Conditions InDepth: Chickenpox
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Chickenpox is a highly contagious viral infection. It produces a widespread itchy rash with blisters and crusting. The varicella zoster virus (VZV) causes chickenpox. The virus can spread from person to person via:
- Airborne droplets of moisture containing the virus
- Direct contact with fluid from a chickenpox rash
The virus is most contagious for 1-2 days before the rash erupts and during the first day or so after the rash has broken out. It remains contagious until all of the blisters have crusted.
Because of an extensive
program, the incidence of chickenpox has declined greatly in the United States. The majority of cases occur in infants, children, and adolescents under age 12. The incidence among adults 20 years or older is very low. When contracted during childhood, chickenpox is usually not serious. Serious complications are more common when contracted by adolescents, adults, newborns, or people with a suppressed immune system. These complications can include:
What are the risk factors for chickenpox?What are the symptoms of chickenpox?How is chickenpox diagnosed?What are the treatments for chickenpox?Are there screening tests for chickenpox?How can I reduce my risk of chickenpox?What questions should I ask my doctor?Where can I get more information about chickenpox?
Pneumonia—usually in adults or older children
Central nervous system complications, including:
Bacterial infections from Group A streptococci and
leading to infections in the skin, bones, or joints,
toxic shock syndrome, bacteremia, arteritis,
- Bleeding problems due to low platelet counts
- Eye of optic nerve damage
- If a susceptible mother catches chickenpox while pregnant, damage to the baby may occasionally result. Some associated birth defects include: poor growth of arms or legs, skin scarring, small head, and perhaps intellectual disability or other abnormalities of the nervous system
is a complication of chickenpox that can occur years later.
Chickenpox. American Academy of Family Physicians Family Doctor website. Available at:
Updated May 2010. Accessed February 29, 2016.
Chickenpox. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T116084/Chickenpox. Updated September 8, 2015. Accessed October 3, 2016.
Chickenpox (varicella). Centers for Disease Control and Prevention website. Available at:
Updated November 18, 2014. Accessed February 29, 2016.
EBSCO Medical Review BoardMichael Woods, MD
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