Biology Project Bronchitis Bronchitis is an infection of the larger air passages in the lungs. When bronchitis is in your system it connects to the trachea, and gives you a persisting cough. This makes you cough up phlegm as well as sputum. This infection is acquired in mostly babies, smokers, and the elderly. CAUSES- there are many causes for bronchitis the main one is smoking. Getting a cold or the flu are two more possible ways to get bronchitis. Bronchitis is more common to someone who gets the flu rather than a cold. Viral infections trigger the airways to make it more difficult to breathe. There is two different types of bronchitis: Acute and Chronic, Acute is more of a sudden on set and short duration. This is normally a complication of a viral infection such as a cold or the flu. Words: 142