Bronchitis is when the line the bronchial tubes become inflamed. As with the common cold, virtually everyone has had bronchitis at some time. It usually is caused by a viral infection that spreads to the bronchi. There are several types of bronchitis; the most common types are acute and chronic. Acute bronchitis is the inflammation of mucous membranes of the bronchial tubes, it usually only lasts a few days. Chronic bronchitis is when acute bronchitis …showed first 75 words of 664 total…

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