Vaccines by disease: Learning more about the varicella (chickenpox) vaccine

This vaccine is imperative because even though many cases of chickenpox are mild, this highly contagious virus can cause serious complications such as severe skin infections that sometimes leave permanent scars, pneumonia, inflammation of the kidneys, arthritis, brain infection (rare) or even death. Patients who have chickenpox are predisposed to infection with group A Streptococcus (GAS) and Staphylococcus aureus bacteria, which can be life threatening.

Chickenpox is more likely to be severe in adolescents and adults and in anyone who has an abnormal immune system or is taking medicines that affect the immune system. Pregnant women who get chickenpox for the first time may develop severe illness themselves or may miscarry. There may be abnormalities in the fetus, such as congenital varicella syndrome. Even when people recover from chickenpox, painful shingles can develop later in life.

Prevention is the key to not contracting chickenpox, and the most effective preventive method is vaccination.

Who should be vaccinated for chickenpox? Children who are between the ages of 12 months to 18 months Children who are between the ages of 4 to 6 years, adolescents and adults who have never had chickenpox or have not yet been vaccinated Some people should not receive the chickenpox vaccine including: People who have had a life-threatening allergic reaction to gelatin, the antibiotic neomycin or a previous dose of the chickenpox vaccine  People with HIV/AIDS, weakened immune systems, cancer or low platelet counts; who are being treated for another condition with steroids; or who have recently received a blood transfusion should speak with their primary health care provider about this vaccine. Unvaccinated pregnant women. Women who are planning to become pregnant should wait one month after receiving the chickenpox vaccine to try to become pregnant. People living with pregnant women may receive this vaccine if it is indicated for them.

When did the vaccine for chickenpox become available?
The varicella vaccine was first recommended for routine use in the United States in 1995. In 2006, a combination vaccine called MMRV that combines varicella with measles, mumps and rubella (MMR) was licensed for use in the United States for children from 1 to 12 years of age.

How does someone become infected with the chickenpox?
Chickenpox is caused by a highly contagious virus and is easily spread by direct person-to-person contact or rarely by airborne contact. Patients with chickenpox are contagious until the rash has crusted over completely.

How effective is the chickenpox vaccine?
This vaccine has been proven to be effective in at least 90 percent of children and adolescents who receive two doses. Anyone who contracts chickenpox after having been vaccinated usually develops a much milder form of the disease.

In June 2006, the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices recommended that all children, adolescents and adults receive a total of two doses of varicella vaccine to achieve optimal protection.

What is the dosage schedule for the chickenpox vaccine?

• The first dose should be given to infants between 12 and 15 months of age and the second dose between 4 and 6 years of age.
• Children, teens and adults who have not had chickenpox or were not vaccinated against the disease should receive two doses of varicella vaccine at least 4 to 8 weeks apart.

Review the vaccination schedule for those who start late on a vaccine or are more than one month behind.

Are there any side effects of this vaccine?
The majority of patients who receive the chickenpox vaccine have no side effects.

Mild side effects may include:

• injection-site soreness
• fever
• mild rash

A moderate, rare side effect of this vaccine is seizure brought on by a fever. A very rare serious side effect is pneumonia.

Can you get chickenpox from the vaccine?
Because varicella is a live, weakened virus, about 1 percent of those who receive this vaccine will develop a chickenpox rash, which is a significantly milder form of chickenpox than if it develops naturally.

How do I learn more about this vaccine?
The best person to ask about this or any vaccine is your child’s pediatrician or your primary health care provider. Your provider can answer your questions and give you more information on the chickenpox vaccine.

Immunization is the best thing you can do for your child and yourself to protect
against chickenpox.