Chicken pox (Varicella)
Topic Overview
What is chicken pox?
Chicken pox is a common illness that causes an itchy rash and red spots or blisters (pox) all over the body. It is most common in children, but most people will get chicken pox at some point in their lives if they have not had the chicken pox vaccine.
Chicken pox usually isn't serious in healthy children. But it 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.
After you have had chicken pox, you are not 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.
What causes chicken pox, and how is it spread?
Chicken pox 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 chicken pox blister.
A person who has chicken pox can spread the virus even before he or she has any symptoms. Chicken pox is most easily spread from 2 to 3 days before the rash appears until all the blisters have crusted over.
You are at risk for chicken pox if you have never had the illness and have not had the chicken pox vaccine. If someone you live with gets chicken pox, your risk is even higher because of the close contact.
What are the symptoms?
The first symptoms of chicken pox often are a fever, a headache, and a sore throat. You or your child may feel sick, tired, and not very hungry. The chicken pox rash
usually appears about 1 or 2 days after the first symptoms start. Some children get the chicken pox rash without having a fever or other early symptoms.
It usually takes 14 to 16 days to get the symptoms of chicken pox after you have been around someone with the virus. This is called the incubation period.
After a chicken pox red spot appears, it usually takes about 1 or 2 days for the spot to go through all its stages. This includes blistering, bursting, drying, and crusting over. New red spots will appear every day for up to 5 to 7 days.
You or your child can go back to work, school, or daycare when all blisters have crusted over. This is usually about 10 days after the first symptoms start.
Other illnesses can have symptoms like those of chicken pox. For this reason, you may think you have had chicken pox twice when instead you have had two different infections.
How is chicken pox diagnosed?
Your doctor will ask you about your symptoms and will examine you. This usually gives your doctor enough information to find out if you have chicken pox.
Healthy children with chicken pox 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 is important to check with your doctor to find out if he or she wants to see your child.
Teenagers, adults, pregnant women, and people with health problems need to see a doctor for chicken pox. This is especially important for pregnant women, since chicken pox during early pregnancy can cause birth defects. Call first to make an appointment and to discuss whether you need to take any steps to avoid spreading the virus when you arrive. For example, office staff may take you straight to an examination room, rather than have you wait in the lobby.
How is it treated?
Most healthy children and adults need only home treatment for chicken pox. Home treatment includes resting and taking medicines to reduce fever and itching. You also can soak in oatmeal baths to help with itching.
People with long-term diseases or other health problems may need more treatment for chicken pox. They may need immunoglobulin treatment (IG) or antiviral medicine. Your doctor can give you these soon after you are exposed to the virus to help you feel better sooner.
How can you prevent chicken pox?
You can prevent chicken pox by getting the chicken pox (varicella) vaccine. The Public Health Agency of Canada recommends one dose of this shot for healthy children 12 months of age and older who have not had chicken pox. Older children and adults who have not had chicken pox and have not yet had the vaccine need two doses.
Most children do not have a reaction from the vaccine. But if your child has a serious or long-term illness, talk to your doctor about whether your child should have the vaccine. These children may have a bad reaction from the vaccine.
If you have been around a person who has the virus and you have not had chicken pox or the vaccine, you still may be able to prevent the illness. Get a shot of chicken pox antibodies or the vaccine right away.
In rare cases, people who have had the vaccine still get chicken pox. And a few people who have already had chicken pox get it again. If this happens, a milder form of the illness usually occurs, with fewer blisters and symptoms. This is called a breakthrough infection.
Do not expose your child to chicken pox on purpose. Some parents expose their children to chicken pox because they think it is safer for children to have the illness when they are young. But this isn't a good idea, because even young children can have serious problems from chicken pox.
Frequently Asked Questions
Learning about chicken pox:
Being diagnosed:
Getting treatment:
Ongoing concerns:
Taking care of yourself:
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| Author: | Debby Golonka, MPH Ralph Poore | Last Updated: May 30, 2008 |
| Medical Review: | Adam Husney, MD - Family Medicine Michael J. Sexton, MD - Pediatrics Thomas Emmett Francoeur, MDCM, CSPQ, FRCPC - Pediatrics | |
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