Chickenpox is a highly contagious disease caused by the varicella-zoster virus (VZV). It can cause an itchy, blister-like rash among other symptoms. The rash first appears on the chest, back, and face, and then spreads over the entire body.
Chickenpox can be serious, especially during pregnancy, in babies, adolescents, adults, and people with weakened immune systems (lowered ability to fight germs and sickness).
The best way to prevent chickenpox is to get the chickenpox vaccine.
A person with chickenpox is considered contagious beginning 1 to 2 days before rash onset until all the chickenpox lesions have crusted (scabbed). Vaccinated people who get chickenpox may develop lesions that do not crust. These people are considered contagious until no new lesions have appeared for 24 hours.
Signs and Symptoms
Anyone who has not had chickenpox or gotten the chickenpox vaccine can get the disease. Chickenpox illness usually lasts about 4 to 7 days.
The classic symptom of chickenpox is a rash that turns into itchy, fluid-filled blisters that eventually turn into scabs. The rash may first show up on the chest, back, and face, and then spread over the entire body, including inside the mouth, eyelids, or genital area. It usually takes about one week for all of the blisters to become scabs.
Other typical symptoms that may begin to appear one to two days before rash include:
- fever
- tiredness
- loss of appetite
- headache
Children usually miss 5 to 6 days of school or childcare due to chickenpox.
When to Call a Healthcare Provider
For people exposed to chickenpox or shingles, call a healthcare provider if the person:
- Has never had chickenpox and is not vaccinated with the chickenpox vaccine
- Is pregnant
- Has a lowered ability to fight germs and sickness (weakened immune system) caused by disease or medication; for example:
- A person with HIV/AIDS or cancer
- A person who has had a transplant
- A person on chemotherapy, immunosuppressive medications, or long-term use of steroids
If you have symptoms, call your healthcare provider. Contacting a healthcare provider is especially important if the person:
Is at risk of serious complications from chickenpox because they:
- Are less than 1 year old
- Are older than 12 years of age
- Have a weakened immune system
- Are pregnant
OR
Develops any of the following symptoms:
- Fever that lasts longer than 4 days
- Fever that rises above 102°f (38.9°c)
- Any areas of the rash or any part of the body becomes very red, warm, or tender, or begins leaking pus (thick, discolored fluid), as these symptoms may indicate a bacterial infection
- Difficulty waking up or confused behavior
- Difficulty walking
- Stiff neck
- Frequent vomiting
- Difficulty breathing
- Severe cough
- Severe abdominal pain
- Rash with bleeding or bruising (hemorrhagic rash)