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Migrating Birds May Spread Flu
Every year, residents of Kunming, Yunnan Province welcome thousands of black headed gulls(红嘴鸥)with food and happy laughter．The lovely white birds fly from Siberia to stay in the Dianchi area of the city in winter．But this year the white angels are no longer lovely in locals eyes, due to their fear of bird flu．
Although scientists have not found the deadly virus in the birds, few people will dare to risk their lives to feed the birds this year．
Across the world, wild migratory birds(候鸟)seem to have become public enemy number one．Since the deadly H5N1 bird flu virus was discovered not only in Asia but also as far away as Europe and Africa, migratory birds were regarded as the carriers．Geographically speaking(从地理上说), the spread of bird flu appears to be following the migratory routes of wild birds．Bird flu is a common disease among wild migratory birds．But the virus may change itself when transferred to fowls and human．
Since the World Health Organization warned last month that migratory birds could carry the deadly H5N1 virus that causes bird flu, many countries, like China, have started tracking migratory birds and cleaning up poultry markets(家禽市场)．China also cancelled(取消)all pigeon races last week．
Scientists said that the migratory routes of wild birds are often far away from big cities．The risk of transferring(传染)the virus directly from wild birds to humans is very low．Scientists also warned that wild birds are shy creatures．They see you coming and fly away at once．But if a wild bird becomes easy to approach, people should be careful that it may be sick．
There are already three areas hit by bird flu in the provinces of Hunan and Anhui and the northern region of Inner Mongolia, areas all on the migratory routes of wild birds．In the past two weeks China has reported three outbreaks of the H5N1 virus that killed 3800 chickens, ducks and geese(鹅)．
