For more information, see the Chickenpox vaccine information statement.
The varicella vaccine helps protect against chickenpox (varicella), a very contagious infection caused by the varicella-zoster virus. It causes an itchy rash that looks like small blisters with a red base. In some people, the brain, lungs, and heart can become infected, resulting in serious illness or death. The virus remains in the body after the illness has resolved. If it is reactivated, it can cause shingles years later.
Vaccination against varicella is part of the routine vaccination schedule recommended for children. The vaccine is given as an injection under the skin. Two doses are given: at age 12 to 15 months and at age 4 to 6 years. It is also recommended for all adolescents and adults who have not had the vaccine or the disease. It is given to them in two doses 4 to 12 weeks apart.
Because the vaccine contains live virus, it is not given to pregnant women, people with a weakened immune system, or people with cancer of the bone marrow or lymphatic system.
The varicella vaccine is safe, and side effects are mild. In about 1 of 5 children and 1 of 3 adolescents and adults who get the vaccine, the injection site becomes painful, swollen, and red. Very occasionally, a chickenpox-like rash develops.
Taking aspirin and related drugs (salicylates) after vaccination can cause a rare but serious disorder called Reye syndrome in children under 16 years old. Thus, such children should not be given these drugs for 6 weeks after vaccination.