America's MedImmune has come up with a nasal spray that USES a live flu virus in a weakened form.

美国生物科技公司Medimmune已经生产出鼻腔喷雾剂，运用的是活性流感病毒的弱化形式。

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Sophomore year, the black female students were allowed to live on campus — but it took a flu outbreak, when they cared for their white dormmates, to break down the social barriers, Ms.Logan said.

洛根太太说，大二那年，黑人女生被允许可以住校——但一场流感的爆发才打破了女生间彼此的隔阂，因为她们那时悉心照料她们的白人室友。

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Live birds infected with highly pathogenic avian influenza (HPAI, or bird flu) can infect humans.

如果高致病禽流感(HPAI或禽流感)病毒转移到了人类当中，那么感染该病毒的活禽可引发流感大流行。

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They spiked droplets of human mucus with live flu virus, and then exposed it to air with varying levels of moisture.

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Earlier, the commission slapped a ban on all imports of live birds and untreated feathers from both Turkey and Romania, where bird flu was also detected.

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In addition, people who live with or care for those at high risk for complications from the flu, including healthcare workers, and household visitors of persons at high risk for complications from the flu should be vaccinated.

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