What is chickenpox?


Chickenpox: Overview

Chickenpox is a common disease caused by the varicella virus. Chickenpox causes an itchy rash and red spots or blisters (pox) on the skin all over the body. You also can have blisters on the scalp and in the eye. But getting the chickenpox vaccine can lower your risk of getting this disease.

Chickenpox is most contagious from 2 to 3 days before the rash develops until no new blisters form and all the blisters have crusted over. That may be 7 days or more after the blisters first appear. It may take up to 2 weeks for the scabs to go away. Most healthy children need only home treatment for chickenpox. People who are older than age 12, are pregnant, or have a weak immune system may need medicine.


Chickenpox (varicella) is an illness that causes an itchy rash and red spots or blisters all over the body. The blisters burst and crust over after several days. Chickenpox is very contagious. People who are infected with the virus can spread it before they have any symptoms.

Chickenpox usually isn't serious in children. It can be more serious in newborns, teenagers, adults, pregnant women, and people who have a weakened immune system.

There is a vaccine that can prevent chickenpox.

Chickenpox rash

Typical chickenpox rash on back of a child, with close-up showing blisters and crusted sores

Chickenpox (varicella) is a contagious illness that causes an itchy rash and red spots or blisters (pox) all over the body. It takes about 1 or 2 days for a chickenpox red spot (macule) to go through all of its stages. This includes blistering, bursting, drying, and crusting over. New red spots appear every day for up to 5 to 7 days.

What are the symptoms of chickenpox?

The first symptoms of chickenpox usually start about 14 to 16 days after contact with a person infected with the virus. These symptoms include:

  • A fever.
  • Feeling sick, tired, and sluggish.
  • Having little or no appetite.
  • Headache, cough, and sore throat.

These symptoms are usually mild in children, but they can be severe in teens and adults. The symptoms may last throughout the illness.

The itchy chickenpox rash usually appears about 1 or 2 days after the first symptoms start. After a red spot appears, it goes through stages. It will blister, burst, dry, and crust over. New spots will appear every day for up to 5 to 7 days.

It usually takes about 6 days for a blister to crust over. When all the blisters have crusted over, the person with chickenpox can go back to day care, school, or work.

How is chickenpox treated?

Treatment for chickenpox depends on your age, your health, how long it's been since you were exposed to the virus, and your symptoms.

Home treatment includes rest and medicines to reduce fever and itching. Read and follow all instructions on the label. Do not give aspirin to anyone younger than 20. It has been linked to Reye syndrome, a serious illness. Soaking in oatmeal baths also helps with itching.

Most healthy children need only home treatment for chickenpox. Healthy teens and adults with chickenpox often have more severe symptoms than children and are at higher risk for problems. If you are older than age 12, are pregnant, or have a weak immune system, your doctor may want to give you a medicine or vaccine that helps protect you from the virus.

People with long-term diseases or other health problems may need more treatment. They may need immunoglobulin treatment (IG) or antiviral medicine.

How can you prevent chickenpox?

You can prevent chickenpox with the chickenpox vaccine. Children get this vaccine as part of their routine immunizations.

If you've never had chickenpox or the vaccine, you have no immunity against the virus. If you or your child isn't immune, you can prevent chickenpox by getting the vaccine.

The vaccine is recommended for:

  • All healthy children 12 months of age and older who haven't had chickenpox.
  • Healthy people who aren't sure if they've had the vaccine or chickenpox as a child.
  • Women who are planning to get pregnant but aren't pregnant yet. Chickenpox and pregnancy can be a dangerous combination. Getting the vaccine when not pregnant prevents complications of chickenpox during pregnancy. Talk to your doctor about the right timing for the vaccine.

You can help prevent chickenpox by avoiding close contact with people who are infected with the virus. This is even more important if you have a weak immune system.

Preventing chickenpox after being exposed to the virus

If you've been in contact with a person who has chickenpox and aren't sure if you're immune, a shot of the vaccine may prevent the illness. Or it may make the illness milder.

If you can't have the chickenpox vaccine (for example, during pregnancy), a shot of antibodies (immunoglobulin) or an antiviral medicine may help prevent the chickenpox.

How is chickenpox diagnosed?

Your doctor will ask about symptoms and do an exam. A healthy child with chickenpox symptoms may not need to visit a doctor. You may be able to describe the symptoms to the doctor over the phone. Teens, adults, pregnant women, and people with health problems need to see a doctor for chickenpox.

How do you care for someone who has chickenpox?

Most healthy children need only home treatment. But all teens and adults with chickenpox need to see a doctor to help prevent serious problems. Using over-the-counter medicines, taking oatmeal baths, and applying cool compresses can help relieve symptoms such as fever and itching. Check with your doctor before you give medicine to your child.

