scholarly journals Ophidiomycosis surveillance of snakes in Georgia, USA reveals new host species and taxonomic associations with disease

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ellen Haynes ◽  
Houston C. Chandler ◽  
Benjamin S. Stegenga ◽  
Laura Adamovicz ◽  
Emilie Ospina ◽  
...  

Abstract Ophidiomycosis (snake fungal disease) is caused by the fungus Ophidiomyces ophiodiicola and threatens snake health worldwide. It has been documented throughout the eastern United States and severe cases have recently been reported in Georgia, USA. To evaluate disease distribution and prevalence in this state, 786 free-ranging snakes were examined for skin lesions consistent with ophidiomycosis and swabbed to detect O. ophiodiicola DNA using qPCR. Sampled snakes represented 34 species and 4 families; 27.5% had skin lesions, 13.3% were positive for O. ophiodiicola DNA, and 77.8% of the qPCR positive individuals had skin lesions. This is the first report of O. ophiodiicola in five of the 22 species that were qPCR positive. Multinomial logistic regression modeling indicated that Drymarchon couperi had a higher relative risk of apparent ophidiomycosis (lesions present and qPCR positive), and the best models predicting qPCR result and ophidiomycosis category included individual factors and excluded temporal and spatial factors. Phylogeny-based bipartite network analysis showed that Nerodia erythrogaster, Nerodia taxispilota, and D. couperi had the highest prevalence of apparent ophidiomycosis; this category was more prevalent in the subfamily Colubrinae and less prevalent in Natricinae. These results provide important information about ophidiomycosis epidemiology, which has implications for snake conservation.

2020 ◽  
Vol 57 (6) ◽  
pp. 825-837
Author(s):  
Christina M. McKenzie ◽  
Paul T. Oesterle ◽  
Brian Stevens ◽  
Leonard Shirose ◽  
Gabriela F. Mastromonaco ◽  
...  

Ophidiomycosis (snake fungal disease) is caused by the fungus Ophidiomyces ophiodiicola. As ophidiomycosis is difficult to study in free-ranging snakes, a reliable experimental model is needed to investigate transmission, pathogenesis, morbidity, and mortality, and the effects of brumation and temperature on disease development. Our objective was to develop such a model via subcutaneous injection of O. ophiodiicola conidia in red cornsnakes ( Pantherophis guttatus). The model was used to evaluate transmission and the effects of brumation and temperature in co-housed inoculated and noninoculated snakes. All 23 inoculated snakes developed lesions consistent with ophidiomycosis, including heterophilic and granulomatous dermatitis, cellulitis, and myositis, and embolic fungal granulomas throughout the liver and the coelomic connective tissue in 21/23 (91%). In the inoculated snakes, 21% of skin swabs, 37% of exuvia, and all liver samples tested positive by qPCR (quantitative polymerase chain reaction) for O. ophiodiicola. A post brumation skin swab from 1/12 noninoculated snakes that brumated in contact with inoculated snakes tested positive by qPCR, suggesting possible contact transmission. That snake had microscopic skin lesions consistent with ophidiomycosis, but no visible fungal elements. Of the 23 inoculated snakes, 20 (87%) died over the 70-day experiment, with ophidiomycosis considered the primary cause of death; 12 (52%) of the inoculated snakes died during brumation. Overall, this experimental model of ophidiomycosis reproduced skin lesions analogous to those of many natural cases, and internal lesions similar to the most severe natural cases. The study provides tentative experimental evidence for horizontal transmission in brumation, and offers a tool for future studies of this widespread snake disease.


Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1127
Author(s):  
Shanley N. Roach ◽  
Ryan A. Langlois

Astroviruses are non-enveloped, single-stranded RNA viruses that infect mammalian and avian species. In humans, astrovirus infections are one of the most common causes of gastroenteritis in children. Infection has also been linked to serious neurological complications, especially in immunocompromised individuals. More extensive disease has also been characterized in non-human mammalian and avian species. To date, astroviruses have been detected in over 80 different avian and mammalian hosts. As the number of hosts continues to rise, the need to understand how astroviruses transmit within a given species as well as to new host species becomes increasingly important. Here, we review the current understanding of astrovirus transmission, the factors that influence viral spread, and the potential for cross-species transmission. Additionally, we highlight the current gaps in knowledge and areas of future research that will be key to understanding astrovirus transmission and zoonotic potential.


2016 ◽  
Vol 28 (6) ◽  
pp. 709-713 ◽  
Author(s):  
Lisa A. Last ◽  
Heather Fenton ◽  
Jessica Gonyor-McGuire ◽  
Matthew Moore ◽  
Michael J. Yabsley

2021 ◽  
Author(s):  
Erin K. Zess ◽  
Yasin F. Dagdas ◽  
Esme Peers ◽  
Abbas Maqbool ◽  
Mark J. Banfield ◽  
...  

AbstractIn order to infect a new host species, the pathogen must evolve to enhance infection and transmission in the novel environment. Although we often think of evolution as a process of accumulation, it is also a process of loss. Here, we document an example of regressive evolution in the Irish potato famine pathogen (Phytophthora infestans) lineage, providing evidence that a key sequence motif in the effector PexRD54 has degenerated following a host jump. We began by looking at PexRD54 and PexRD54-like sequences from across Phytophthora species. We found that PexRD54 emerged in the common ancestor of Phytophthora clade 1b and 1c species, and further sequence analysis showed that a key functional motif, the C-terminal ATG8-interacting motif (AIM), was also acquired at this point in the lineage. A closer analysis showed that the P. mirabilis PexRD54 (PmPexRD54) AIM appeared unusual, the otherwise-conserved central residue mutated from a glutamate to a lysine. We aimed to determine whether this PmPexRD54 AIM polymorphism represented an adaptation to the Mirabilis jalapa host environment. We began by characterizing the M. jalapa ATG8 family, finding that they have a unique evolutionary history compared to previously characterized ATG8s. Then, using co-immunoprecipitation and isothermal titration calorimetry assays, we showed that both full-length PmPexRD54 and the PmPexRD54 AIM peptide bind very weakly to the M. jalapa ATG8s. Through a combination of binding assays and structural modelling, we showed that the identity of the residue at the position of the PmPexRD54 AIM polymorphism can underpin high-affinity binding to plant ATG8s. Finally, we conclude that the functionality of the PexRD54 AIM was lost in the P. mirabilis lineage, perhaps owing to as-yet-unknown pressure on this effector in the new host environment.Author SummaryPathogens evolve in concert with their hosts. When a pathogen begins to infect a new host species, known as a “host jump,” the pathogen must evolve to enhance infection and transmission. These evolutionary processes can involve both the gain and loss of genes, as well as dynamic changes in protein function. Here, we describe an example of a pathogen protein that lost a key functional domain following a host jump, a salient example of “regressive evolution.” Specifically, we show that an effector protein from the plant pathogen Phytopthora mirabilis, a host-specific lineage closely related to the Irish potato famine pathogen Phytopthora infestans, has a derived amino acid polymorphism that results in a loss of interaction with certain host machinery.


2015 ◽  
Vol 2015 ◽  
pp. 1-4
Author(s):  
Julia Giehr ◽  
Jürgen Heinze ◽  
Alexandra Schrempf

Data on host species and the distribution of the endoparasitic fungusMyrmicinosporidium durumincreased continuously in recent decades. Here, we add the antCardiocondyla elegansas new host species. Colonies of the monogynous species were found infested in the region of Languedoc-Roussillon (South France). Samples from the nest indicate high infection rates. All castes and sexes were infected by the spores. Variations of infection rates between sampling methods and species are discussed.


