The gypsy moth is also subject to attack by the nucleopolyhedrosis virus, or wilt disease, a particularly important killer of the caterpillars in outbreak years.

舞毒蛾还会受到核多角体病毒或萎蔫病的攻击，在毛虫爆发的年代，这是一种特别重要的杀手。

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Imagine a killer virus, a bug that mutates so often that it inevitably finds a way to resist every drug.

想像一下，一个病毒杀手，一个变异如此频繁的小生物肯定会产生抵抗一切药物的能力。

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And the large Numbers infected within a short time make pandemics disruptive, even when the virus itself is not an efficient killer.

大部分感染人群在很短时间内会使得流行性疾病发生变异，甚至病毒本身就不是一个有效杀手。

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But we have analysed the potential killer virus against the history of the 2009 Swine Flu and where a drugs cure for a future avian human-to-human killer virus will come far too late.

FORBES: H7N9 Bird Flu Cases Rise To 49, Deaths At 11 In China; Beijing Shuts Poultry Markets

The 1918 pandemic did its worst after the first human death between week 16 and week 26 after the second wave and where the virus had mutated into the deadly human-to-human mass killer.

FORBES: Connect