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Bacterially Boosted Mosquitoes Could Vex¹ Viruses 蚊子也能抑制病毒传播？

It may sound strange, but scientists are celebrating the survival and spread of tens of thousands of mosquitoes they released in Northeastern Australia. The whole thing makes more sense when you know that these mosquitoes are not just any run-of-the-mill bloodsuckers. They’re weaponized—infected with a type of bacteria that prevents the spread of Zika, dengue and other mosquito-borne viruses.

虽然听起来可能很奇怪，但是科学家们真的在为他们在澳大利亚东北部“放生”的数万只蚊子的幸存和传播而庆祝。若你得知这些蚊子并不仅是普通的吸血动物，那整个事情就说得通了。这些蚊子通过感染一种细菌被武器化。它们感染的细菌能防止寨卡、登革热和其他蚊子传播的病毒进行传播。

The bacterium², called Wolbachia, is present naturally in nearly two-thirds of all insect species, although it’s not usually found in Aedes aegypti, the mosquito responsible for spreading Zika, dengue, yellow fever and chikungunya.

这种细菌名为“沃尔巴克氏菌”，它天然存在于近三分之二的昆虫身上。尽管在埃及伊蚊身上并没有发现这种细菌，但是伊蚊会传播寨卡、登革热、黄热病和基孔肯雅热病毒。

But when researchers introduced Wolbachia into mosquitoes in the lab a decade ago, the bacteria bollixed the skeeters, making them unable to transmit their viruses to humans. Which gives public health experts hope that by releasing big groups of Wolbachia-infected mosquitoes into problem areas, they’ll spread Wolbachia to the local populations—making them incapable³ of transmitting viral diseases to people.   

然而，当十多年前研究人员在实验室里把沃尔巴克氏菌引入蚊子体内时，细菌就对这些蚊子进行了病毒攻击，使它们无法将病毒传播给人类。这给了公共卫生专家希望：通过向问题地区释放大量感染了沃尔巴克氏菌的蚊子，通过它们将沃尔巴克氏菌传播给当地的蚊子，使其无法再将病毒传播给人类。

But a big question was, will the weaponized mosquitoes remain contained where they’re let loose, or will they move enough to mingle⁴ with their wild brethren?

但当时面临的一大问题是，这些武器化的蚊子会在它们被释放的地方留存吗，或者它们的活动足以使它们与野生蚊子混合而生吗？

So researchers in Australia ran a test. In 2013, they released some 35,000 Wolbachia-carrying Aedes aegypti at one site, 131,000 at a second site, and 286,000 at a third site, all in the city of Cairns. And they tracked the insects’ dispersal. Seems the souped-up skeeters spread outward from the two larger introduction areas at a slow but steady rate of about 100 to 200 meters per year. The mosquitoes in the smaller group stayed put. The study is in the journal PLOS Biology.

为此澳大利亚的研究人员进行了一次测试。2013年，他们在凯恩斯市选了三个地点释放携带有沃尔巴克氏菌的埃及伊蚊，第一个地点释放了大约3万5千只，第二个地点释放了13万1千只，第三个地点释放了28万6千只。他们对蚊子的传播情况进行了追踪。结果发现，两个较大的引种区的携菌蚊子以每年约100到200米的速率，缓慢但稳定地向外传播。而最小一组的蚊子则留在原地未动。这项研究发表于《公共科学图书馆·生物学》杂志。

The results indicate that Wolbachia-infected mosquitoes could be effective against viral diseases, if—like bug⁵ spray—they’re applied⁶ liberally over larger areas. In the public health community, that finding may cause a real buzz.

结果表明，如果将它们较大范围地应用，就像杀虫喷雾剂一样，那么感染了沃尔巴克氏菌的蚊子可以有效对抗病毒性疾病。在公共卫生界，这一发现可能会引起一场真正的轰动。