The distribution and host range of the pandemic disease chytridiomycosis in Australia, spanning surveys from 1956 to 2007.

Chytridiomycosis is the worst disease to affect vertebrate biodiversity on record. In Australia, it is thought to have caused the extinction of four frog species, and it threatens the survival of at least 10 more. We report the current distribution and host range of this invasive disease in Australia, which is essential knowledge for conservation management. We envisage that the data be used in a global and national context for predictive modeling, meta-analyses, and risk assessment. Our continent-wide data set comprises 821 sites in Australia and includes 10183 records from more than 80 contributors spanning collection dates from 1956 to 2007. Sick and dead frogs from the field and apparently healthy frogs from museum collections were tested opportunistically for the presence of Batrachochytrium dendrobatidis, the fungal pathogen causing chytridiomycosis, and apparently healthy frogs and tadpoles found during surveys were tested purposively. The diagnostic tests used were histology of skin samples and quantitative PCR of skin swabs. Chytridiomycosis was found in all Australian states and the Australian Capital Territory, but not in the Northern Territory. It appears to be currently confined to the relatively cool and wet areas of Australia, such as along the Great Dividing Range and adjacent coastal areas in the eastern mainland states of Queensland, New South Wales, and Victoria, eastern and central Tasmania, southern South Australia, and southwestern Western Australia. Batrachochytrium dendrobatidis may have been introduced into Australia via the port of Brisbane around 1978 and spread northward and southward. It did not appear to arrive in Western Australia until 1985. The earliest records from South Australia and Tasmania are from 1995 and 2004, respectively, although archival studies from these states are lacking. We also report negative findings showing that the disease does not currently occur in some areas that appear to be environmentally suitable, including Cape York Peninsula in Queensland and most of the World Heritage Area in western Tasmania. Infection with B. dendrobatidis has been recorded from 63 frog species in Australia to date, all belonging to the Hylidae, Limnodynastidae, and Myobatrachidae, with the exception of one individual of a species from the Microhylidae and the introduced cane toad of the family Bufonidae.

壶菌病（Chytridiomycosis）是有记录以来对脊椎动物生物多样性造成最严重破坏的病害。在澳大利亚，该病害被认为已导致4种蛙类灭绝，并威胁到至少另外10种蛙类的生存。本研究报道了这种入侵性病害在澳大利亚的当前分布与宿主范围，这一数据对于物种保护管理而言至关重要。我们期望该数据集可在全球与国家层面被用于预测建模、荟萃分析以及风险评估工作。本次研究的全澳范围数据集涵盖澳大利亚境内821个采样点，包含10183条记录，数据来自80余名贡献者，采集时间跨度为1956年至2007年。研究对野外采集的病亡蛙类以及博物馆馆藏的外观健康蛙类进行了机会性检测，以排查导致壶菌病的真菌病原体蛙壶菌（Batrachochytrium dendrobatidis）；同时对调查过程中发现的外观健康蛙类与蝌蚪进行了针对性检测。本次研究采用的诊断方法包括皮肤样本组织病理学检测以及皮肤拭子定量PCR检测。研究发现壶菌病遍布澳大利亚所有州以及澳大利亚首都领地，但未在北领地检出。目前该病害似乎仅分布于澳大利亚境内气候相对冷凉湿润的区域，例如东部大陆各州昆士兰州、新南威尔士州与维多利亚州的大分水岭（Great Dividing Range）及其邻近沿海区域，塔斯马尼亚州东部与中部区域，南澳大利亚州南部以及西澳大利亚州西南部区域。蛙壶菌可能于1978年前后通过布里斯班港传入澳大利亚，并随后向南北两个方向扩散。该病原体似乎直至1985年才传入西澳大利亚州。南澳大利亚州与塔斯马尼亚州的最早记录分别为1995年与2004年，尽管这两个州目前缺乏相关档案研究数据。本研究同时报道了阴性检测结果：在部分环境条件看似适宜的区域目前并未检出壶菌病，包括昆士兰州的约克角半岛（Cape York Peninsula）以及塔斯马尼亚州西部的大部分世界遗产区域。截至目前，澳大利亚境内已有63种蛙类被检出感染蛙壶菌，其中绝大多数隶属于雨蛙科（Hylidae）、澳蟾科（Limnodynastidae）与龟蟾科（Myobatrachidae），仅存在两个例外：1只姬蛙科（Microhylidae）物种个体以及作为外来物种的海蟾蜍（Bufonidae科）。