Chickenpox, also known as varicella, is a highly contagious viral infection that causes an itchy, blister-like rash that appears on the face, body, neck, arms, and legs. The blisters that form on the skin can break and bleed, triggering a wound healing response at the site. If the wound is severe enough, or if left untreated, it may form into a scar later on. The scars from chickenpox may fade on their own in some cases. However, if you are left with excessive and abnormal scarring, you may need to treat is with clinically-proven scar therapy products.