidad de Vida , Sistemas Recordatorios , Resultado del Tratamiento
10.
Ecohealth ; 13(2): 360-7, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27060065

RESUMEN

Batrachochytrium dendrobatidis (Bd) is a pathogenic fungus which causes the disease chytridiomycosis in amphibians by infecting the animals' epidermis. The most commonly applied method for the detection of Bd is the use of a sterile swab, rubbed over the keratinized areas of an amphibian and then processed to yield DNA for detection by qPCR. This method has been used to infer a threshold of lethal infection in some species; however, how reliable and reproducible the swabbing method is at detecting the true burden of infection suffered by individuals is not known. European midwife toads, Alytes obstetricans, are susceptible to chytridiomycosis and are highly parasitised by Bd across Europe. By quantifying Bd-load throughout the entire skin and comparing this to swab results taken from the same individual, we determined whether epidermal swabs provide a quantifiable and accurate indication of the true fungal burden suffered. Further, we examined whether we could infer a threshold for lethal infection based on comparison of swab data taken from infected A. obstetricans exhibiting different clinical states. From swab data, we detected significantly higher fungal burdens from moribund metamorphs compared to visually healthy individuals; however, the ability of these swab data to provide an accurate indication of the true fungal burden was not reliable. These data suggest that fungal load dynamics play an important role in disease-induced mortality in A. obstetricans at these sites, but that using swab data to infer an exact threshold for Bd-associated mortality might be inappropriate and misleading.


Asunto(s)
Anuros/microbiología , Quitridiomicetos/aislamiento & purificación , Micosis/veterinaria , Animales , Europa (Continente) , Manejo de Especímenes
11.
Philos Trans R Soc Lond B Biol Sci ; 371(1709)2016 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-28080980

RESUMEN

Changes in the timings of seasonality as a result of anthropogenic climate change are predicted to occur over the coming decades. While this is expected to have widespread impacts on the dynamics of infectious disease through environmental forcing, empirical data are lacking. Here, we investigated whether seasonality, specifically the timing of spring ice-thaw, affected susceptibility to infection by the emerging pathogenic fungus Batrachochytrium dendrobatidis (Bd) across a montane community of amphibians that are suffering declines and extirpations as a consequence of this infection. We found a robust temporal association between the timing of the spring thaw and Bd infection in two host species, where we show that an early onset of spring forced high prevalences of infection. A third highly susceptible species (the midwife toad, Alytes obstetricans) maintained a high prevalence of infection independent of time of spring thaw. Our data show that perennially overwintering midwife toad larvae may act as a year-round reservoir of infection with variation in time of spring thaw determining the extent to which infection spills over into sympatric species. We used future temperature projections based on global climate models to demonstrate that the timing of spring thaw in this region will advance markedly by the 2050s, indicating that climate change will further force the severity of infection. Our findings on the effect of annual variability on multi-host infection dynamics show that the community-level impact of fungal infectious disease on biodiversity will need to be re-evaluated in the face of climate change.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'.


Asunto(s)
Anuros , Quitridiomicetos/fisiología , Cambio Climático , Reservorios de Enfermedades/veterinaria , Micosis/veterinaria , Animales , Clima , Reservorios de Enfermedades/microbiología , Francia/epidemiología , Lagos/microbiología , Larva/crecimiento & desarrollo , Micosis/epidemiología , Micosis/microbiología , Prevalencia
12.
Sci Rep ; 5: 10828, 2015 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-26022346

RESUMEN

The amphibian parasite Batrachochytrium dendrobatidis (Bd) is regarded as an extreme generalist, infecting over 500 species, but amongst these hosts there exists a great deal of variation in the susceptibility to and the costs of parasite exposure. We use two infection experiments to determine whether inter-specific variation in the sublethal and lethal effects of parasite exposure exist in two host species. We then tested the relative roles of host density and diversity on infection probability of a focal susceptible host. Our results show significant heterogeneity in host species response to parasite exposure, and that both lethal and sub-lethal costs exist in individuals that are able to resist infection, indicating that successful immune response to infection comes at a cost. Further, we show that increasing host density significantly increased the likelihood of susceptible individuals becoming infected with Bd irrespective of host diversity and variation in host susceptibility. These results suggest that populations of resistant species are likely to suffer ill-effects of exposure to Bd regardless of their infection status, and that at the stage of initial infection there was no support for the dilution of transmission events, in contrast to other studies that focus on subsequent transmission of infection.


