Chickenpox, also recognized as varicella, is a vastly infectious disease caused by the initial infection with varicella zoster virus. The disease consequences in a characteristic skin rash that forms minute, itchy blisters, which eventually scab over. It typically starts on the face, chest, and back and then spreads to the rest of the body. Other symptoms may comprise fever, feeling tired, and headaches. Symptoms generally last five to ten days.