Fluenz is a live attenuated - weakened - intranasal vaccine, which has been used for several years in the United States under the brand name FluMist.

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Things that can predispose to chronic bacterial infection include allergies, oral infections, an anatomic blockage such as a deviated nasal septum, nasal polyps or enlarged tonsils, frequent swimming, intranasal cocaine use, immunodeficiency syndromes and diseases such as cystic fibrosis and diabetes.

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