The third phase, to test whether the vaccine prevents real infection, has not yet been carried out, as there has been no massive spread of H5N1 influenza in people.

第三阶段临床试验用于测试该疫苗是否能够预防真正的传染，由于现在人群中还没有出现大规模的H5N1禽流感传染，所以该阶段还没有实施。

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But he points to growing inequalities in adult mortality -- a "massive spread" between countries with the highest rates and those with the lowest.

VOA: special.2010.05.05

The largest transaction on the fund today was the purchase of a massive call butterfly spread in the December contract.

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Here are two credible threats to global systems: a massive cyber attack that could spread to the rest of world and interfere with SCADA systems everywhere and carbon whiskers that could short out power transmission systems.

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The result was a massive collage that Mr. Warming spread across the wall outside his office.

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