Chickenpox can cause an itchy blister-like rash on the skin that usually lasts about a week. It can also cause fever, tiredness, loss of appetite and headache. Some people who get chickenpox get a painful rash called shingles, which is also known as herpes zoster, years later.
Chickenpox is usually mild but it can be serious in infants under 12 months of age, adolescents, adults, pregnant women and people with a weakened immune system.
