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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.
What causes it, and how is it spread?
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 are the symptoms?
The first symptoms of chickenpox are fever, little or no appetite, headache, cough, and sore throat. The itchy rash appears about 1 or 2 days later. New spots appear for about 5 to 7 days. It usually takes 6 days for a blister to crust over.
How is it 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 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. Most healthy children need only home treatment for chickenpox. People older than age 12 or who are pregnant or have a weak immune system may need medicine.
How can you prevent it?
If you or your child has never had chickenpox or the chickenpox vaccine, you have no immunity against the virus. You can prevent chickenpox by getting the vaccine. Pregnant women may be able to get a shot of antibodies (immunoglobulin) or an antiviral medicine to prevent chickenpox.
How it Spreads
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.
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.
The first symptoms of chickenpox usually start about 14 to 16 days after contact with a person infected with the virus.
These first symptoms include:
- A fever.
- Feeling sick, tired, and sluggish.
- Having little or no appetite.
- Headache, cough, and sore throat.
The first symptoms are usually mild in children, but they can be severe in teens and adults. These symptoms may last throughout the illness.
The itchy chickenpox rash usually appears about 1 or 2 days after the first symptoms start.
After a chickenpox red spot appears, it goes through stages. It will blister, burst, dry, and crust over. New red spots will appear every day for about 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.
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.
Problems caused by 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.
When to Call a Doctor
Call your doctor now if you or your child with chickenpox has:
- A severe headache or constant vomiting, sensitivity to bright light, or unusual sleepiness or confusion. These may be signs of inflammation of the brain (encephalitis).
- Problems breathing or persistent coughing. These may be signs of varicella pneumonia.
- Red, warm, and sore skin, or if the chickenpox rash changes to bigger open sores. These may be signs of serious skin infection.
Call for an appointment with your doctor if:
- You are older than age 12, you aren't sure if you have ever had chickenpox or the vaccine, and you have been exposed to chickenpox.
- You or your child has a weak immune system and has been exposed to chickenpox.
- You are pregnant and have been exposed to chickenpox.
- You or your child has chickenpox and any of the following:
- A fever that lasts longer than 24 hours
- Severe itching that cannot be relieved by home treatment
- Chickenpox rash on the eyeball
- A rash that lasts longer than 2 weeks
If you are a teen or adult, are pregnant, or have a weak immune system, it's important to see your doctor as soon as you think you've been exposed to the chickenpox virus. Your doctor may want to give you a medicine that helps protect you from the virus.
A healthy child with chickenpox symptoms may not need to visit a doctor. You may be able to describe your child's symptoms to the doctor over the phone. Then your child won't have to leave the house and risk spreading the virus to others. But it's important to check with your doctor to find out if your child needs to be seen.
If you go to a doctor's office, ask if you need to take any precautions when you arrive to avoid spreading the infection. For example, office staff may take you directly to an exam room when you arrive, rather than have you wait in the lobby.
Exams and Tests
Chickenpox often can be diagnosed based on how the chickenpox rash looks.
Your doctor will ask you questions and will do an exam. During the exam, the doctor should be able to tell if you or your child has chickenpox.
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 or a weak immune system need to see a doctor as soon as they think they might have chickenpox. This is very important for pregnant women to prevent birth defects and infection.
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.
Most healthy children with chickenpox need only home treatment. But all teens and adults with chickenpox need to see a doctor.
If you have chickenpox, it's best to stay quiet and rest. Over-the-counter medicines can help relieve symptoms like itching and fever.
Before you give medicine to your sick child, check with your doctor about which medicines to give and how to give them.
The chickenpox rash itches. Scratching the blisters may cause a skin infection, or scars may form after the blisters heal. Try taking oatmeal baths and using cool compresses. You can also take oral antihistamines.
Use over-the-counter fever medicines only when fever is causing discomfort. 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. Call your doctor if you or your child has a fever that lasts longer than 24 hours.
Reduce the itch
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:
- 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.
Current as of: June 13, 2023
Author: Healthwise Staff
Clinical Review Board: All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
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