What causes chickenpox?
Chickenpox is caused by a virus, the varicella-zoster virus.
How does chickenpox spread?
How long does it take to show signs of chickenpox after being exposed?
It takes from 10-21 days to develop symptoms after being exposed to a person infected with chickenpox. The usual time period is 14-16 days.
What are the symptoms of chickenpox?
How serious is chickenpox?
What are possible complications from chickenpox?
How do I know if my child has chickenpox?
How long is a person with chickenpox contagious?
Is there a treatment for chickenpox?
Chickenpox may be treated with an antiviral drug in serious cases, depending on the patient's age and health, the extent of the infection, and the timing of the treatment.
How common is chickenpox in the
Because it is so easy to catch chickenpox, almost every adult in the
Can you get chickenpox more than once?
If I think my child has been exposed to chickenpox, what should I do?
If the child has had chickenpox or has been vaccinated, nothing needs to be done. It is recommended that a susceptible person (one who has never had chickenpox) receive the chickenpox vaccine as soon as possible after being exposed to the virus. There is evidence that the vaccine may prevent illness or reduce the seriousness of the disease, if given within 3 to 5 days following exposure. Even if the person was not infected with the chickenpox virus from the exposure, receiving the vaccination will prevent future disease.
How are chickenpox and shingles related?
When did the chickenpox vaccine become available?
The chickenpox (varicella) vaccine was licensed for use in
What kind of vaccine is it?
The chickenpox vaccine is a live attenuated vaccine. This means the live, disease-producing virus was modified, or weakened, in the laboratory to produce an organism that can grow and produce immunity in the body without causing illness.
How is this vaccine administered?
The chickenpox vaccine is a shot, given in the fatty tissue.
Who should get this vaccine?
Chickenpox vaccine is recommended for the following:
· All children younger than age 13 years (one dose at 12-15 months and a second dose at age 4-6 years);
· Everyone age 13 years and older who has never had chickenpox (two doses, given 4-8 weeks apart);
Anyone missing a dose at the recommended times should get the shot at their next visit to their doctor or clinic.
Who recommends this vaccine?
The Centers for Disease Control and Prevention (CDC), the
Should adults be tested before vaccination to see if they are already immune to chickenpox?
Currently, 90% of adults are immune to chickenpox because of having had the disease as children. If you have a history of chickenpox disease, you don’t need testing or vaccination, unless you are working in an environment where your immune status must be documented (such as a hospital). If you are uncertain of your medical history, blood testing can be done to see if immunization is appropriate.
How safe is this vaccine?
Tens of millions of doses of varicella vaccine have been given in the
What side effects have been reported with this vaccine?
Possible side effects are generally mild and include redness, stiffness, and soreness at the injection site; such localized reactions occur in about 20% of children immunized. A small percentage of persons develop a mild rash, usually around the spot where the shot was given.
How effective is this vaccine?
Ninety-seven percent of children between age 12 months and 12 years develop immunity to the disease after one dose of vaccine. For older children and adults, an average of 78% develop immunity after one dose and 99% develop immunity after the recommended two doses.
Although some vaccinated children (about 2%) will still get chickenpox, they generally will have a much milder form of the disease, with fewer blisters (typically fewer than 50), lower fever, and a more rapid recovery.
The vaccine almost always prevents against severe disease. Getting chickenpox vaccine is much safer than getting chickenpox disease.
Isn’t it better for a child to get chickenpox naturally?
Some parents purposely seek to get their children infected with varicella virus, even promoting “chickenpox parties” for this purpose. The belief is that it’s better to be infected when young, a time when the infection is ordinarily less severe. Some parents also believe that something “natural” (the disease) is better than something “artificial” (the vaccine), or that immunity derived from the disease will be more permanent than that from the vaccine.
However, when a safe vaccine is available, parents need to weigh the supposed benefits of infection against its potential risks, including severe disease with complications such as infection with flesh-eating bacteria. No one can predict which child will develop a life-threatening case of chickenpox; in fact, most serious cases occur in previously healthy children.
In addition, in a recent study, 7 out of 10 children said given the choice, they’d rather have the shot than have the natural disease.
Can the vaccine protect you if you’ve already been exposed to chickenpox?
Yes, it is 70-100% effective if given within 72 hours of exposure.
Who should NOT receive the chickenpox vaccine?
Persons with weakened immune systems and those with life-threatening allergies to gelatin or the antibiotic neomycin should not receive this vaccine.
Pregnant women should not receive this vaccine, as the possible effects on fetal development are unknown. However, non-pregnant women of childbearing age who have never had the disease may be immunized against chickenpox to avoid contracting the disease while pregnant.
Can the vaccine cause chickenpox?
Because this vaccine is made from a live, but weakened, virus, about 1% of recipients develop a mild form of the disease, consisting of a limited rash, most often with only 5-6 blisters. Usually there is no fever. These persons are then safe from the more serious, naturally occurring form of the virus.
Can the varicella vaccine virus be transmitted (caught) from a person who was vaccinated?
Yes; however, transmission of the varicella vaccine virus is extremely rare. It has only been documented in healthy persons on three occasions out of the 21 million doses of vaccine distributed. All three cases resulted in mild disease without complications.
Can the vaccine cause herpes zoster (shingles)?
Yes, this is possible. The risk of zoster following vaccination appears to be less than that following infection with the varicella virus. The majority of cases of shingles following vaccination have been mild and have not been associated with serious complications.
Technically reviewed by the Centers for Disease Control and Prevention, February 2007.
This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have this infection, consult a health care provider.
Content Last Modified on 1/29/2009 4:53:35 PM