The sound of a mosquito can mean trouble in many parts of the world.The bite of a mosquito can be deadly.Today, we will hear about some of the diseases these insects carry and what scientists are doing to help protect people.

蚊子的声音在世界的许多地方意味着麻烦。被蚊子叮咬可能是致命的。今天，我们将收听到一些由昆虫携带的疾病，科学家们为了保护人类正对此进行研究。

We begin with one of the most common diseases linked to mosquitoes: malaria.The World Health Organization estimates that almost 630,000 people died from malaria and malaria-related causes in 2012.Most of these cases were in African countries south of the Sahara Desert.

我们首先想到关于蚊子最常见的疾病之一是疟疾。据世界卫生组织估计，2012年近63万人死于疟疾和与疟疾有关的疾病。这些病例大多数发生在撒哈拉南部的非洲国家。

In the United States, scientists are seeking new ways to fight malaria.A group of California researchers is working to develop more effective and less costly ways to protect people from mosquitoes.The researchers work at the University of California Riverside.They are investigating mosquitoes’ sense of smell.They found the insects use the same receptor for identifying carbon dioxide in human breath as they do for the smell of our skin.

在美国，科学家们正寻找新方法来对抗疟疾。加州的一组研究人员正致力于开发更有效和低成本的方式来保护人们免受蚊子的叮咬。研究人员就职于加州大学河滨分校。他们正在研究蚊子的嗅觉。他们发现昆虫使用相同的受体来识别人体呼吸的二氧化碳和皮肤的气味。

Anandasankar Ray is leading the investigation.He says scientists tested more than a million chemical compounds until they found a substance called Ethyl pyruvate.He says Ethyl pyruvate makes the mosquito’s receptor inactive.

Anandasankar Ray是这项调查的主任。他说，科学家测试了一百多万种化合物，直到他们发现了一个名为丙酮酸乙酯的物质。他说，丙酮酸乙酯使蚊子的受体不敏感。

“When we apply Ethyl pyruvate to a human arm and offer it to the mosquitoes -- hungry mosquitoes in a cage -- then very few of the mosquitoes are attracted to the human arm because only a few of them are able to smell it out.”

“当我们把丙酮酸乙酯涂到人的手臂上，并将手臂放在关在笼子里的饥饿的蚊子面前，只有极少数的蚊子被吸引过来，因为只有少数蚊子能闻出来。”

Genevieve Tauxe is a member of the UC Riverside research team.She says it was not easy to find the neurons, or nerve cells, that recognize both the smell of human breath and skin.She describes a device the researchers are using to examine mosquitos.

Genevieve Tauxe是加州大学河滨分校研究团队中的一员。她说，找到既能识别人体呼吸气味又能识别皮肤气味的神经元或神经细胞是很不容易的。她介绍，研究人员正在研究蚊子的器官。

”With this apparatus, we’re able to insert a very small electrode into the part of the mosquito’s nose, effectively, where it’s olfactory neurons are and where the smell is happening.”

“有了这个设备，我们能够将一个非常小的电极有效地插入到蚊子的鼻子内，蚊子的嗅觉神经元在那里，也是在那里可以闻到气味。”

The scientists use these instruments to look for the signals that a mosquito’s neurons send to its brain when it finds an interesting smell.Computer screen images show when the sense is strong or weak.

科学家们使用这些工具来寻找蚊子在发现感兴趣的气味时，神经元向大脑发送的信号。电脑图像显示了这种感觉的强弱。

Anandasankar Ray says a product based on Ethyl pyruvate may cost less to manufacture than DEET, the most effective chemical treatment now in use.He says DEET is too costly for most people who live in areas affected by malaria.

Anandasankar Ray称基于丙酮酸乙酯的一个产品的制造成本可能比避蚊胺更低，避蚊胺是现在使用的最有效的化学方法。他说，对于大多数居住在受疟疾影响的地区，避蚊胺是过于昂贵的。

“Perhaps by finding odors that can attack other target receptors, we will be able to improve upon DEET and finally have the next generation of insect behavior control products.”

“或许通过寻找可以攻击其他目标受体的气味，我们将能够改善避蚊胺，最终生产处新一代的昆虫控制产品。”

The scientists believe they will soon be able to find a way to manufacture less costly and more effective products for the fight against mosquitoes.

科学家们相信他们很快就能找到一种防治蚊虫的更便宜，更有效的方式。

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