What is the primary symptom indicative of scabies?

The primary symptom indicative of scabies is intensely pruritic papules. Scabies is caused by the Sarcoptes scabiei mite, which burrows into the skin and triggers an intense immune response. This leads to severe itching, particularly at night, and the formation of small papules, which can appear on various parts of the body, including the web spaces of fingers, wrists, elbows, and abdomen.

The characteristic itching occurs due to the body's reaction to the mite's feces, eggs, and body parts, creating inflammation and leading to the formation of these itchy papules. This symptom is often the first one noted by patients and is what typically prompts them to seek treatment.

Other symptoms like fever, pustules, and vesicles can occur as secondary complications, often due to scratching leading to bacterial infections, but they are not primary indicators of the condition itself. The hallmark of scabies remains the intensely pruritic papules, setting it apart from other dermatological conditions.