家里撒了蟑螂药，但蟑螂依旧猖狂?最新研究发现，蟑螂对多种杀虫剂产生了交叉耐药性，而且这种耐药性在一代之内提高到之前的6倍。

　　蟑螂对杀虫剂的防御机制正在加强。

　　A new study has found that German cockroaches, the most common species of the insect in the world, are developing cross-resistance to numerous insecticides.

　　最新研究发现，全球最常见的蟑螂种类德国小蠊正对多种杀虫剂产生交叉耐药性。

　　cross-resistance：交互抗性

　　Not only were researchers in some cases unable to reduce cockroach numbers during a six-month study period, even when combining different insecticides, but they found the insects' resistance increased up to six-fold within one generation.

　　在某些情况下，研究人员不仅无法在为期半年的研究期间杀灭部分蟑螂，甚至使用了多种杀虫剂也是如此，而且他们发现，蟑螂的耐药性在一代之内提高到之前的6倍。

　　'This is a previously unrealized challenge in cockroaches,' said Purdue University professor Michael Scharf.

　　普渡大学教授迈克尔·沙夫说：“我们之前在蟑螂身上从未遇到过的挑战。”

　　'Cockroaches developing resistance to multiple classes of insecticides at once will make controlling these pests almost impossible with chemicals alone.'

　　他说：“蟑螂同时对多种杀虫剂产生耐药性将使单纯利用化学物质控制它们变得几乎不可能。”

　　The study published in the journal Scientific Reports focused on the species Blattella germanica L, which can be found all around the world.

　　这项研究发表在《科学报告》杂志上，重点研究了德国小蠊这种遍布全球的蟑螂种类。

　　The team tested different insecticides from different classes, and combinations of the bunch, in multi-unit buildings in Indiana and Illinois over a period of six months.

　　研究小组在半年时间内在印第安纳州和伊利诺伊州的多单元建筑物中测试了不同种类的杀虫剂及其组合。

　　Exterminators often mix insecticides of different classes to ensure they're eliminating bugs that have developed resistance to one, the authors note.

　　研究报告的作者指出，灭虫者通常会混合不同类别的杀虫剂，以确保能够杀灭对某一种杀虫剂产生耐药性的害虫。

　　exterminator [ɪk'stɜːmɪneɪtə]：n.根除者;职业的消灭害虫者

　　Roaches were captured from the sites before the lab to assess the best treatment for each scenario.

　　研究人员从实验室前的多个地点捕捉蟑螂，以评估每种情况下的最佳方案。

　　'If you have the ability to test the roaches first and pick insecticide that has low resistance, that ups the odds,' Scharf said.

　　沙夫说：“如果能先测试蟑螂，然后挑选耐药性弱的杀虫剂，那就增加了杀灭几率。”

　　'But even then, we had trouble controlling populations.'

　　“但是即便如此，我们也很难控制蟑螂的数量。”