Caused by the varicella-zoster virus (VZV), chickenpox used to be a common illness among kids in the United States (particularly among those under age 12). An itchy rash of spots that look like blisters can appear all over the body and be accompanied by flu-like symptoms. Chickenpox is very contagious, so an infected child should stay home and rest until the rash is gone.
Chickenpox often starts with a fever, headache, sore throat, or stomach ache. These symptoms may last for a few days, with fever in the 101°-102°F (38.3°-38.8°C) range.
Chickenpox causes a red, itchy skin rash that usually appears first on the abdomen or back and face, and then spreads to almost everywhere else on the body, including the scalp, mouth, arms, legs, and genitals.
The rash begins as multiple small red bumps that look like pimples or insect bites, usually less than a quarter of an inch wide. They appear in crops over 2 to 4 days and develop into thin-walled blisters filled with fluid. The blister walls break, leaving open sores, which finally crust over to become dry, brown scabs. The rash is very itchy, and cool baths or calamine lotion may help to manage the itching.
A hallmark of chickenpox is that all stages (red bumps, blisters, and scabs) can appear on the body at the same time. The rash may be more extensive or severe in kids who have skin disorders like eczema, or weak immune systems. Young kids tend to have a mild illness with fewer blisters than older children or adults.
In rare cases, serious bacterial infections involving the skin, lungs, bones, joints, and the brain can occur.