COPD exacerbation:
COPD symptoms are gradual and worsen over months or years. If symptoms worsen over a short time of days, it is called COPD exacerbation. It includes severe breathlessness, increased amount of cough with sputum, and severe restriction of daily activities. COPD exacerbation results usually from infection including viral and bacterial infections. COPD exacerbation usually needs hospitalization and urgent treatment.