Introduction
Varicella, also called chickenpox, is a very contagious disease caused by a virus.
It can cause an itchy rash with blisters, fever, and tiredness. Most cases are mild, but some people can get very sick.
Before the vaccine was made available in 1995, chickenpox was very common in the United States. Each year, about 4 million people got chickenpox, and many were hospitalized.
Today, vaccination has reduced chickenpox cases by more than 97% in the U.S.
How Chickenpox Spreads & Who is Affected
Chickenpox spreads very easily from person to person.
It spreads through:
- The air (when someone coughs or sneezes)
- Touching the fluid from blisters on people who are infected
A person can spread chickenpox:
- From 2 days before the rash starts until the blisters crust over
People at higher risk for serious illness include:
- People with weak immune systems
Outbreaks of chickenpox and other vaccine-preventable diseases are more likely to happen in child care facilities and schools with low vaccination coverage among students. Look up vaccination rates:
Child Care/Preschool | Kindergarten and 7th Grade
Symptoms & Health Effects
Symptoms usually start 10 to 21 days after exposure.
Common symptoms include:
- Itchy rash that turns into blisters, then scabs
People with chickenpox may get as many as 250-500 blisters. Chickenpox can sometimes lead to serious health problems, such as:
- Skin infections and scarring
- Pneumonia (lung infection)
- Brain infection or swelling
After a person has chickenpox, the virus stays in the body and can come back later as shingles, a painful rash.
Prevention
Vaccination is the best way to prevent chickenpox.
Other ways to help stop the spread:
- Avoid close contact with others
High vaccination rates help protect schools and communities from outbreaks.
Chickenpox Vaccination
The chickenpox vaccine protects against infection and is recommended for all children who have not had the disease. Most people who get the vaccine are protected for life and won't get chickenpox. People who get the chickenpox vaccine are also less likely to get shingles than those who had the natural infection.
Recommended schedule:
Older children who haven't had chickenpox infection or the vaccine should get vaccinated.
Who Should Get Vaccinated
The vaccine is recommended for:
- Teens who have not had chickenpox or the vaccine
Some people should talk to a doctor before getting vaccinated, such as:
- People with weak immune systems
Safety & Effectiveness
- How well does the vaccine work? After getting both doses, about 9-10 out of 10 people are protected. Almost all severe cases are prevented.
- Chickenpox vaccine has been used for many years and is very safe. The vaccine may cause:
- Soreness where the shot was given (about 1 in 5 people)
- Fever (up to 1 in 10 people), or
- A mild rash (up to 6 in 100 people)
- Serious side effects are very rare (less than 1 in 1 million doses) but may include severe allergic reactions or fever-related seizures.
What to Do if You Are Exposed to Chickenpox
If you are not protected and are exposed:
- Get the vaccine within 3 to 5 days, if possible, to prevent illness or reduce its severity
Some people may need medication to prevent illness.
Additional Tips
- When sick, stay home and do not go to school or work until all blisters are crusted. Avoid close contact with babies, pregnant people, and people with weak immune systems. Also keep fingernails short and clean to help prevent skin infections from scratching.
- Check vaccine records to make sure your family is up to date.
- Plan ahead for school to meet vaccine requirements.
- Find clinics offering chickenpox vaccination in your area on My Turn.
- The vaccine can be given at the same visit as other routine vaccinations.