DefinitionBronchitis is inflammation of the main air passages to the lungs. Bronchitis may be short-lived (acute) or chronic, meaning that it lasts a long time and often recurs.See also: Chronic obstructive pulmonary disease (COPD)Alternative NamesInflammation - bronchi; Acute bronchitisCauses, incidence, and risk factorsAcute bronchitis generally follows a viral respiratory infection. At first, it affects your nose, sinuses, and throat and then spreads to the lungs. Sometimes, you may get another (secondary) bacterial infection in the airways.This means that bacteria infect the airways, in addition to the virus.People at risk for acute bronchitis include:The elderly, infants, and young childrenPersons with heart or lung diseaseSmokersChronic bronchitis is a long-term condition. People hav