Animal allergens.

Animal allergen exposure in early childhood and its relationship to the development of atopic disease is a subject that has been evolving rapidly. Recently, several well-designed studies have helped elucidate previous, often conflicting findings on this topic. In addition, results from studies on farm-animal exposure have added strength to data on early dog and cat exposure. In this paper, we review several recent studies that have helped clarify the relationship between early animal-allergen exposure and childhood atopic disease.