The first signs of chickenpox are fever, decreased appetite, headache, cough, sore throat and malaise, according to WebMD. Usually these symptoms develop about 14 to 16 days after contact with the virus. Typically, the itchy rash associated with chickenpox appears one or two days after initial symptoms begin.
A person is contagious one to two days before the rash appears, explains WebMD. After the rash appears, it takes one or two days to go through its stages, which include blistering, bursting, drying and crusting over. New groups of blisters develop every day for five to seven days. Usually, it takes about 10 days after the initial symptoms before all blisters have crusted over, at which time the individual can return to day care, school or work.
After a person has had chickenpox, he is not likely to get it again; however, the virus remains dormant in the body, advises the Health Center of Indiana University at Bloomington. In some people, the virus can reactivate and become shingles due to various factors, such as fatigue, stress, illness, certain medications and radiation therapy. Shingles is most common in individuals over the age of 50, but anyone who has had chickenpox is at risk.