Emerging infectious diseases such as chytridiomycosis and ranavirus infections are important contributors to the worldwide decline of amphibian populations. We reviewed data on 247 anuran mortality events in 43 States of the United States from 1999–2015. Our findings suggest that a severe infectious disease of tadpoles caused by a protist belonging to the phylum Perkinsea might represent the third most common infectious disease of anurans after ranavirus infections and chytridiomycosis. Severe Perkinsea infections (SPI) were systemic and led to multiorganic failure and death. The SPI mortality events affected numerous anuran species and occurred over a broad geographic area, from boreal to subtropical habitats. Livers from all PCR-tested SPI-tadpoles (n = 19) were positive for the Novel Alveolate Group 01 (NAG01) of Perkinsea, while only 2.5% histologically normal tadpole livers tested positive (2/81), suggesting that subclinical infections are uncommon. Phylogenetic analysis demonstrated that SPI is associated with a phylogenetically distinct clade of NAG01 Perkinsea. These data suggest that this virulent Perkinsea clade is an important pathogen of frogs in the United States. Given its association with mortality events and tendency to be overlooked, the potential role of this emerging pathogen in amphibian declines on a broad geographic scale warrants further investigation.

White-nose syndrome (WNS) caused by the fungus, Pseudogymnoascus destructans ( Pd ) has killed millions of North American hibernating bats. Currently, methods to prevent the disease are limited. We conducted two trials to assess potential WNS vaccine candidates in wild-caught Myotis lucifugus . In a pilot study, we immunized bats with one of four vaccine treatments or phosphate-buffered saline (PBS) as a control and challenged them with Pd upon transfer into hibernation chambers. Bats in one vaccine-treated group, that received raccoon poxviruses (RCN) expressing Pd calnexin (CAL) and serine protease (SP), developed WNS at a lower rate (1/10) than other treatments combined (14/23), although samples sizes were small. The results of a second similar trial provided additional support for this observation. Bats vaccinated orally or by injection with RCN-CAL and RCN-SP survived Pd challenge at a significantly higher rate (P = 0.01) than controls. Using RT-PCR and flow cytometry, combined with fluorescent in situ hybridization, we determined that expression of IFN-γ transcripts and the number of CD4 + T-helper cells transcribing this gene were elevated (P < 0.10) in stimulated lymphocytes from surviving vaccinees (n = 15) compared to controls (n = 3). We conclude that vaccination with virally-vectored Pd antigens induced antifungal immunity that could potentially protect bats against WNS.

BackgroundBrucella ceti infections have been increasingly reported in cetaceans. Brucellosis in these animals is associated with meningoencephalitis, abortion, discospondylitis’, subcutaneous abscesses, endometritis and other pathological conditions B. ceti infections have been frequently described in dolphins from both, the Atlantic and Pacific Oceans. In the Mediterranean Sea, only two reports have been made: one from the Italian Tyrrhenian Sea and the other from the Adriatic Sea.ResultsWe describe the clinical and pathological features of three cases of B. ceti infections in three dolphins stranded in the Mediterranean Catalonian coast. One striped dolphin had neurobrucellosis, showing lethargy, incoordination and lateral swimming due to meningoencephalitis, A B. ceti infected bottlenose dolphin had discospondylitis, and another striped dolphin did not show clinical signs or lesions related to Brucella infection. A detailed characterization of the three B. ceti isolates was performed by bacteriological, molecular, protein and fatty acid analyses.ConclusionsAll the B. ceti strains originating from Mediterranean dolphins cluster together in a distinct phylogenetic clade, close to that formed by B. ceti isolates from dolphins inhabiting the Atlantic Ocean. Our study confirms the severity of pathological signs in stranded dolphins and the relevance of B. ceti as a pathogen in the Mediterranean Sea.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-014-0206-7) contains supplementary material, which is available to authorized users.

