What is chickenpox (varicella)?
Chickenpox is a highly contagious disease caused by the varicella-zoster virus. People with chickenpox develop a rash that turns into itchy, fluid-filled blisters which turn into scabs. The rash commonly shows up on the chest, back, and face, and spreads across the entire body. Some people develop serious complications from chickenpox which can lead to hospitalization or death.
After causing chickenpox, the varicella zoster virus stays in the body and may cause shingles later in life. People with shingles can transmit the virus to other people.
What are the symptoms of chickenpox?
- Early symptoms of chickenpox include:
- Fever.
- Tiredness.
- Loss of appetite.
- Headache.
One to two days after symptoms start, people develop a rash which may start on the chest, back, and face. The rash spreads across the entire body. The rash turns into itchy, fluid filled blisters that eventually scab. It takes about one week for all blisters to scab.
Severe complications from chickenpox are uncommon, but can lead to:
- Bacterial infections.
- Infections of the lungs (pneumonia) or brain (encephalitis).
- Bleeding problems or bloodstream infections.
- Dehydration.
Is chickenpox contagious?
Chickenpox is highly contagious and is spread by direct contact with fluids from blisters or by breathing in virus particles that come from blisters. Up to 90% of people in close contact with someone with chickenpox will get it if they have not been vaccinated. A person with chickenpox is contagious 1 to 2 days before forming a rash and until all lesions have scabbed over.
How can we prevent chickenpox?
Varicella vaccination is the strongest protection against chickenpox. Children normally receive a dose of varicella vaccine at 12 to 15 months of age and again at 4 to 6 years of age.
Varicella vaccine can prevent or reduce the severity of chickenpox. Two doses of chickenpox vaccine are more than 90% effective at preventing the disease. People who are vaccinated and get sick with chickenpox will have less severe symptoms, such as few or no blisters, mild or no fever, and quicker recovery from the illness.
If someone has symptoms like chickenpox, they should call their healthcare provider right away. Avoid contact with family members or other people who have not been vaccinated, as chickenpox spreads very easily. Wash bed linens and bath towels used by the infected person often, and make sure everyone washes their hands frequently with soap and water.
For more information about chickenpox vaccination, visit our chickenpox vaccine page.
Chickenpox Vaccine Requirements
Washington state requires children entering childcare, kindergarten, or grade school to be vaccinated against chickenpox (varicella). You can read more about this requirement on our school and childcare immunizations information webpage.
Chickenpox Activity and Surveillance
Death from varicella is a notifiable condition in Washington state. View the Notifiable Conditions page for details on reporting.