Which condition is often linked with severe itching as a result of parasitic infestation?

Severe itching due to parasitic infestation is most commonly associated with pediculosis, which specifically refers to an infestation by lice. Lice are blood-sucking parasites that inhabit the scalp, body, or pubic region, depending on the type of lice. The scratching caused by the intense itching often results from the body's allergic reaction to the saliva that lice inject during feeding.

In contrast, warts are caused by viral infections (human papillomavirus) and do not normally lead to itching as a primary symptom. Herpes simplex results in painful blisters and lesions rather than itching due to parasitic action. Folliculitis, an inflammation of hair follicles, can cause itching but is primarily related to bacterial or fungal infection rather than a parasitic infestation. Therefore, pediculosis is the condition that distinctly stands out due to its association with severe itching resulting from a parasitic presence.