Chickenpox is caused by the varicella-zoster virus. Less than two weeks after exposure, a red itchy rash breaks out on the face, scalp, chest and back and can spread across the entire body. A fever, mild headache, stomachache, and irritability may precede or accompany the rash. The rash begins as spots which turn into blisters that break open and crust over. New spots may continue to appear for several days. This virus is spread through direct contact with the rash or by coughing or sneezing. Chickenpox is highly contagious and quickly spreads through child- care facilities and schools. People who have received the chickenpox vaccine (Varivax) as well as those who have had the disease in the past are usually immune to the virus. Although chickenpox is usually mild, serious cases may occur, especially among newborns and pregnant women. Medications may be prescribed to reduce the likelihood of complications in high-risk individuals. Antivirals such as acyclovir (Zovirax) and varicella-zoster immune globulin (VZIG) may be prescribed for the treatment of chickenpox. Persons with chickenpox should not take aspirin, as this may cause a serious disease known as Reyeâ€™s syndrome. Nonprescription medica- tions such as antihistamines and calamine lotion may help minimize discomfort.