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Chickenpox (also called varicella) is a common and extremely infectious childhood disease that also affects adults on occasion. It produces an itchy, blistery rash that typically lasts about a week and is sometimes accompanied by a fever or other symptoms. A single attack of chickenpox almost always brings lifelong immunity against the disease. Because the symptoms of chickenpox are easily recognized and in most cases merely unpleasant rather than dangerous, treatment can almost always be carried out at home. Severe complications can develop, however, and professional medical attention is essential in some circumstances.


Before the varicella vaccine (Varivax) was released for use in 1995, nearly all of the four million children born each year in the United States contracted chickenpox, resulting in hospitalization in five of every 1,000 cases and 100 deaths. Chickenpox is caused by the varicella-zoster virus (a member of the herpes virus family), which is spread through the air or by direct contact with an infected person. Once someone has been infected with the virus, an incubation period of about 10-21 days passes before symptoms begin. The period during which infected people are able to spread the disease is believed to start one or two days before the rash breaks out and to continue until all the blisters have formed scabs, which usually happens four to 7 days after the rash breaks out but may be longer in adolescents and adults. For this reason, doctors recommend keeping children with chickenpox away from school for about a week. It is not necessary, however, to wait until all the scabs have fallen off.
Chickenpox has been a typical part of growing up for most children in the industrialized world (although this may change if the new varicella vaccine becomes more widely accepted). The disease can strike at any age, but by ages nine or 10 about 80-90% of American children have already been infected. U.S. children living in rural areas and many foreign-born children are less likely to be immune. Because almost every case of chickenpox, no matter how mild, leads to lifelong protection against further attacks, adults account for less than 5% of all cases in the United States. Study results reported by the Centers for Disease Control and Prevention (CDC) indicate that more than 90% of American adults are immune to the chickenpox virus. Adults, however, are much more likely than children to suffer dangerous complications. More than half of all chickenpox deaths occur among adults.

Causes and symptoms

A case of chickenpox usually starts without warning or with only a mild fever and a slight feeling of unwellness. Within a few hours or days small red spots begin to appear on the scalp, neck, or upper half of the trunk. After a further 12-24 hours the spots typically become itchy, fluid-filled bumps called vesicles, which continue to appear in crops for the next two to five days. In any area of skin, lesions of a variety of stages can be seen. These blisters can spread to cover much of the skin, and in some cases also may be found inside the mouth, nose, ears, vagina, or rectum. Some people develop only a few blisters, but in most cases the number reaches 250-500. The blisters soon begin to form scabs and fall off. Scarring usually does not occur unless the blisters have been scratched and become infected. Occasionally a minor and temporary darkening of the skin (called hyperpigmentation) is noticed around some of the blisters. The degree of itchiness can range from barely noticeable to extreme. Some chickenpox sufferers also have headaches, abdominal pain, or a fever. Full recovery usually takes five to 10 days after the first symptoms appear. Again, the most severe cases of the disease tend to be found among older children and adults.
Although for most people chickenpox is no more than a matter of a few days' discomfort, some groups are at risk for developing complications, the most common of which are bacterial infections of the blisters, pneumonia, dehydration, encephalitis, and hepatitis:
  • Infants. Complications occur much more often among children less than one year old than among older children. The threat is greatest to newborns, who are more at risk of death from chickenpox than any other group. Under certain circumstances, children born to mothers who contract chickenpox just prior to delivery face an increased possibility of dangerous consequences, including brain damage and death. If the infection occurs during early pregnancy, there is a small (less than 5%) risk of congenital abnormalities.
  • Immunocompromised children. Children whose immune systems have been weakened by a genetic disorder, disease, or medical treatment usually experience the most severe symptoms of any group. They have the second-highest rate of death from chickenpox.
  • Adults and children 15 and older. Among this group, the typical symptoms of chickenpox tend to strike with greater force, and the risk of complications is much higher than among young children.
Immediate medical help should always be sought when anyone in these high-risk groups contracts the disease.


