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Varicella (Chicken Pox)

  • Definition

    Varicella, otherwise known as chicken pox, is a generalized infection caused by the varicella zoster virus. It is an extremely contagious disease that is characterized by a blistery rash. It occurs most frequently in children, between the ages of five and eight. Less than 20 percent of all cases in the U.S. affect people over the age of 15. Chicken pox is transmitted so easily that almost everyone gets the disease.


    Chicken pox is contracted by touching an infected person's blisters or anything that has been contaminated by contact with them. The virus is also thought to be airborne since it may be caught from an infected person by coughing and sneezing even before the rash develops. Another way to get chicken pox is by exposure to shingles, a localized rash caused by the same virus.

    The incubation period (time between exposure to the illness and the appearance of symptoms) of chicken pox is 10 to 21 days. It is contagious for about six to eight days after the rash appears or until all of the blisters have dried out.


    There are usually no symptoms before the rash occurs but occasionally there is fatigue and some fever in the 24 hours before the rash is noticed. The typical rash goes through a number of stages:

    1. First it appears as flat red splotches

    2. They become raised and may resemble small pimples

    3. They develop into small blisters, called vesicles, which are very fragile

    4. They may look like drops of water on a red base

    5. As the vesicles break, the sores become pustular and form a crust - the crust is made of dried serum, and not true pus. The crust falls away between days nine and 13. (itching is severe in the pustular stage.)

    The vesicles tend to appear in crops within two to six days. All stages may be present in the same area. They often appear on the scalp and in the mouth, and then spread to the rest of the body, but they may begin anywhere. They are most numerous over shoulders, chest and back. There may be only a few sores, or there may be hundreds.

    The doctor should be called if the rash involves an eye, if fever is higher than 103, if there is much vomiting, or if there are signs of bacterial infection (such as a green or yellow discharge from the blisters, or any blisters with red streaks radiating outwards). Go to the emergency room if there is difficulty breathing or if the person is confused and disoriented or has seizures.


    The major problem in dealing with chicken pox is control of the intense itching and reduction of the fever. Warm baths containing baking soda can help; sometimes cool compresses or cool baths will calm itching.

    Aspirin should not be used for children or adolescents with chicken pox because of the associated risk of reye's syndrome, a rare but life-threatening condition. Fever can be treated with acetaminophen or ibuprofren.

    Cut the fingernails or use gloves to prevent skin damage from intense scratching. When lesions occur in the mouth, gargling with salt water may provide comfort. Drink cold fluids, and avoid hot, spicy and acidic foods (orange juice).

    Hands should be washed three times a day and all of the skin should be kept gently but scrupulously clean in order to prevent a complicating bacterial infection. A minor bacterial infection will respond to soap and time. If it becomes severe and results in the return of a fever, see a physician.

    Scratching and infection can result in permanent scars. A visit to the physician may not be necessary, unless a complication seems possible.

    Acyclovir (Zovirax), a drug primarily used for treating herpes simplex infections in adults, is a safe and effective treatment for chicken pox in normal children, especially older children and teenagers, when therapy is initiated during the first 24 hours of a rash. Adverse effects of acyclovir are minimal, the most common being gastrointestinal.

    Because chickenpox is extremely contagious, keep children home from daycare or school until the blisters are all crusted over.


    Is someone contagious 24 hours prior to having a fever?

    At what age is the greatest risk of complications?

    Do you recommend calamine lotion to help the itching?

    Do you recommend any medications to decrease the severity of this virus? What are the side effects?

    Are showers less likely to spread the disease verses baths?

    Can you get chicken pox a second time? Does having a mild case or a severe case affect your chances of acquiring the virus?

    As a parent, what can I do to avoid acquiring chicken pox for the first time or as a repeat?

    Does chicken pox increase the chances of developing shingles?

    What are some of the complications?

    What are the signs and symptoms that should be reported to the doctor?

    Are there any measures that can help prevent scarring, such as vitamin e?

    Chicken pox can be prevented through vaccination (now recommended by almost all major national health and public health groups). Recommendations are:

    • Children and Adolescents: Healthy children can be vaccinated, optimally at age 12 to 18 months or anytime up until the age of 13, if they have no history of chicken pox. Adolescents 13 years and older who have no history of chicken pox, should receive two doses of vaccine four to eight weeks apart. Duration of immunity after vaccination is not completely known. Re-vaccination with a booster dose may be required to sustain immunity through adulthood.
    • Adults: Two doses of varicella vaccine four to eight weeks apart are recommended for healthy adults with no history of chicken pox or previous vaccination. Health care workers, daycare workers, employees of colleges or residential facilities, family members of immunocompromised individuals, and others who live or work in environments in which transmission may be easy are particularly encouraged to receive vaccination.