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BackgroundNewcastle disease viruses (NDV) are highly contagious and cause disease in both wild birds and poultry. A pigeon-adapted variant of genotype VI NDV, often termed pigeon paramyxovirus 1, is commonly isolated from columbids in the United States and worldwide. Complete genomic characterization of these genotype VI viruses circulating in wild columbids in the United States is limited, and due to the genetic variability of the virus, failure of rapid diagnostic detection has been reported. Therefore, in this study, formalin-fixed paraffin-embedded (FFPE) samples were subjected to next-generation sequencing (NGS) to identify and characterize these circulating viruses, providing valuable genetic information. NGS enables multiple samples to be deep-sequenced in parallel. When used on FFPE samples, this methodology allows for retrospective studies of infectious organisms.MethodsFFPE wild pigeon tissue samples (kidney, liver and spleen) from 10 mortality events in the U.S. between 2010 and 2016 were analyzed using NGS to detect and sequence NDV genomes from randomly amplified total RNA. Results were compared to the previously published immunohistochemistry (IHC) results conducted on the same samples. Additionally, phylogenetic analyses were conducted on the complete and partial fusion gene and complete genome coding sequences.ResultsTwenty-three out of 29 IHC-positive FFPE pigeon samples were identified as positive for NDV by NGS. Positive samples produced an average genome coverage of 99.6% and an average median depth of 199. A previously described sub-genotype (VIa) and a novel sub-genotype (VIn) of NDV were identified as the causative agent of 10 pigeon mortality events in the U.S. from 2010 to 2016. The distribution of these viruses from the North American lineages match the distribution of the Eurasian collared-doves and rock pigeons in the U.S.ConclusionsThis work reports the first successful evolutionary study using deep sequencing of complete NDV genomes from FFPE samples of wild bird origin. There are at least two distinct U.S. lineages of genotype VI NDV maintained in wild pigeons that are continuously evolving independently from each other and have no evident epidemiological connections to viruses circulating abroad. These findings support the hypothesis that columbids are serving as reservoirs of virulent NDV in the U.S.Electronic supplementary materialThe online version of this article (10.1186/s12985-017-0914-2) contains supplementary material, which is available to authorized users.

Meat inspection has the ultimate objective of declaring the meat and offal obtained from carcasses of slaughtered animals fit or unfit for human consumption. This safeguards the health of consumers by ensuring that the food coming from these establishments poses no risk to public health. Concomitantly, it contributes to animal disease surveillance. The Catalan Public Health Protection Agency (Generalitat de Catalunya) identified the need to provide its meat inspectors with a support structure to improve diagnostic capacity: the Slaughterhouse Support Network (SESC). The main goal of the SESC was to offer continuing education to meat inspectors to improve the diagnostic capacity for lesions observed in slaughterhouses. With this aim, a web-based application was designed that allowed meat inspectors to submit their inquiries, images of the lesions, and samples for laboratory analysis. This commentary reviews the cases from the first 6 years of SESC operation (2008-2013). The program not only provides continuing education to inspectors but also contributes to the collection of useful information on animal health and welfare. Therefore, SESC complements animal disease surveillance programs, such as those for tuberculosis, bovine cysticercosis, and porcine trichinellosis, and is a powerful tool for early detection of emerging animal diseases and zoonoses.

Amphibians are one of the most threatened major groups of animals, with decline in amphibian populations often cited as support for the claim that we are witnessing a mass extinction event [1]. The following causes of amphibian decline have been suggested: 1) invasive species causing ecosystem change, 2) overexploitation of natural environments, 3) changes in land use, 4) global environmental change, such as global warming, 5) increased use of pesticides and other polluting chemicals, and 6) the emergence and/or spread of infectious diseases [1-3]. We need to consider all of these factors if we are to understand amphibian decline and plan conservation strategies accordingly. Importantly, infectious-disease-associated decline is cited as a major factor affecting amphibian species categorized as threatened by the International Union for Conservation of Nature (IUCN) Red List (Fig 1). This may be because these species have been studied closelyso disease threats are identified and tracked-or it could be because disease is indeed a key threat for many amphibian groups in decline. However, infectious diseases are difficult to study in amphibians, because the underlying causes of susceptibility to infection are often difficult to pinpoint, the identities of infectious agents or the nature of virulence is unclear, and adequate sampling of populations and the associated disease biogeography is challenging. Recent work has consistently demonstrated that a wide range of protists of the superphylum Alveolata infects the tissues of larval amphibians [4-6]. The alveolates include a diversity of forms (Fig 2A)-for example, Apicomplexa, chrompodellids, Perkinsozoa, dinoflagellates, and Ciliophora (i.e., ciliates). In some cases, a link with disease has been identified, although formal confirmation equivalent to fulfillment of Koch's postulates [7] is lacking. Here, we discuss the diversity and nature of these infectious agents and outline future research questions.

ABSTRACT:In May 2012, an adult, male bottlenose dolphin (Tursiops truncatus) was found stranded and dead on the Spanish Mediterranean coast. At necropsy, several areas of malacia were macroscopically observed in the periventricular parenchyma of the cerebrum. Microscopically a severe, diffuse, pyogranulomatous, and necrotizing meningoencephalomyelitis was associated with numerous intralesional highly pleomorphic fungal structures. After culture, the fungus, Cunninghamella bertholletiae, was identified by culture and PCR. To our knowledge, this is the first reported case of central nervous system mucormycosis due to Cunninghamella bertholletiae in a cetacean.