Scientists believe it may be possible to combat malaria¹ by interfering² with the sex lives of the mosquitoes which spread the disease.

科学家相信通过干涉传播疟疾的蚊子的交配过程就可能战胜疟疾。

Anopheles mosquitoes spread malaria

They have shown that the insects can only mate successfully if the male is able to seal his sperm³精液 inside the female using a "mating plug".

Without the plug, fertilisation肥沃，受精 cannot occur, and the animals cannot reproduce.

The Imperial College London study is published in the journal PLoS Biology.

The researchers focused on the species of mosquito primarily主要地，根本上 responsible for the transmission of malaria in Africa - Anopheles gambiae甘比亚虐蚊.

These insects mate only once in their lifetime, so disrupting the reproductive process offers a good way of dramatically reducing their numbers.

When they mate, the male transfers sperm to the female followed by a coagulated凝结 mass of proteins and seminal⁴ fluids精液 known as a mating plug.

This plug is not found in any other species of mosquito and its role had previously⁵ been unclear.

But the Imperial team showed it was essential for ensuring sperm is correctly retained保留，保存 in the female's sperm storage organ, from where she can fertilise eggs over the course of her lifetime.

In the lab, the researchers were able to stop successful reproduction by preventing the formation of the plug in males.

Not a simple barrier

Lead researcher Dr Flaminia Catteruccia said: "We have shown that the male mating plug is not a simple barrier to insemination受精，播种 from rival males, as has been previously suggested.

"Instead, we discovered that the plug plays an important role in allowing the female to successfully store sperm in the correct way inside her, and as such is vital for successful reproduction.

"Removing or interfering with the mating plug renders渲染，放弃 copulation交尾，交配 ineffective.

"This discovery could be used to develop new ways of controlling populations of A. gambiae mosquitoes, to limit the spread of malaria."

The researchers stopped the plug forming by knocking out a key enzyme酶 which causes the seminal fluids to coagulate into a gelatinous胶状的 solid mass.

Another weapon

Dr Catteruccia said: "If in the future we can develop an inhibitor抑制剂 that prevents the coagulating enzyme⁶ doing its job inside male A. gambiae mosquitoes in such a way that can be deployed⁷ easily in the field - for example in the form of a spray水沫，喷雾 as it is done with insecticides - then we could effectively induce sterility⁸不毛，不育 in female mosquitoes in the wild.

"This could provide a new way of limiting the population of this species of mosquito, and could be one more weapon in the arsenal⁹兵工厂，军械库 against malaria."

A team at the International Atomic Energy Agency国际原子能组织 (IAEA) are working on another method to reduce the growth of the mosquito population - using radiation to sterilize消毒，使绝育 male insects.