Chicken pox is a highly contagious childhood disease that, until the vaccine became available in the mid-1990s, affected nearly all children under the age of ten years. In the late 1980s, there were a reported 3.9 million cases of chicken pox each year in the United States. The American Academy of Pediatrics estimates that more than 95% of the population contracted chicken pox prior to the availability of the vaccine. Most cases are fairly mild, with the child suffering seven to ten days of discomfort. A small percentage of chicken pox sufferers require hospitalization. Chicken pox is highly contagious. A person with chicken pox is contagious from one to two days before the outbreak of the chicken pox rash, and for six days after the rash erupts. After being exposed, a person will show symptoms of chicken pox within 10-21 days. A person can only get chicken pox once.
Symptoms of the disease include a mild fever for one to two days before the appearance of a skin rash (small, watery blisters) that begins on the scalp and body and spreads within three to four days over the entire body. A typical case of chicken pox involves between 250 and 500 blisters over the body. These dry into scabs after three or four days. The blisters are itchy, and children should be discouraged from scratching and their fingernails should be kept very short for the duration of the chicken pox case. There are commercial products available, such as oatmeal baths and calamine lotion, that may help to relieve the itching of chicken pox. Although complications from chicken pox are generally uncommon, the most common one is bacterial infection of the skin, initiated at the site of a chicken pox blister that has broken or was scratched open. Other complications include viral or bacterial pneumonia and encephalitis (swelling of the brain). The groups that are at higher risk for developing complications are anyone with a weak immune system; children with lung diseases; children with eczema or other skin conditions; infants under one year of age; premature infants whose mothers have not had chicken pox; and newborns whose mothers had chicken pox around the time of delivery. When an adult gets chicken pox, the case is usually more severe and lasts longer. Adults are 10 times more likely than children to require hospitalization from chicken pox. An oral anti-viral drug, acyclovir, may be prescribed for anyone at risk of developing a severe case of chicken pox. Acyclovir is only effective if it is given within 24 hours of the outbreak of the chicken pox blisters. Shingles, known medically as herpes zoster, is a condition of the nerves caused by the chicken pox virus that affects between 10-20% of all people who have ever had chicken pox. Once a person has had chicken pox, the virus remains in his or her nerve roots for the rest of his or her life. The virus most commonly reappears as shingles at age 50 or older, although shingles can occur anytime. Shingles cause numbness, itching, or severe pain in skin areas where the affected nerve root is located, and within about three days, causes clusters of blisters to form along the affected nerve. The blisters last two to three weeks.
Bellet, Paul S. The Diagnostic Approach to Common Symptoms and Signs in Infants, Children, and Adolescents. New York: Lea and Febiger, 1989.
dayman, Charles B., and Jeffrey R. M. Kunz. (eds.) Children: How to Understand Their Symptoms. New York: Random House, 1986.
Garwood, John, and Amanda Bennett. Your Child's Symptoms. New York: Berkeley Books, 1995.
National Institute of Allergy and Infectious Diseases (NIAID)
Address: 9000 Rockville Pike
NIH Building 31, Room 7A50
Bethesda, MD 20892-2520
Telephone: (301) 496-5717
(Arm of the National Institutes of Health that deals with allergies and diseases.)
March of Dimes Birth Defects Foundation
Address: 1275 Mamaroneck Avenue
White Plains, NY 10605
Telephone: (914) 428-7100
(Publishes information sheets on specific birth defects and related topics, including Chicken Pox During Pregnancy.)