<unk>  affects extremes of age in certain indigenous populations with a slight female dominance. It is difficult to estimate the prevalence because it is often misdiagnosed. In developed countries, it is important to diagnose the underlying cause and in these countries the age of onset mostly is in adulthood. In developing countries, infection in childhood period is a common cause.
Bronchiectasis epidemiology and demographics
Bronchitis epidemiology and demographics
Bronchiolitis epidemiology and demographics
Chronic bronchitis epidemiology and demographics
Acute bronchitis epidemiology and demographics
Eosinophilic pneumonia epidemiology and demographics
Hypersensitivity pneumonitis epidemiology and demographics
Hemoptysis epidemiology and demographics