Chicken Pox Vaccine
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The varicella zoster virus, better known as chicken pox, causes an itchy blister like skin rash that covers the face, scalp, and trunk. It is accompanied by fever, headache, malaise, and loss of appetite. In most children the disease is an annoyance, but in children who already have a suppressed immune system serious complications can accompany the infection. Approximately 9,000 individuals are hospitalized each year from chicken pox infections, 80 percent of which are children. Around 50 children each year die from complications of the disease.
A vaccine for chickenpox is now available for immunization which is 70 to 90 percent effective in preventing people from getting the disease. Those individuals who do develop the disease after immunization will have a milder case than non-immunized individuals. The vaccine will be integrated into immunization schedules for children. The vaccine is being recomended as a single shot for children ages 12 months to 12 years who have not had the disease. Ages 13 to adult who have not had chicken pox should receive two doses four to eight weeks apart. Infants under the age of one cannot receive the vaccine, but their exposure to the disease should be minimized as older children are vaccinated. Your physician may perform a laboratory test to detect whether you have been exposed to the virus prior to giving the vaccine. Some individuals are infected with the virus and create antibodies against it, but never have a rash that is recognized as chicken pox. These individuals would not benefit from being vaccinated.
The vaccine was more than a decade in development by Merck and the company has spent two years to prove to the FDA that the vaccine was safe and the effect was durable. The vaccine was tested on 9,545 healthy children and 1, 648 teenagers and adults. There are several unanswered questions about the vaccine, including:
- How long it protects against chicken pox and whether booster shots will be required to keep immunity.
- If the vaccine will have any beneficial effect for older adults in the prevention of shingles. Shingles results when an adult loses their immunity to the varicella zoster virus. It appears as a rash with painful blister like qualities generally in one area of the body.
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