Chickenpox
(Varicella)

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What is chickenpox? What causes chickenpox?

Chickenpox is a common childhood skin disease caused by a viral infection. The virus involved is called the varicella-zoster virus. Today, chickenpox is less common in the United States due to universal vaccination with the varicella virus vaccine, though it still occurs in populations that are not routinely vaccinated. Varicella-zoster virus is often categorized with the other common so-called "viral exanthems" (viral rashes) such as measles (rubeola), German measles (rubella), fifth disease (parvovirus B19), mumps virus, and roseola (human herpesvirus 6), but these viruses are unrelated except for their tendency to cause rashes.

In unimmunized populations, most people contract chickenpox by age 15, the majority between ages 5 and 9, but all ages can contract it. Chickenpox is usually more severe in adults and very young infants than children. Winter and spring are the most common times of the year for chickenpox to occur.

How does chickenpox spread?

Chickenpox is very highly contagious. It is easily passed between members of families and school classmates through airborne particles, droplets in exhaled air, and fluid from the blisters or sores. It also can be transmitted indirectly by contact with articles of clothing and other items exposed to fresh drainage from open sores. Patients are contagious up to five days (more commonly, one to two days) before and five days after the date that their rash appears. When all of the sores have crusted over, the person is usually no longer contagious.



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Chickenpox (Varicella) - Side Effects Question: Did your child experience any side effects from the chickenpox vaccine?
Chickenpox - Adult Experience Question: Please describe your experience with being infected with chickenpox as an adult.
Learn about signs, symptoms and complications of chickenpox.

Chickenpox Vaccine for My Child?

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

My children were not vaccinated against chickenpox. When they were young, we were living in Europe, where the medical community does not encourage immunization against this disease. Consequently, my kids developed chickenpox at an early age, during one month in which over 30 children in our neighborhood became infected.

I had, in fact, planned to have the children immunized for chickenpox on our next visit to the U.S., but the infection came before that happened. My oldest child, who was 4 at the time, contracted chickenpox from a friend at preschool. He hardly suffered at all; there were perhaps only 20 or 25 skin lesions in total. Not so for my youngest two children, then aged 2 and a half and 16 months. Because their exposure came from their older brother at home ("prolonged" exposures in the home can lead to more severe disease than casual or onetime exposures) they were both covered from head to toe with the itchy spots. Even the membranes of their mouths and eyes were affected, and they were listless with fever. While no serious complications developed, they were decidedly miserable and uncomfortable for days.

Living in Europe and talking with other parents, I encountered a good bit of skepticism about the chickenpox vaccine in use in the U.S. While hardly anyone considered the vaccine to be dangerous, most felt it wasn't necessary to vaccinate a child against what they perceived to be a "harmless" disease that even "strengthened" their child's immune system.

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