Kilburn Vanessa L, Ibáñez Roberto, Green David M
Department of Biology, McGill University, 1205 Docteur Penfield Ave., Montréal, Québec H3A 1B1, Canada.
Dis Aquat Organ. 2011 Dec 6;97(2):127-34. doi: 10.3354/dao02409.
Chytridiomycosis, the disease caused by Batrachochytrium dendrobatidis, is considered to be a disease exclusively of amphibians. However, B. dendrobatidis may also be capable of persisting in the environment, and non-amphibian vectors or hosts may contribute to disease transmission. Reptiles living in close proximity to amphibians and sharing similar ecological traits could serve as vectors or reservoir hosts for B. dendrobatidis, harbouring the organism on their skin without succumbing to disease. We surveyed for the presence of B. dendrobatidis DNA among 211 lizards and 8 snakes at 8 sites at varying elevations in Panama where the syntopic amphibians were at pre-epizootic, epizootic or post-epizootic stages of chytridiomycosis. Detection of B. dendrobatidis DNA was done using qPCR analysis. Evidence of the amphibian pathogen was present at varying intensities in 29 of 79 examined Anolis humilis lizards (32%) and 9 of 101 A. lionotus lizards (9%), and in one individual each of the snakes Pliocercus euryzonus, Imantodes cenchoa, and Nothopsis rugosus. In general, B. dendrobatidis DNA prevalence among reptiles was positively correlated with the infection prevalence among co-occurring anuran amphibians at any particular site (r = 0.88, p = 0.004). These reptiles, therefore, may likely be vectors or reservoir hosts for B. dendrobatidis and could serve as disease transmission agents. Although there is no evidence of B. dendrobatidis disease-induced declines in reptiles, cases of coincidence of reptile and amphibian declines suggest this potentiality. Our study is the first to provide evidence of non-amphibian carriers for B. dendrobatidis in a natural Neotropical environment.
蛙壶菌病是由蛙壶菌引起的疾病，被认为是两栖动物特有的疾病。然而，蛙壶菌也可能在环境中持续存在，非两栖动物载体或宿主可能有助于疾病传播。与两栖动物生活在附近且具有相似生态特征的爬行动物可能作为蛙壶菌的载体或储存宿主，在其皮肤上携带该病原体而不患病。我们在巴拿马不同海拔的8个地点对211只蜥蜴和8条蛇进行了调查，这些地点的同域两栖动物处于蛙壶菌病的流行前、流行期或流行后期。使用定量聚合酶链反应（qPCR）分析检测蛙壶菌DNA。在79只被检查的矮小安乐蜥中有29只（32%）、101只狮色安乐蜥中有9只（9%）以及蛇类中的扁颈斜鳞蛇、中美多斑鞭尾蛇和细纹斜鳞蛇各有1只个体中，不同强度地检测到了蛙壶菌DNA。总体而言，在任何特定地点，爬行动物中蛙壶菌DNA的流行率与同时出现的无尾两栖动物的感染率呈正相关（r = 0.88，p = 0.004）。因此，这些爬行动物可能是蛙壶菌的载体或储存宿主，并可能作为疾病传播媒介。虽然没有证据表明蛙壶菌病导致爬行动物数量下降，但爬行动物和两栖动物数量同时下降的情况表明存在这种可能性。我们的研究首次在新热带自然环境中提供了蛙壶菌非两栖动物携带者的证据。