Asunto(s)
Anuros/parasitología , Quitridiomicetos/patogenicidad , Interacciones Huésped-Parásitos , Animales , Quitridiomicetos/genética , Susceptibilidad a Enfermedades , Especificidad del Huésped/genética , Parásitos/patogenicidad
13.
Ecotoxicology ; 23(7): 1359-65, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24935780

RESUMEN

Amphibians are declining and fertility/fecundity are major drivers of population stability. The development of non-destructive methods to assess reproductive health are needed as destructive measures are fundamentally at odds with conservation goals for declining species. We investigated the utility of body size, nuptial pad size and forelimb width as non-destructive biomarkers of internal reproductive physiology, by analysing correlations with commonly used destructive methods in adult male toads (Bufo bufo) from a low human impact and a high human impact site. Principal component analyses revealed that size was the most important variable for explaining inter-individual differences in other measured endpoints, both non-destructive and destructive, except for hormone levels and nuptial pad, which were independent of size. Toads from the LI and the HI site differed in almost all of the measured endpoints; this was largely driven by the significantly smaller size of toads from the HI site. Correlational analyses within sites revealed that size was correlated with several reproductive endpoints in toads from the HI site but not the LI site, indicating a possible limiting effect of size on reproductive physiology. Intersex was observed in 33% of toads from the HI site and incidence was not related to any other measured endpoint. In conclusion, we provide evidence that size is associated with reproductive physiology and that nuptial pad/hormone levels have potential as additional markers due to their independence from size. We also show that human activities can have a negative effect on reproductive physiology of the common toad.


Asunto(s)
Biomarcadores/análisis , Tamaño Corporal , Bufo bufo/fisiología , Reproducción , Animales , Conservación de los Recursos Naturales , Corticosterona/sangre , Inglaterra , Monitoreo del Ambiente , Fertilidad , Masculino , Testículo/patología , Testosterona/sangre
14.
Conserv Biol ; 28(1): 213-23, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24033675

RESUMEN

Amphibians are globally threatened, but not all species are affected equally by different threatening processes. This is true for the threat posed by the chytridiomycete fungus (Batrachochytrium dendrobatidis). We compiled a European data set for B. dendrobatidis to analyze the trends of infection in European amphibians. The risk of infection was not randomly distributed geographically or taxonomically across Europe. Within countries with different prevalence, infection was nonrandom in certain amphibian taxa. Brown frogs of the genus Rana were unlikely to be infected, whereas frogs in the families Alytidae and Bombinatoridae were significantly more likely to be infected than predicted by chance. Frogs in the 2 families susceptible to B. dendrobatidis should form the core of attempts to develop spatial surveillance studies of chytridiomycosis in Europe. Ideally, surveys for B. dendrobatidis should be augmented by sampling the widespread genus Pelophylax because this taxon exhibits geographically inconsistent overinfection with B. dendrobatidis and surveillance of it may facilitate recognition of factors causing spatial variability of infection intensity. Several European amphibian taxa were not represented in our data set; however, surveillance of unsampled species should also occur when warranted.


Asunto(s)
Anfibios/microbiología , Quitridiomicetos/aislamiento & purificación , Conservación de los Recursos Naturales , Micosis/epidemiología , Animales , Quitridiomicetos/fisiología , Europa (Continente) , Micosis/microbiología , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Medición de Riesgo
15.
Curr Biol ; 24(2): 176-180, 2014 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-24374305

RESUMEN

Research on emerging infectious wildlife diseases has placed particular emphasis on host-derived barriers to infection and disease. This focus neglects important extrinsic determinants of the host/pathogen dynamic, where all barriers to infection should be considered when ascertaining the determinants of infectivity and pathogenicity of wildlife pathogens. Those pathogens with free-living stages, such as fungi causing catastrophic wildlife declines on a global scale, must confront lengthy exposure to environmental barriers before contact with an uninfected host. Hostile environmental conditions therefore have the ability to decrease the density of infectious particles, reducing the force of infection and ameliorating the impact as well as the probability of establishing an infection. Here we show that, in nature, the risk of infection and infectious burden of amphibians infected by the chytrid fungus Batrachochytrium dendrobatidis (Bd) have a significant, site-specific component, and that these correlate with the microfauna present at a site. Experimental infections show that aquatic microfauna can rapidly lower the abundance and density of infectious stages by consuming Bd zoospores, resulting in a significantly reduced probability of infection in anuran tadpoles. Our findings offer new perspectives for explaining the divergent impacts of Bd infection in amphibian assemblages and contribute to our understanding of ecosystem resilience to colonization by novel pathogens.


