In the United States, at least in the short term, "we definitely are 'Plan B' because we will need the emergency use authorization in order to sell our vaccine, " Adams said.

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They will also be ready for human use if the FDA issues an emergency authorization to start distributing swine flu vaccines.

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In 2007, the Justice Department's inspector general found widespread violations in the FBI's use of the letters, including demands without proper authorization and information obtained in non-emergency circumstances.

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