In areas where the white-nose syndrome fungus has been around for a while, little brown bats seem to have found a way to limit the disease damage.

在白鼻综合症病菌存在了有一段时间的地区，棕色鼠耳蝠似乎找到了限制这个疾病危害的方法。

撰文/播音：杰森·戈尔德曼(Jason G. Goldman)

翻译：郭鑫鹏

审校：丁可含

The little brown bat was once abundant in the eastern U.S. But within the last 15 years, a fungus called Pseudogymnoascus destructans infiltrated a cave in upstate New York. This fungus causes what’s called white-nose syndrome in bats.

棕色鼠耳蝠曾经在美国东部很盛行。但是在近15年中，一个被称作“假裸囊锈腐病菌（Pseudogymnoascus destructans）”的病菌渗入了纽约州北部的洞穴。这个病菌导致了蝙蝠感染白鼻综合症。

The illness has now spread throughout North America, causing widespread bat die-offs. But recently, little brown bats in New York have stopped declining. In fact, their numbers are actually going back up.

白鼻综合症在北美大肆传播，导致大范围的蝙蝠死亡。但是最近，纽约的棕色鼠耳蝠数量的已经不再减少。事实上，它们的数量已经正在回升。

“That was exciting, but we had no idea how these bats were persisting with the disease.” Harvard University epidemiologist Kate Langwig.

“这令人激动，但是我们并不知道这些蝙蝠如何对抗这个疾病。”哈佛大学流行病学家凯特·兰格维。

“Little brown bats, during the fall swarm around hibernacula entrances. During that time period they’re active, and they’re feeding and fattening for winter, they also mate during that time period. Then they go into hibernation, and that’s really when infection peaks. Winter is the time period in which white nose syndrome is happening to bats.”

“棕色鼠耳蝠在秋季会涌入冬眠处入口。在那个时期它们很活跃，它们会为了冬季觅食增重，同一时期进行交配。然后它们进入冬眠场所，这时感染到达峰值。正是冬季，蝙蝠们开始得白鼻综合症。”

To understand how the New York bats were surviving, Langwig and her team compared them to bats from Illinois and Virginia, in colonies that are still experiencing the initial mass die-offs. They wanted to see whether the New York bats had simply found a way to tolerate the presence of the pathogen, or whether they’d actually developed resistance to the infection.

为了明白纽约蝙蝠如何在白鼻综合症中存活下来，兰格维和她的团队将这些蝙蝠与疫情肆虐的伊利诺斯州和维吉尼亚州的蝙蝠进行比较。他们想看纽约蝙蝠是找到了避免染病的方法，还是对该病菌产生了抗体。

“So we found that when bats first return to hibernacula, they still become infected. Both in areas where the fungus has recently invaded as well as in areas where fungus is established, bats become infected at the same time. And then in both places we see the fungus begin to grow and start to increase. However in areas where the disease has been for a number of years, what we find is that the fungus then reaches kind of a plateau.” [Kate E. Langwig et al.., Resistance in persisting bat populations after white-nose syndrome invasion, in Philosophical Transactions of the Royal Society B]

“所以我们发现当蝙蝠首次返回冬眠处，它们依然感染了病菌。在病菌近期才入侵的地区和病菌已经出现了一段时间的地区，蝙蝠同时被感染了。接着我们看到两个地方病菌开始增长和扩散。然而在疾病出现了几年的地区，我们发现病菌接下似乎到达了停滞期。”

So in New York, the disease ramps up starting in the early winter but then the fungus stops spreading. In Illinois and Virginia, it just keeps on growing.

所以在纽约，疾病在初冬时开始出现，但随后病菌停止了扩散。在伊利诺斯州和维吉尼亚州，它还会继续保持增长。

“It suggests that the bats are somehow actually limiting the growth of the fungus on their skin.”

“这表明蝙蝠以某种方式限制了病菌在它们皮肤上的增长。”

Langwig still doesn’t know how the bats are fighting off the disease. She also wants to find out why their resistance doesn’t show up until so late in the winter. Dose the response wait until it hits some threshold? Do the bats’ immune systems just take longer to boot up during hibernation?

兰格维依然不知道蝙蝠是如何对抗这个疾病的。她还想了解为什么蝙蝠的抗体一直到冬季末期才出现。是因为当达到某个阈值才产生反馈？或者是因为蝙蝠的免疫系统在冬眠时需要更长的时间启动？

And last, of course, she wants to know what lessons bat researchers can learn from this population that might help them save other types of bats in other places.

最后，她想知道蝙蝠研究者们可以从这个种群中学到什么，以帮助其他地区的其他蝙蝠种群。

“These results, that little brown bats have developed resistance, are really encouraging to think about. We could see bats abundant once again in the Northeast.”

“棕色鼠耳蝠产生了抗体这个结果，非常值得思考。我们可以看到蝙蝠在东北部的再一次盛行。”

-Jason G. Goldman