Final answer:
Flea allergic dermatitis (FAD) primarily affects dogs and cats and is a type I hypersensitivity to flea bites. Hypersensitivities can also cause a range of other allergic reactions and autoimmune diseases. Managing allergies often includes avoiding triggers and using treatments such as moisturizers and corticosteroid creams.
Step-by-step explanation:
Flea allergic dermatitis (FAD) is a common condition affecting dogs and cats. It is a hypersensitive reaction to flea bites, particularly to the flea's saliva. This type of hypersensitivity falls under Type I hypersensitivities, which are immediate allergic reactions triggered by the second exposure to an allergen. FAD can cause severe itching, skin damage due to scratching, and secondary skin infections.
Other common forms of hypersensitivity include contact dermatitis, which is a reaction to materials such as latex, and delayed-type hypersensitivity reactions like tuberculin reactions. In the broader context, hypersensitivities can also lead to autoimmune diseases such as diabetes mellitus type I, multiple sclerosis, and rheumatoid arthritis, with various symptoms depending on the condition.
Allergies are caused by an overreaction of the immune system to harmless substances, with eczema being one such allergic reaction that results in itchy, dry skin patches. It's essential for individuals with hypersensitive reactions or allergies to identify and avoid triggers, and to manage symptoms with appropriate treatments like moisturizers, corticosteroid creams, and in some cases, immunosuppressants.