How does chickenpox spread?

Chickenpox can spread easily. You can get it from an infected person who sneezes, coughs, or shares food or drinks. You can also get it if you touch the fluid from a chickenpox blister.

A person who has chickenpox can spread the virus even before he or she has any symptoms. Chickenpox is most easily spread from 1 to 2 days before the rash appears until all the blisters have crusted over.

Chickenpox usually doesn't spread to people who have had the illness or the chickenpox vaccine.

What are the complications of chickenpox?

After you've had chickenpox, you aren't likely to get it again. But the virus stays in your body long after you get over the illness. If the virus becomes active again, it can cause a painful viral infection called shingles, usually when you are an older adult.

Skin infection is the most common complication for children under age 5. An infection can form after the rash is scratched. Scratching allows bacteria from the skin or under the fingernails to get into a chickenpox blister. The infection can become serious if it isn't treated. An infected blister also may leave a scar.

Other complications may include pneumonia or encephalitis (inflammation in the brain). These complications are rare, but can be very serious.

Chickenpox during pregnancy can cause birth defects or serious newborn infection.

What causes chickenpox?

Chickenpox is caused by the varicella-zoster virus. It can spread easily. You can get it from an infected person who sneezes, coughs, or shares food or drinks. You can also get it if you touch the fluid from a chickenpox blister.

What is chickenpox?

Chickenpox (varicella) is a contagious illness that causes an itchy rash and red spots or blisters (pox) all over the body. Chickenpox can cause problems for pregnant women, newborns, teens and adults, and people who have immune system problems that make it hard for the body to fight infection.

Chickenpox usually isn't a serious health problem in healthy children. But children who have chickenpox need to stay home from school so they don't spread it to others.

Controlling the itch from chickenpox

Home treatment methods can help reduce the itchiness of the chickenpox rash. Try the following suggestions to make you or your child more comfortable and keep scratching under control.

  • Take warm to cool baths to help relieve itching.

    Take baths for 20 to 30 minutes as often as needed to stay clean and soothe your itchy skin. Always stay with young children when they are in a bathtub.

    • Do not use soap, or use only a mild soap. Soaps that are made for sensitive skin or recommended for babies are usually mild.
    • Add a handful of oatmeal (ground to a powder) to your bath. Or you can try an oatmeal bath product, such as Aveeno.
    • Blot the skin dry after bathing. Don't rub the skin.
  • Apply cool compresses to itchy areas.
    • Use a soft, absorbent cloth, such as a soft washcloth. Wet the cloth with cool water and apply the cool compress directly to the skin.
    • You can also make an oatmeal paste and apply it to itchy areas. Take some oatmeal that's been ground to a powder, and mix it with a little bit of warm water to make a paste. Spread the paste on a paper towel. Put the paste side of the towel against the itchy area of skin. Hold it there for 10 to 15 minutes. Then gently wash and pat the skin dry.
  • Apply soothing lotions that can help dry chickenpox blisters.

    But talk to your doctor before using lotions that contain antihistamines. You could try lotions with:

    • Phenol, menthol, and camphor, such as calamine lotion.
    • Oatmeal, such as Aveeno Lotion.
  • Use general hygiene practices to help prevent skin irritation and scratching.
    • Wear loose-fitting cotton clothing.
    • Change clothes and bedsheets daily.
    • Use a mild laundry detergent if clothes or linens seem to be irritating the skin.
  • Avoid using antihistamine lotions.

    You may accidentally apply too much medicine, which can be harmful. Ingredients to avoid include:

    • Diphenhydramine.
    • Lidocaine.
    • Pramoxine.
  • Try antihistamines taken by mouth.

    Sometimes they help relieve itching. This can help prevent you or your child from scratching the rash and blisters, especially during sleep. Some antihistamines can be bought over-the-counter. If you use them, carefully follow the directions on the label. Check with your child's doctor before you give them to your child.

  • Avoid getting hot and sweating.

    These trigger itching.

  • Stay out of sunlight.

    A child can play outside in the shade.

Chickenpox: When to call

Call your doctor now or seek immediate medical care if:

  • You have a new or worsening cough, and you are short of breath.
  • You have a fever with a stiff neck or a severe headache.
  • You are sensitive to light or feel very sleepy or confused.
  • You have eye pain or drainage.
  • You have signs of an infection, such as:
    • Increased pain, swelling, warmth, or redness.
    • Red streaks leading from the chickenpox blisters.
    • Pus draining from the blisters.
    • A fever.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You do not get better as expected.

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