Poor sanitation and waste disposal practices can lead to various respiratory diseases. When human and animal waste is not properly disposed of, diseases can spread through contaminated water supplies or person-to-person contact. This is a particular problem in areas affected by poverty, as many people living in poverty do not have access to adequate sanitation methods. Respiratory illnesses caused or exacerbated by poor sanitation include asthma, pneumonia, bronchitis, and others. Overall, improper sanitation is associated with about 10% of global disease.