Exacerbations of COPD are more commonly seen during the winter season (nearly 1.6 times more frequently). The main cause of these exacerbations is infection with the respiratory virus, rhinovirus. Frequent exacerbations have been shown to lead to a faster decline in the lung function, poorer quality of life and increased mortality. A recent study showed that COPD exacerbations in colder periods of the year take longer to recover from and are more likely to involve cough or coryzal symptoms. The exacerbations in the cold seasons also have a greater impact on daily activity, with patients spending more time indoors and being more likely to be hospitalized with respiratory viral infection.