Final answer:
Pruritus, or itching of the skin, can be caused by various factors including cercarial dermatitis, infections, and skin diseases like psoriasis.
Step-by-step explanation:
Pruritus is a term used to describe itching of the skin. There are several causes of pruritus in humans:
- Cercarial Dermatitis: Certain species of Schistosoma worms can cause cercarial dermatitis, also known as swimmer's itch or clam digger's itch. It occurs when the cercaria of these worms penetrate human skin, triggering an immune response and causing itchy raised bumps.
- Infection: In some cases, pruritus can be a symptom of an underlying infectious condition. For example, a bacterial infection from a dog bite can lead to itching sensations at the site of the wound.
- Skin Diseases: Skin conditions like psoriasis can also cause pruritus. Psoriasis is a chronic autoimmune disease that results in itchy or sore patches of thick, red skin with silvery scales.