VOA慢速英语 通过蚊子传播的疾病

　　The Buzz About Diseases Spread by Mosquitoes

　　通过蚊子传播的疾病

　　VOICE ONE:

　　This is SCIENCE IN THE NEWS in VOA Special English. I'm Shirley Griffith.

　　VOICE TWO:

　　And I'm Steve Ember. Today, we tell about diseases spread by mosquitoes -- the most widely hated insects in the world.

　　(MUSIC)

　　VOICE ONE:

　　There are more than two thousand different kinds of mosquitoes. Female mosquitoes bite people to drink their blood. Male mosquitoes do not drink blood. They drink fluids from plants. The female mosquito uses its thin sucking tube to break the skin, find blood and inject the victim with a substance that keeps blood flowing.

　　The female mosquito drinks the blood and uses it to produce as many as two hundred fifty eggs. The insect leaves the eggs in any standing water.

　　VOICE TWO:

　　The eggs produce worm-like creatures called larvae in two days to a few months. However, some eggs can stay in water for years until conditions are right for development. The larvae feed on organisms in the water. After four to ten days, they change again, into creatures called pupas. The pupas rise to the surface of the water. Adult mosquitoes pull themselves out of the pupas and fly away.

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