ALBERT

Description: 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, Bd ASIA-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.

Description: The recently emerged chytrid fungus Batrachochytrium salamandrivorans currently causes amphibian population declines. We hypothesized that temperature dictates infection dynamics of B. salamandrivorans, and that therefore heat treatment may be applied to clear animals from infection. We examined the impact of environmental temperature on B. salamandrivorans infection and disease dynamics in fire salamanders (Salamandra salamandra). Colonization of salamanders by B. salamandrivorans occurred at 15°C and 20°C but not at 25°C, with a significantly faster buildup of infection load and associated earlier mortality at 15°C. Exposing B. salamandrivorans infected salamanders to 25°C for 10 days resulted in complete clearance of infection and clinically cured all experimentally infected animals. This treatment protocol was validated in naturally infected wild fire salamanders. In conclusion, we show that B. salamandrivorans infection and disease dynamics are significantly dictated by environmental temperature, and that heat treatment is a viable option for clearing B. salamandrivorans infections. Scientific Reports 5 doi: 10.1038/srep08037

Description: Chytridiomycosis caused by the chytrid fungus Batrachochytrium salamandrivorans (Bsal) poses a serious threat to urodelan diversity worldwide. Antimycotic treatment of this disease using protocols developed for the related fungus Batrachochytrium dendrobatidis (Bd), results in therapeutic failure. Here, we reveal that this therapeutic failure is partly due to different minimum inhibitory concentrations (MICs) of antimycotics against Bsal and Bd. In vitro growth inhibition of Bsal occurs after exposure to voriconazole, polymyxin E, itraconazole and terbinafine but not to florfenicol. Synergistic effects between polymyxin E and voriconazole or itraconazole significantly decreased the combined MICs necessary to inhibit Bsal growth. Topical treatment of infected fire salamanders (Salamandra salamandra), with voriconazole or itraconazole alone (12.5 μg/ml and 0.6 μg/ml respectively) or in combination with polymyxin E (2000 IU/ml) at an ambient temperature of 15 °C during 10 days decreased fungal loads but did not clear Bsal infections. However, topical treatment of Bsal infected animals with a combination of polymyxin E (2000 IU/ml) and voriconazole (12.5 μg/ml) at an ambient temperature of 20 °C resulted in clearance of Bsal infections. This treatment protocol was validated in 12 fire salamanders infected with Bsal during a field outbreak and resulted in clearance of infection in all animals. Scientific Reports 5 doi: 10.1038/srep11788

Description: Emerging infectious diseases are reducing biodiversity on a global scale. Recently, the emergence of the chytrid fungus Batrachochytrium salamandrivorans resulted in rapid declines in populations of European fire salamanders. Here, we screened more than 5000 amphibians from across four continents and combined experimental assessment of pathogenicity with phylogenetic methods to estimate the threat that this infection poses to amphibian diversity. Results show that B. salamandrivorans is restricted to, but highly pathogenic for, salamanders and newts (Urodela). The pathogen likely originated and remained in coexistence with a clade of salamander hosts for millions of years in Asia. As a result of globalization and lack of biosecurity, it has recently been introduced into naive European amphibian populations, where it is currently causing biodiversity loss.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Martel, A -- Blooi, M -- Adriaensen, C -- Van Rooij, P -- Beukema, W -- Fisher, M C -- Farrer, R A -- Schmidt, B R -- Tobler, U -- Goka, K -- Lips, K R -- Muletz, C -- Zamudio, K R -- Bosch, J -- Lotters, S -- Wombwell, E -- Garner, T W J -- Cunningham, A A -- Spitzen-van der Sluijs, A -- Salvidio, S -- Ducatelle, R -- Nishikawa, K -- Nguyen, T T -- Kolby, J E -- Van Bocxlaer, I -- Bossuyt, F -- Pasmans, F -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2014 Oct 31;346(6209):630-1. doi: 10.1126/science.1258268.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. an.martel@ugent.be. ; Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, Antwerp, Belgium. ; Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. ; CIBIO/InBIO, Centro de Investigacao em Biodiversidade e Recursos Geneticos da Universidade do Porto, Instituto de Ciencias Agrarias de Vairao, Rua Padre Armando Quintas, Vairao, Portugal. ; Department of Infectious Disease Epidemiology, Imperial College London, Norfolk Place, London W2 1PG, UK. ; Genome Sequencing and Analysis Program, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. ; Koordinationsstelle fur amphibien- und reptilienschutz in der Schweiz (KARCH), Passage Maximilien-de-Meuron 6, 2000 Neuchatel, Switzerland. Institut fur Evolutionsbiologie und Umweltwissenschaften, Universitat Zurich. Winterthurerstrasse 190, 8057 Zurich, Switzerland. ; Invasive Alien Species Research Team, National Institute for Environment Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan. ; Department of Biology, University of Maryland, College Park, MD 20742, USA. ; Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA. ; Museo Nacional de Ciencias Naturales, Consejo Superior de Investigaciones cientificas (CSIC), Jose Gutierrez Abascal 2, 28006 Madrid, Spain. ; Biogeography Department, Trier University, 54286 Trier, Germany. ; Durrell Institute of Conservation and Ecology, University of Kent, Kent CT2 7NR, UK. Institute of Zoology, Zoological Society of London, London NW1 4RY, UK. ; Institute of Zoology, Zoological Society of London, London NW1 4RY, UK. ; Reptile, Amphibian and Fish Conservation the Netherlands (RAVON), Post Office Box 1413, 6501 BK Nijmegen, Netherlands. ; Department of Earth Science, Environmental and Life (Di.S.T.A.V.), University of Genova, Corso Europa 26, I-16132 Genova, Italy. ; Graduate School of Human and Environmental Studies, Kyoto University, Yoshida Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan. ; Vietnam National Museum of Nature, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam. ; James Cook University, One Health Research Group, School of Public Health, Tropical Medicine and Rehabilitation Sciences, Townsville, Queensland, Australia. ; Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25359973" target="_blank"〉PubMed〈/a〉