Asunto(s)
Quitridiomicetos/aislamiento & purificación , Animales , Anuros/microbiología , Micosis , Agua , Microbiología del Agua
16.
PLoS One ; 8(4): e60953, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23646103

RESUMEN

On 9 June 2008, the UK's largest mass stranding event (MSE) of short-beaked common dolphins (Delphinus delphis) occurred in Falmouth Bay, Cornwall. At least 26 dolphins died, and a similar number was refloated/herded back to sea. On necropsy, all dolphins were in good nutritive status with empty stomachs and no evidence of known infectious disease or acute physical injury. Auditory tissues were grossly normal (26/26) but had microscopic haemorrhages (5/5) and mild otitis media (1/5) in the freshest cases. Five lactating adult dolphins, one immature male, and one immature female tested were free of harmful algal toxins and had low chemical pollutant levels. Pathological evidence of mud/seawater inhalation (11/26), local tide cycle, and the relative lack of renal myoglobinuria (26/26) suggested MSE onset on a rising tide between 06:30 and 08∶21 hrs (9 June). Potential causes excluded or considered highly unlikely included infectious disease, gas/fat embolism, boat strike, by-catch, predator attack, foraging unusually close to shore, chemical or algal toxin exposure, abnormal weather/climatic conditions, and high-intensity acoustic inputs from seismic airgun arrays or natural sources (e.g., earthquakes). International naval exercises did occur in close proximity to the MSE with the most intense part of the exercises (including mid-frequency sonars) occurring four days before the MSE and resuming with helicopter exercises on the morning of the MSE. The MSE may therefore have been a "two-stage process" where a group of normally pelagic dolphins entered Falmouth Bay and, after 3-4 days in/around the Bay, a second acoustic/disturbance event occurred causing them to strand en masse. This spatial and temporal association with the MSE, previous associations between naval activities and cetacean MSEs, and an absence of other identifiable factors known to cause cetacean MSEs, indicates naval activity to be the most probable cause of the Falmouth Bay MSE.


Asunto(s)
Conducta Animal , Delfín Común , Animales , Autopsia , Bahías , Causas de Muerte , Femenino , Geografía , Masculino , Factores de Riesgo , Toxicología , Reino Unido
17.
Proc Natl Acad Sci U S A ; 108(46): 18732-6, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22065772

RESUMEN

Batrachochytrium dendrobatidis (Bd) is a globally ubiquitous fungal infection that has emerged to become a primary driver of amphibian biodiversity loss. Despite widespread effort to understand the emergence of this panzootic, the origins of the infection, its patterns of global spread, and principle mode of evolution remain largely unknown. Using comparative population genomics, we discovered three deeply diverged lineages of Bd associated with amphibians. Two of these lineages were found in multiple continents and are associated with known introductions by the amphibian trade. We found that isolates belonging to one clade, the global panzootic lineage (BdGPL) have emerged across at least five continents during the 20th century and are associated with the onset of epizootics in North America, Central America, the Caribbean, Australia, and Europe. The two newly identified divergent lineages, Cape lineage (BdCAPE) and Swiss lineage (BdCH), were found to differ in morphological traits when compared against one another and BdGPL, and we show that BdGPL is hypervirulent. BdGPL uniquely bears the hallmarks of genomic recombination, manifested as extensive intergenomic phylogenetic conflict and patchily distributed heterozygosity. We postulate that contact between previously genetically isolated allopatric populations of Bd may have allowed recombination to occur, resulting in the generation, spread, and invasion of the hypervirulent BdGPL leading to contemporary disease-driven losses in amphibian biodiversity.


Asunto(s)
Anfibios/microbiología , Quitridiomicetos/genética , Quitridiomicetos/fisiología , Virulencia , Animales , Biodiversidad , Linaje de la Célula , Variación Genética , Genotipo , Heterocigoto , Homocigoto , Modelos Genéticos , Filogenia , Polimorfismo de Nucleótido Simple , Proteínas Recombinantes/metabolismo , Recombinación Genética
18.
Ecohealth ; 6(1): 27-32, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19418096

RESUMEN

Batrachochytrium dendrobatidis (Bd), the causative agent of the amphibian disease chytridiomycosis, is an important factor in the global decline of amphibians. Within Europe, animals that exhibit clinical signs of the disease have only been reported in Spain despite the pathogen's wide, but patchy, distribution on the continent. Recently, another occurrence of chytridiomycosis was reported in Euproctus platycephalus, the Sardinian brook newt, on the Mediterranean island of Sardinia, but without any evidence of fatal disease. We report further evidence of the emergence of Bd on Sardinia and the first evidence of lethal chytridiomycosis outside of Spain. Unusual mortalities of the Tyrrhenian painted frog (Discoglossus sardus) were found at three sites in the Limbara mountains of northern Sardinia. Molecular and histological screens of corpses, frogs, and tadpoles from these sites revealed infection with Bd. Infection and mortality occurred at locations that are unusual in terms of the published habitat requirements of the pathogen. Given the endemicity, the IUCN Red List status of the amphibian species on Sardinia, and the occurrence of infection and mortality caused by chytridiomycosis, there is serious reason for concern for the impact that disease emergence may have on the conservation of the amphibians of the island.


Asunto(s)
Anuros/microbiología , Quitridiomicetos/patogenicidad , Enfermedades Transmisibles Emergentes/veterinaria , Micosis/veterinaria , Animales , Enfermedades Transmisibles Emergentes/microbiología , Brotes de Enfermedades/veterinaria , Italia/epidemiología , Micosis/mortalidad
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