Where children are concerned, especially those with recent exposure to the disease, diagnosis can usually be made at home, by a school nurse, or by a doctor over the telephone if the child's parent or caregiver is unsure that the disease is chickenpox.
A doctor should be called immediately if:
  • The child's fever goes above 102 °F (38.9 °C) or takes more than four days to disappear.
  • The child's blisters appear infected. Signs of infection include leakage of pus from the blisters or excessive redness, warmth, tenderness, or swelling around the blisters.
  • The child seems nervous, confused, unresponsive, or unusually sleepy; complains of a stiff neck or severe headache; shows signs of poor balance or has trouble walking; finds bright lights hard to look at; is having breathing problems or is coughing a lot; is complaining of chest pain; is vomiting repeatedly; or is having convulsions. These may be signs of Reye's syndrome or encephalitis, two rare but potentially dangerous conditions.


With children, treatment usually takes place in the home and focuses on reducing discomfort and fever. Because chickenpox is a viral disease, antibiotics are ineffective against it.
Applying wet compresses or bathing the child in cool or lukewarm water once a day can help the itch. Adding four to eight ounces of baking soda or one or two cups of oatmeal to the bath is a good idea (oatmeal bath packets are sold by pharmacies). Only mild soap should be used in the bath. Patting, not rubbing, is recommended for drying the child off, to prevent irritating the blisters. Calamine lotion (and some other kinds of lotions) also help to reduce itchiness. Because scratching can cause blisters to become infected and lead to scarring, the child's nails should be cut short. Of course, older children need to be warned not to scratch. For babies, light mittens or socks on the hands can help guard against scratching.
If mouth blisters make eating or drinking an unpleasant experience, cold drinks and soft, bland foods can ease the child's discomfort. Painful genital blisters can be treated with an anesthetic cream recommended by a doctor or pharmacist. Antibiotics often are prescribed if blisters become infected.
Fever and discomfort can be reduced by acetaminophen or another medication that does not contain aspirin. Aspirin and any medications that contain aspirin or other salicylates must not be used with chickenpox, for they appear to increase the chances of developing Reye's syndrome. The best idea is to consult a doctor or pharmacist if unsure about which medications are safe.
Immunocompromised chickenpox sufferers are sometimes given an antiviral drug called acyclovir (Zovirax). Studies have shown that Zovirax also lessens the symptoms of otherwise healthy children and adults who contract chickenpox, but the suggestion that it should be used to treat the disease among the general population, especially in children, is controversial.

Alternative treatment

Alternative practitioners seek to lessen the discomfort and fever caused by chickenpox. Like other practitioners, they suggest cool or lukewarm baths. Rolled oats (Avena sativa) in the bath water help relieve itching. (Oats should be placed in a sock, that is turned in the bath water to release the milky antiitch properties.) Other recommended remedies for itching include applying aloe vera, witch hazel, or herbal preparations of rosemary (Rosmarinus officinalis) and calendula (Calendual officinalis) to the blisters. Homeopathic remedies are selected on a case by case basis. Some common remedy choices are tartar emetic (antimonium tartaricum), windflower (pulsatilla), poison ivy (Rhus toxicodendron), and sulphur.


Most cases of chickenpox run their course within a week without causing lasting harm. However, there is one long-term consequence of chickenpox that strikes about 20% of the population, particularly people 50 and older. Like all herpes viruses, the varicellazoster virus never leaves the body after an episode of chickenpox, but lies dormant in the nerve cells, where it may be reactivated years later by disease or age-related weakening of the immune system. The result is shingles (also called herpes zoster), a painful nerve inflammation, accompanied by a rash, that usually affects the trunk or the face for 10 days or more. Especially in the elderly, pain, called postherpetic neuralgia, may persist at the site of the shingles for months or years. Two relatively newer drugs for treatment of shingles have become available. Both valacy-clovir (Valtrex) and famciclovir (Famvir) stop the replication of herpes zoster when administered within 72 hours of appearance of the rash. The effectiveness of these two drugs in immunocompromised patients has not been established, and Famvir was not recommended for patients under 18 years.


A substance known as varicella-zoster immune globulin (VZIG), which reduces the severity of chickenpox symptoms, is available to treat immunocompromised children and others at high risk of developing complications. It is administered by injection within 96 hours of known or suspected exposure to the disease and is not useful after that. VZIG is produced as a gamma globulin from blood of recently infected individuals.

