Chicken pox Overview

What is chickenpox? What causes chickenpox?

Chickenpox is a common childhood skin disease caused by a virus. The virus is called the varicella-zoster virus.

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 the sores have crusted over, the person is usually no longer contagious.

What are the signs and symptoms of chickenpox?

Symptoms tend to appear 14 to 16 days after the initial exposure but can occur any time from 10 days up to 21 days after contact with the virus. Chickenpox is characterized by one to two days of mild fever up to 102 degrees F, general weakness, and a rash, often the first sign of the disease. Rarely, a person may have the disease without the rash. The rash of chickenpox develops in crops with raised red spots arriving first, progressing to blisters that burst, creating open sores, before crusting over. This process usually starts on the scalp, then the trunk (its area of greatest concentration), and finally the arms and legs. Any area of skin that is irritated (by diaper rash, poison ivy, eczema, sunburn, etc.) is likely to be hard hit by the rash. The rash is typically very itchy (pruritic).