Di Rosa Ines, Simoncelli Francesca, Fagotti Anna, Pascolini Rita
Dipartimento di Biologia Cellulare e Ambientale, Università di Perugia, Via Pascoli 1, Perugia 06123, Italy.
Nature. 2007 May 31;447(7144):E4-5; discussion E5-6. doi: 10.1038/nature05941.
Pounds et al. argue that global warming contributes to amphibian declines by encouraging outbreaks of the chytrid fungus Batrachochytrium dendrobatidis. Although our findings agree with the climate-linked epidemic hypothesis, this pathogen is probably not the only proximate factor in such cases: in the Trasimeno Lake area of Umbria in central Italy, for example, the water frog Rana lessonae first declined in the late 1990s, yet chytridiomycosis was not observed until 2003 (refs 5, 6). Here we show that the chytrid was common there throughout 1999-2002, in a previously unknown form that did not cause disease. We therefore think that the focus by Pounds et al. on a single pathogen is hard to justify because the host-parasite ecology is at present so poorly understood.
庞德等人认为，全球变暖通过促使壶菌（蛙壶菌）爆发，导致两栖动物数量减少。虽然我们的研究结果与气候关联的流行病假说相符，但在这类情况中，这种病原体可能并非唯一的直接因素：例如，在意大利中部翁布里亚的特拉西梅诺湖地区，食用蛙于20世纪90年代末首次数量减少，但直到2003年才观察到壶菌病（参考文献5、6）。我们在此表明，在1999年至2002年期间，该壶菌在那里很常见，以一种以前未知的、不会引发疾病的形式存在。因此，我们认为庞德等人将重点放在单一病原体上是难以成立的，因为目前对宿主 - 寄生虫生态学的了解非常有限。
