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Childhood Vaccinations

        Health | Family Care

Chickenpox Vaccine
Today, most children between the age of 12 and 18 months receive the chickenpox vaccine.
Today, most children between the age of 12 and 18 months receive the chickenpox vaccine.
©2006 Publications International, Ltd.

The chickenpox vaccine is relatively new, but it sure comes as a relief for any parent who has had to try to keep an itchy youngster from scratching those small red bumps. Read on for more information about the varicella vaccine.

Chickenpox Basics

The varicella-zoster virus, a member of the herpesvirus family, causes chickenpox. The virus is spread through the air when someone who has it coughs or sneezes, spreading viral particles that are then inhaled by a nonimmune person. Contact with the fluid of chickenpox blisters can also spread the virus, but it does not live long on inanimate objects, such as doorknobs.

Chickenpox causes a remarkably itchy skin rash that is easy to identify because of its small red bumps that look like insect bites or pimples. The bumps first appear on the back, face, scalp, and abdomen, and then can spread nearly everywhere else, including the mouth, nose, ears, and genitals, but they are concentrated on the face and body.

The bumps develop into blisters that are filled with clear fluid that later turns cloudy. These blisters break and develop into open sores and then dry brown scabs. All stages of the lesions can be present at the same time. Chickenpox usually lasts about seven days in children but several days longer in adults.

Who's at Risk for Chickenpox

Before the chickenpox vaccine was available, children younger than 15 were the particular risk group, but anyone could be infected. Chickenpox is usually a mild illness, but complications, such as viral pneumonia, inflammation of the brain (encephalitis), and, more commonly, bacterial infection of the skin can occur. Anyone who experiences chickenpox as a child is at risk for shingles later in life (see Shingles Vaccine for more information).

Defensive Measures Against Chickenpox

Chickenpox is very contagious, but immunization with the varicella vaccine is an effective weapon against it. Beyond that, avoid contact with anyone who has chickenpox. If contact is unavoidable, wash hands and disinfect surfaces, particularly when dealing with the fluid-filled blisters.

The varicella vaccine has been administered since 1995 and is one of the routine immunizations given to children between 12 months and 18 months of age. The vaccine is more than 95 percent effective in preventing the severest form of the virus and is 80 to 90 percent effective at preventing milder forms of the infection. Children who develop chickenpox after being vaccinated will experience a weaker form of the disease.

Older children and adolescents who haven't received the vaccine, and who have not had chickenpox, should be immunized. However, instead of a single vaccine dose, adolescents 12 and older require two doses given a minimum of four weeks apart.

It's also important to watch the calendar. Chickenpox occurs most often in late winter and early spring. An infected person is contagious two days before the rash appears and until all the blisters have formed scabs. A child with chickenpox should be kept out of school or day care until all the blisters have dried, which is usually about one week.

Susceptible pregnant women should steer clear of a person with chickenpox. If a pregnant woman who isn't immune gets the disease, her baby has a small risk of birth defects, and the mother has a higher risk of developing serious complications, such as varicella pneumonia.

Newborns born to women who develop chickenpox right before or right after delivery can develop life-threatening varicella. These infants can get some protection from varicella-zoster immune globulin (VZIG). VZIG also can be given to high-risk children, such as those with leukemia or those taking immune-suppressing drugs.

Never give aspirin to a child who gets chickenpox because of the risk of Reye's syndrome, a rare, but potentially deadly, disease.

Healthy children who have had chickenpox don't need to be vaccinated; they are usually immune to the disease for life.

Diphtheria is a bacterial infection that affects the nose and throat. Learn more about the diphtheria vaccine on the next page.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.


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