Animals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3123
Author(s):  
Rebecca Souter ◽  
Anne-Lise Chaber ◽  
Ken Lee ◽  
Aaron Machado ◽  
Jia Lam ◽  
...  

Streptococcus iniae (S. iniae) is a significant aquatic pathogen of farmed fish species, important zoonotic pathogen, and reported cause of disease in captive Amazon River dolphins (Inia geoffrensis) and a bottlenose dolphin (Tursiops truncatus). Here we report S. iniae as the cause of subcutaneous abscesses, sepsis and mortality in a juvenile free-ranging short-beaked common dolphin (Delphinus delphis) found deceased on a metropolitan Australian beach. Body surfaces were covered by multifocal, depressed, deep, irregular cutaneous ulcerations, which microscopically were characterised by ruptured subcutaneous abscesses with intralesional cocci. Routine microbiological investigations revealed a heavy growth of beta-haemolytic Streptococcus sp. identified as Streptococcus iniae in skin lesions as well as from heart blood, the latter supportive of sepsis. Tissues were negative for cetacean morbillivirus and no other disease processes were identified. S. iniae has not been reported in free-ranging marine mammals, nor in Australian delphinids, previously. More notably a pathogen of captive animals, this case report identifies S. iniae as a pathogen of wild dolphins also. In addition to expanding the host reservoir of a significant zoonotic pathogen, determining the source of infection as well as possible consequences for other marine mammals and wild and intensive fish stocks warrants further investigations.


2021 ◽  
Vol 8 ◽  
Author(s):  
Christina M. Davy ◽  
Leonard Shirose ◽  
Doug Campbell ◽  
Rachel Dillon ◽  
Christina McKenzie ◽  
...  

Emerging infectious diseases (EIDs) are typically characterized by novelty (recent detection) and by increasing incidence, distribution, and/or pathogenicity. Ophidiomycosis, also called snake fungal disease, is caused by the fungus Ophidiomyces ophidiicola (formerly “ophiodiicola”). Ophidiomycosis has been characterized as an EID and as a potential threat to populations of Nearctic snakes, sparking over a decade of targeted research. However, the severity of this threat is unclear. We reviewed the available literature to quantify incidence and effects of ophidiomycosis in Nearctic snakes, and to evaluate whether the evidence supports the ongoing characterization of ophidiomycosis as an EID. Data from Canada remain scarce, so we supplemented the literature review with surveys for O. ophidiicola in the Canadian Great Lakes region. Peer-reviewed reports of clinical signs consistent with ophidiomycosis in free-ranging, Nearctic snakes date back to at least 1998, and retrospective molecular testing of samples extend the earliest confirmed record to 1986. Diagnostic criteria varied among publications (n = 33), confounding quantitative comparisons. Ophidiomycosis was diagnosed or suspected in 36/121 captive snakes and was fatal in over half of cases (66.7%). This result may implicate captivity-related stress as a risk factor for mortality from ophidiomycosis, but could also reflect reporting bias (i.e., infections are more likely to be detected in captive snakes, and severe cases are more likely to be reported). In contrast, ophidiomycosis was diagnosed or suspected in 441/2,384 free-ranging snakes, with mortality observed in 43 (9.8 %). Ophidiomycosis was only speculatively linked to population declines, and we found no evidence that the prevalence of the pathogen or disease increased over the past decade of targeted research. Supplemental surveys and molecular (qPCR) testing in Ontario, Canada detected O. ophidiicola on 76 of 657 free-ranging snakes sampled across ~136,000 km2. The pathogen was detected at most sites despite limited and haphazard sampling. No large-scale mortality was observed. Current evidence supports previous suggestions that the pathogen is a widespread, previously unrecognized endemic, rather than a novel pathogen. Ophidiomycosis may not pose an imminent threat to Nearctic snakes, but further research should investigate potential sublethal effects of ophidiomycosis such as altered reproductive success that could impact population growth, and explore whether shifting environmental conditions may alter host susceptibility.