Key terms

Acetaminophen — A drug for relieving pain and fever. Tylenol is the most common example.
Acyclovir — An antiviral drug used for combating chickenpox and other herpes viruses. Sold under the name Zovirax.
Dehydration — Excessive water loss by the body.
Encephalitis — A disease that inflames the brain.
Hepatitis — A disease that inflames the liver.
Immune system — A biochemical complex that protects the body against pathogenic organisms and other foreign bodies.
Immunocompromised — Having a damaged immune system.
Pneumonia — A disease that inflames the lungs.
Pus — A thick yellowish or greenish fluid containing inflammatory cells. Usually caused by bacterial infection.
Reye's syndrome — A rare but often fatal disease that involves the brain, liver, and kidneys.
Salicylates — Substances containing salicylic acid, which are used for relieving pain and fever. Aspirin is the most common example.
Shingles — A disease (also called herpes zoster) that causes a rash and a very painful nerve inflammation. An attack of chickenpox will eventually give rise to shingles in about 20% of the population.
Trunk — That part of the body that does not include the head, arms, and legs.
Varicella-zoster immune globulin (VZIG) — A substance that can reduce the severity of chickenpox symptoms.
Varicella-zoster virus — The virus that causes chickenpox and shingles.
Varivax — A vaccine for the prevention of chickenpox.
Virus — A tiny particle that can cause infections by duplicating itself inside a cell using the cell's own software. Antibiotics are ineffective against viruses, though antiviral drugs exist for some viruses, including chickenpox.
A vaccine for chickenpox became available in the United States in 1995 under the name Varivax. Varivax is a live, attenuated (weakened) virus vaccine. It has been proven to be 85% effective for preventing all cases of chickenpox and close to 100% effective in preventing severe cases. Side effects are normally limited to occasional soreness or redness at the injection site. CDC guidelines state that the vaccine should be given to all children (with the exception of certain high-risk groups) at 12-18 months of age, preferably when they receive their measles-mumps-rubella vaccine. For older children, up to age 12, the CDC recommends vaccination when a reliable determination that the child in question has already had chickenpox cannot be made. Vaccination also is recommended for any older child or adult considered susceptible to the disease, particularly those, such as health care workers and women of childbearing age, who face a greater likelihood of severe illness or transmitting infection. A single dose of the vaccine was once thought sufficient for children up to age 12; older children and adults received a second dose four to eight weeks later. However, an outbreak at a daycare center in 2000 brought concern in the medical community about a second vaccination for younger children, since many of the affected children had been vaccinated. Researchers began recommending a second vaccination in 2002. In 1997 the cost of two adult doses of the vaccine in the United States was about $80. Although this cost was not always covered by health insurance plans, children up to age 18 without access to the appropriate coverage could be vaccinated free of charge through the federal Vaccines for Children program. Varivax is not given to patients who already have overt signs of the disease. It was once thought unsafe for children with chronic kidney disease, but a 2003 report said the vaccination was safe in these children. The finding is important, since even chickenpox can be a serious complication in children who must undergo a kidney transplant.
The vaccine also is not recommended for pregnant women, and women should delay pregnancy for three months following a complete vaccination. The vaccine is useful when given early after exposure to chickenpox and, if given in the midst of the incubation period, it can be preventative. The Infectious Diseases Society of America stated in 2000 that immunization is recommended for all adults who have never had chickenpox.
While there was initial concern regarding the vaccine's safety and effectiveness when first released, the vaccination is gaining acceptance as numerous states require it for admittance into daycare or public school. In 2000, 59% of toddlers in the United States were immunized; up from 43.2% in 1998. A study published in 2001 indicates that the varicella vaccine is highly effective when used in clinical practice. Although evidence has not ruled out a booster shot later in life, all research addressing the vaccine's effectiveness throughout its six-year use indicates that chickenpox may be the first human herpes virus to be wiped out. Although initial concerns questioned if the vaccination might make shingles more likely, studies are beginning to show the effectiveness of the vaccine in reducing cases of that disease.



