Pet dander and difficult-to-control asthma: The burden of illness.

There is evidence that allergy to common indoor pets, particularly cats and dogs, is closely associated with symptomatic asthma in the United States. Because the presence of pets in a home is a potentially modifiable factor, it is important to consider how much asthma morbidity and health care cost might be alleviated by the removal of pets from the homes of all persons with pet-allergic asthma. The percentage of pet-associated excess asthma morbidity was estimated as a proportion of all asthma-related health care costs for the United States.