Viruses ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 751
Author(s):  
Rokshana Parvin ◽  
Mohammed Nooruzzaman ◽  
Congriev Kumar Kabiraj ◽  
Jahan Ara Begum ◽  
Emdadul Haque Chowdhury ◽  
...  

Avian influenza virus (AIV) remains a huge challenge for poultry production with negative repercussions for micro- and macro-economy and public health in Bangladesh. High (HP) H5N1 and low pathogenicity (LP) H9N2 AIV are currently endemic in poultry, and both have been reported to infect humans sporadically. Multiple virus introductions of different clades of HPAIV H5N1, reassorted genotypes, and on-going diversification of LPAIV H9N2 create a highly volatile virological environment which potentially implicates increased virulence, adaptation to new host species, and subsequent zoonotic transmission. Allotropy of poultry rearing systems and supply chains further increase the risk of virus spreading, which leads to human exposure and fosters the emergence of new potentially pre-pandemic virus strains. Here, we review the epidemiology, focusing on (i) risk factors for virus spreading, (ii) viral genetic evolution, and (iii) options for AIV control in Bangladesh. It is concluded that improved control strategies would profit from the integration of various intervention tools, including effective vaccination, enhanced biosecurity practice, and improved awareness of producers and traders, although widespread household poultry rearing significantly interferes with any such strategies. Nevertheless, continuous surveillance associated with rapid diagnosis and thorough virus characterization is the basis of such strategies.


2020 ◽  
Author(s):  
Jennifer M. McKenzie ◽  
Steven J. Price ◽  
Grant M. Connette ◽  
Simon J. Bonner ◽  
Jeffrey M. Lorch

Zootaxa ◽  
2018 ◽  
Vol 4479 (1) ◽  
pp. 1 ◽  
Author(s):  
CHARLES S. EISEMAN ◽  
OWEN LONSDALE

We present rearing records of Agromyzidae (Diptera) from five years of collecting throughout the United States. We review host and distribution data, and describe leaf mines, for 93 species, plus 28 others that could not be confidently identified in the absence of male specimens. We report 147 new host species records, including the first rearing records for Agromyza bispinata Spencer, A. diversa Johnson, A. parca Spencer, A. pudica Spencer, A. vockerothi Spencer, Calycomyza michiganensis Steyskal, Ophiomyia congregata (Malloch), and Phytomyza aldrichi Spencer. Phytomyza anemones Hering and (tentatively identified) Cerodontha (Dizygomyza) iraeos (Robineau-Desvoidy) are new to North America; Agromyza albitarsis Meigen, Amauromyza shepherdiae Sehgal, Aulagromyza populicola (Walker), Liriomyza orilliensis Spencer, Phytomyza linnaeae (Griffiths), P. solidaginivora Spencer, and P. solidaginophaga Sehgal are new to the USA. We also present confirmed USA records for Calycomyza menthae Spencer (previous records were based only on leaf mines), Ophiomyia maura (Meigen) (reported from the USA in older literature but deleted from the fauna in the most recent revision (Spencer & Steyskal 1986)), and Phytomyza astotinensis Griffiths and P. thalictrivora Spencer (previously only tentatively recorded from the USA). We provide 111 additional new state records. We describe the following 30 new species: Agromyza fission, A. soka, Melanagromyza palmeri, Ophiomyia euthamiae, O. mimuli, O. parda, Calycomyza artemisivora, C. avira, C. eupatoriphaga, C. vogelmanni, Cerodontha (Dizygomyza) edithae, Cer. (D.) feldmani, Liriomyza ivorcutleri, L. valerianivora, Phytomyza actaeivora, P. aesculi, P. confusa, P. doellingeriae, P. erigeronis, P. hatfieldae, P. hydrophyllivora, P. palmeri, P. palustris, P. sempervirentis, P. tarnwoodensis, P. tigris, P. triangularidis, P. vancouveriella, P. verbenae, and P. ziziae. 


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