Arvin, Ann M. "Varicella Vaccine-The First Six Years." New England Journal of Medicine March 2001.
"Chickenpox Vaccine OK for Pediatric Patients." Vaccine Weekly January 22, 2003: 25.
Henderson, C. W. "Chickenpox Immunization Confirmed Effective in Adults." Vaccine Weekly September 2000: 22.
"Study: Two Vaccines Work Best." Vaccine Weekly January 8, 2003: 14.


Centers for Disease Control and Prevention. National Immunization Hotline. 1600 Clifton Rd. NE, Atlanta, GA 30333. (800) 232-2522 (English). (800) 232-0233 (Spanish).

Other "Varicella Vaccine: States Mandate Chickenpox Immunization." August 1, 2000. [cited May 3, 2001]. 〈〉.
Centers for Disease Control and Prevention. "Prevention of Varicella: Recommendations of the Advisory Committee on Immunization Practices (ACIP)." July 12, 1996. [cited December 12, 1997].
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


an acute, highly contagious, viral disease, with mild constitutional symptoms and a maculopapular vesicular skin eruption; it is a common childhood disease and is rarely severe, but it can be accompanied by severe symptoms in infants and adults. It is usually spread by either contact with blisters or droplet infection, and the average incubation period is 10 to 16 days. The period of contagion lasts about two weeks, beginning two days before the rash appears. The causative virus is human herpesvirus 3 (formerly known as varicella-zoster virus). The same virus also causes herpes zoster (shingles), with the differences in the two diseases probably reflecting differences in the response to the virus. Called also varicella.
Symptoms. Chickenpox may begin with a slight fever, headache, backache, and loss of appetite. At the same time, or a day or two later, small red spots appear, usually on the back and chest first. Within a few hours the spots enlarge and a vesicle filled with a clear fluid appears in the center of each spot, surrounded by an area of reddened skin. After a day or two, the fluid turns yellow and a crust or scab forms. This crust peels off in from 5 to 20 days. During this period the patient experiences severe itching.

The vesicles do not appear all at once, but in crops, the number of crops depending on the severity of the case. Usually the eruptions are concentrated on the back and chest, with only a few appearing on the arms, legs, and face, but in severe cases they may cover almost all of the body.
Chickenpox rash distribution. From McKinney et al., 2000.
Prevention and Treatment. Children should receive one dose of chickenpox vaccine between 12 and 18 months of age, or at any age after that if they have not had chickenpox. Individuals over age 13 who have not had chickenpox or received the vaccine should receive two doses, four to eight weeks apart. There are some contraindications to the use of the vaccine, such as women who are pregnant or are planning to conceive a child within a month.

Most cases of chickenpox are mild and require no special treatment except rest in bed and forcing fluids during the fever stage. For severe itching, emollient baths, calamine lotion, or other applications offer some relief. Since scratching the scabs may result in permanent scars and opens the way for other infections, the child's fingernails should be cut short and the hands washed often.

The Centers for Disease Control and Prevention recommends airborne and contact isolation. Other recommendations include after-exposure advisories. Varicella-zoster immune globulin (VZIG) should be used when appropriate, along with discharge of susceptible patients if possible. Exposed susceptible patients should be placed on airborne precautions beginning 10 days after exposure and continuing until 21 days after the last exposure (up to 28 days if VZIG has been given). Susceptible persons should not enter the room of patients on precautions if other immune caregivers are available. (See Atlas 2, part M.)
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


An acute contagious disease, usually occurring in children, caused by the Varicella-Zoster virus genus, Varicellovirus, a member of the family Herpesviridae, and marked by a sparse eruption of papules, which become vesicles and then pustules, like that of smallpox although less severe and varying in stages, usually with mild constitutional symptoms; incubation period is about 14-17 days.
See also: herpes zoster.
Synonym(s): chickenpox
[Mod. L. dim. of variola]
Farlex Partner Medical Dictionary © Farlex 2012



