Chickenpox is a highly contagious disease.

Before the vaccine became available in 1995, about 4 million people in the United States got chickenpox every year. Thousands of people were hospitalized with serious complications, such as pneumonia and encephalitis. About 100 people died each year, most of them young children who had been healthy before they got chickenpox.

Thanks to the vaccine, hospital stays and deaths from chickenpox have dropped sharply. But outbreaks still occur, putting children at risk. For this reason, doctors urge parents to get their children vaccinated against chickenpox. Some teens and adults should also get the vaccine.

How effective is the vaccine?
The chickenpox vaccine is very effective. Almost nine out of 10 people who get the vaccine are completely protected against the disease. If a person does get chickenpox after being vaccinated, the symptoms are usually very mild.

Is it safe?
The chickenpox vaccine is safe. It has been used for over a decade in millions of children. Some have mild side effects, but serious side effects are very rare. It's much safer to get the vaccine than to get chickenpox.

When should my child get vaccinated?
Your child should get a total of two doses of the vaccine:

• The first is given between 12 and 15 months of age.
• The second dose is given between 4 and 6 years of age.

It is important for the child to get both doses of the vaccine to be protected for life against chickenpox.

The chickenpox vaccine is one of the standard immunizations recommended for children. It is usually given at the same time as the measles-mumps-rubella (MMR) vaccine.

Who else should get vaccinated?
Most people older than 13 who were not vaccinated as children and have not had chickenpox should get two shots at least 28 days apart. The disease can be especially dangerous in teens and adults.

A person who has gotten only one shot needs a second "booster" shot to be fully protected.

Who should not get the vaccine?
The chickenpox vaccine is not for everyone. People who should not be vaccinated include:

• Anyone who has ever had a severe allergic reaction to gelatin, the antibiotic neomycin or a previous dose of the chickenpox vaccine.
• Women who are pregnant should wait until after they have delivered to get the vaccine.
• Women should avoid getting pregnant for one month after getting the chickenpox vaccine.

Talk to your doctor about whether your child should get the vaccine if the child:

• Has HIV/AIDS or another disease that weakens the immune system
• Is being treated with drugs that affect the immune system, such as steroids, for longer than two weeks
• Has any type of cancer
• Is being treated for cancer with radiation or drugs
• Has recently been given a blood transfusion or other blood products

If your child has a fever or is ill, your doctor may tell you to wait until he or she is well before getting the child vaccinated.

Talk to your doctor if you have any questions about whether vaccination is right for your child.

Does a child need to be vaccinated if he or she has already had chickenpox?
A child who has had chickenpox does not need to be vaccinated. Having the illness gives lifelong immunity.

Related Articles Easing Your Child's Fear of Needles Chickenpox: Prevention Is the Best Medicine Adult Chickenpox: Can a Vaccine Prevent It?

External Sources Centers for Disease Control and Prevention. Prevention of varicella: recommendations of the Advisory Committee on Immunization Practices (ACIP). Morbidity and Mortality Weekly Review. 2007;56(RR04):1-40.. Accessed October 16, 2008 Centers for Disease Control and Prevention. 2008 child and adolescent immunization schedules. . Accessed October 16, 2008 Centers for Disease Control and Prevention. Chickenpox vaccine: what you need to know.. Accessed October 16, 2008 Centers for Disease Control and Prevention. Who should NOT get vaccinated with these vaccines? Varicella. . Accessed October 16, 2008

This article was reviewed and updated 08-01-2009.