Chickenpox is an infectious disease caused by the varicella zoster virus (VZV), a virus that is part of the herpes virus family. The illness results in a blister-like rash, itching, tiredness, and fever.
Before the introduction of the
varicella vaccine in 1995, approximately 4 million cases of chickenpox were reported annually, including 4,000 to 9,000 hospitalizations and 100 deaths. Since the introduction of the vaccine, the number of cases has dropped dramatically.
Symptoms of chickenpox can begin with 1 to 2 days of low-grade fever and tiredness. These early symptoms do not always occur before the chickenpox rash develops.
Early symptoms are followed by itchy blisters that first appear on the trunk, face, and scalp. These blisters can spread over the entire body, causing between 250 and 500 itchy blisters. The chickenpox rash can appear in three or more successive waves. Eventually, the blisters crust over.
Treatment Options for Chickenpox
In most cases, chickenpox can be treated at home. Home treatment involves relieving symptoms as the body fights the virus. It is important to regularly look at the skin and to make sure that the blisters are not becoming infected. It is also important to monitor other symptoms, such as fever.
If a person experiences more serious symptoms of chickenpox, a visit to the doctor may be necessary. Some of these more serious symptoms include:
(Click Treatment for Chickenpox for more information.)
About 1 in 10 children who first have chickenpox symptoms will have a complication that is serious enough to require a visit to a healthcare provider.
Most complications of chickenpox are caused by an infection from bacteria. These bacteria can cause complications such as:
- Skin or soft tissue infections
- Pneumonia (usually more severe in adults and in children over 13 years old)
- Bone infections (osteomyelitis)
- Joint infections (septic arthritis)
- Toxic shock syndrome.
Other serious complications directly related to the chickenpox virus can include:
- Infection of the brain (encephalitis)
- Bleeding problems
- Cerebellar ataxia.
Chickenpox transmission occurs via direct contact with someone infected with the virus or through the air from an infected person's coughing or sneezing. Less commonly, transmission can occur when someone comes into direct contact with a person who has an active
herpes zoster (
shingles) infection.
A person with chickenpox is contagious 1-2 days before the rash appears and until all blisters have formed scabs.
The usual incubation period is 14-16 days (ranging between 10-21 days).
Is There a Vaccine for Chickenpox?
In 1995, the Food and Drug Administration approved the
varicella vaccine, also known as the
chickenpox vaccine, for the prevention of chickenpox. The vaccine is now widely available in private doctors' offices and public health clinics.
The vaccine is the best way to prevent chickenpox, therefore protecting children and adults from the severe complications (including death) that can occur with this illness.
