Viruses
Most often, a cold caused by viruses is responsible for acute bronchitis. The cold spreads from the throat deeper into the airways. The exact causative agents may be adeno-, rhino-, corona-, influenza-, and parainfluenza viruses. In children, respiratory-sincytial (RS), ECHO or Coxsackie viruses are possible causes.
Bacteria
Bacteria also often cause bronchitis as a secondary infection (at the same time or after a viral infection). Pathogens include chlamydia and mycoplasma, which multiply inside cells and are therefore difficult for the immune system to fight. The pathogens haemophilus influenzae (meningitis in children) and pneumococci (pneumonia) can also be triggers.
Other diseases
Bronchitis may be the concomitant of other diseases. These include whooping cough, measles, brucellosis, and typhoid fever.
Fungi
Especially in immunocompromised persons (HIV-infected, cancer patients, etc.), fungi such as Candida Albicans (thrush bronchitis) can also trigger acute bronchitis.
Irritants
Vapours, gases, dust and fine dust favour a possible bronchitis. They can also (more rarely) lead to inflammation of the tracheal tree.
Difference to allergic asthma
In bronchitis, the airways are narrowed by inflamed cells and mucus. In contrast, allergic asthma represents an overreaction to certain stimuli, causing the bronchial tubes to suddenly constrict, resulting in an asthma attack.
Favouring factors
- Cigarette smoke
- Cold and damp weather
- Air pollution
- Crowds