What are the first symptoms of scabies? what is the very first signs and symptoms that define a rash as a scabies rash?

Itching!!: You may have a rash that looks a bit like pimples accompanied by intense itching. It is miserable!

Itch: Scabies tend to create burrows and small red bumps in the skin, often found in underarms, belly button and inter digit web spaces. In infants, buttocks are commonly involved. Your doctor can diagnose this by finding scabies mite on skin scraping. They typically don't affect the face or scalp, so treatment is usually topical Elimite (permethrin) applied to every inch of your skin from neck down.

Itching.: The essential lesion is a small, erythematous papule, often excoriated and tipped with hemorrhagic crusts. It is not a dramatic lesion and not always easy to see. The burrow is most specific, a thin, grayish, reddish, or brownish line that is 2 to 15 mm long. The sides and webs of fingers, wrist folds, outer elbows, groin, buttocks, and feet are common areas of involvement.