chicken pox

An acute contagious disease, primarily of children, that is caused by the varicella-zoster virus and characterized by skin eruptions, slight fever, and malaise. Also called varicella.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
Acute human herpes virus-3 (HHV-3) infection, most common before age 10; 3.5 million cases & 50 children die/year of chickenpox—US; 9,000 are hospitalized
Complications Otitis, pneumonia, 2º bacterial rashes and infections, encephalitis—5–15% mortality, 15% with permanent neurologic sequelae— ataxia, palsies, Reye syndrome, a potentially fatal complication, viral pneumonia—1:400 require hospitalization—thrombocytopenia, purpura fulminans, myocarditis, glomerulonephritis, hepatitis, myositis; after resolution of clinical disease, HHV-3 becomes latent, integrating its DNA into the dorsal root ganglion cells

Management Acyclovir may shorten duration of disease
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


Varicella, human herpesvirus type 3 Acute HHV-3 infection, most common before age 10; 3.5 million cases & 50 children die/yr of chickenpox–US; 9000 are hospitalized Clinical 2-wk incubation, then a scarlatiform prodromal rash, low-grade fever, weakness, sore throat, cough, anorexia, malaise, crops of reddish papules that become intensely pruritic vesicles, which ↑ in number for 3-4 days; itching and excoriation may cause extensive (permanent) scarring Complications Otitis, pneumonia, 2º bacterial rashes and infections, encephalitis–5-15% mortality, 15% with permanent neurologic sequelae, ataxia, palsies, Reye syndrome, a potentially fatal complication, viral pneumonia–1:400 require hospitalization, thrombocytopenia, purpura fulminans, myocarditis, glomerulonephritis, hepatitis, myositis; after resolution of clinical disease, HHV-3 becomes latent, integrating its DNA into the dorsal root ganglion cells Management Acyclovir may shorten duration of disease. See Chickenpox vaccine, Shingles.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


An acute contagious disease, usually occurring in children, caused by the varicella-zoster virus and marked by a sparse eruption of papules, which become vesicles and then pustules, usually with mild constitutional symptoms; incubation period is about 14-17 days.
Synonym(s): chickenpox.
[Mod. L. dim. of variola]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


an acute, contagious disease distinguished by slight fever and skin vesicles, and caused by the herpes varicella-zoster virus. The same virus can cause shingles in adults, a painful inflammation along the path of a major nerve, frequently across the back or sides.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005


Acute contagious disease, usually occurring in children, caused by the Varicella-Zoster virus genus, Varicellovirus; marked by a sparse eruption of papules, which become vesicles and then pustules, like that of smallpox although less severe and varying in stages, usually with mild constitutional symptoms; incubation period is about 14-17 days.
Synonym(s): chickenpox.
[Mod. L. dim. of variola]
Medical Dictionary for the Dental Professions © Farlex 2012

Patient discussion about chickenpox

Q. How contagious is chicken pox? I just found out that a kid in my son's preschool has chicken pox. What are the chances my son got it too? He hasn't been vaccinated against it. He is 3 years old.

A. take it easy Issac. chicken pox is a typical disease children have. me too i still live. the most important thing is that your child does not scratch his face because it can make skin damages. your 3 year old child has only now with 3 years a more or less correct working lymph system. perhaps this link-page can help you too:

before you would like to go on with any vaccination, you should check out this very long list of links:

at the bottom you will also find links in english. vaccinations in general are very disputable/dubious and it is probably time that we learn about it.

Q. Is chicken pox dangerous to my fetus? I am pregnant and have never had chicken pox before. My daughter is 2 years old and has not had chicken pox before and hasn't been vaccinated against it either. If she does catch chicken pox can this be dangerous to me or the fetus?

A. perhaps it will be then useful if the chicken pox would appear that you have then a separate room if necessary (quarantine).
i advice you also to inform yourself and build your own opinion with this link-page:

before you would like to go on with any vaccination, you should check out this very long list of links:

at the bottom you will also find links in english. vaccinations in general are very disputable/dubious and it is probably time that we learn about it.

More discussions about chickenpox
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References in periodicals archive ?
"I felt terrible for a couple of days and I couldn't believe it when the doctor told me I'd got chicken-pox.
He used to take me to kids' parties so that I would catch it - they call them 'chicken-pox parties' but I never did.