Introduction
Chickenpox may be remembered as a common childhood illness, but it is not always harmless. The infection can cause an itchy blistering rash, fever, tiredness, and loss of appetite, and some people can develop more serious complications. Adolescents, adults, pregnant women, infants, and people with weakened immune systems are among those who can face a higher risk of severe illness.
The chicken pox vaccine, also called the varicella vaccine, provides a way to develop protection without going through natural chickenpox infection. In the United States, routine vaccination consists of two doses for children, while older children, adolescents, and adults who lack evidence of immunity generally need two doses as well.
Understanding when the vaccine is given, who should avoid it, possible reactions, and what to do after exposure can help families make informed vaccination decisions.
What Is the Chicken Pox Vaccine?
The chicken pox vaccine is a vaccine designed to prevent varicella, the viral infection commonly known as chickenpox.
The vaccine contains a weakened form of varicella-zoster virus. It stimulates the immune system so the body can recognize and respond to the virus without experiencing the typical illness caused by natural infection.
Two varicella-containing vaccines are licensed in the United States:
- Varivax, which contains varicella vaccine alone
- ProQuad, which combines measles, mumps, rubella, and varicella vaccines and is known as MMRV
MMRV is licensed for children from 12 months through 12 years of age.
Why Is the Chicken Pox Vaccine Important?
Chickenpox is often mild in healthy children, but there is no reliable way to predict who will develop complications.
Possible complications of chickenpox include:
- Bacterial skin infections
- Pneumonia
- Inflammation involving the brain
- Inflammation involving tissues around the brain and spinal cord
- Bloodstream infections
- Bone or joint infections
The infection can be particularly concerning in infants, adolescents, adults, pregnant women, and people with weakened immune systems.
Vaccination reduces the chance of developing chickenpox and greatly lowers the risk of severe disease.
Chicken Pox Vaccine Schedule for Children
Children are routinely recommended to receive two doses of varicella vaccine.
The usual schedule is:
- First dose: 12 through 15 months
- Second dose: 4 through 6 years
The vaccine can be administered at the same visit as other recommended childhood vaccines.
For certain children, healthcare professionals may use the combined MMRV vaccine rather than giving separate measles, mumps, rubella, and varicella vaccines.
What If a Child Misses a Dose?
Missing the recommended date does not normally mean that the vaccination series needs to be restarted.
A healthcare professional can review the child’s vaccination record and determine when the next dose should be given.
Keeping vaccination records is helpful because it allows healthcare providers to determine whether a child has already received adequate protection.
Chicken Pox Vaccine for Teenagers and Adults
People who reach adolescence or adulthood without evidence of immunity may still need vaccination.
CDC guidance recommends that people aged 13 years and older who have never had chickenpox or received the vaccine receive two doses, with the doses separated by at least 28 days.
This is particularly relevant for people who:
- Never had chickenpox
- Were never vaccinated
- Work in healthcare
- Work with young children
- Live with people who have weakened immune systems
- Attend college
- Travel internationally
- Work in settings where exposure may be more likely
Adults should discuss their individual vaccination history with a healthcare professional if their immunity is uncertain.
Can Adults Get the Chicken Pox Vaccine?
Yes.
Adults who do not have evidence of immunity can be vaccinated. CDC guidance recommends two doses for adults who have never had chickenpox or vaccination, with the doses at least 28 days apart.
Adults who are unsure whether they received the vaccine or had chickenpox should discuss their history with a healthcare provider. Depending on the circumstances, documentation or laboratory evidence may help determine immunity.
How Effective Is the Chicken Pox Vaccine?
Two doses provide strong protection against chickenpox vaccine.
CDC states that two doses are about 90% effective at preventing chickenpox. Vaccinated people who do develop so-called breakthrough chickenpox generally experience a milder illness, often with fewer blisters and less fever.
No vaccine provides perfect protection for every person, but vaccination substantially reduces the likelihood of serious disease.
How Long Does Chicken Pox Vaccine Protection Last?
Available evidence indicates that most people who receive two doses are protected for a very long time, and CDC states that most vaccinated people are protected for life.
Routine booster doses are not generally part of the standard two-dose childhood schedule.
Chicken Pox Vaccine After Exposure
What happens after exposure depends on whether the person is already immune and whether vaccination is appropriate.
For someone without immunity who has recently been exposed to chickenpox, vaccination after exposure may prevent the illness or make it less severe.
However, not everyone who is exposed can receive the vaccine. For example, pregnancy and certain immune-system conditions can make live vaccines inappropriate.
A healthcare professional should be contacted promptly after a significant exposure, especially if the exposed person is pregnant, immunocompromised, an infant, or otherwise at high risk.
Can You Get Chickenpox After Vaccination?
It is possible, but it is less likely.
A small number of vaccinated people develop breakthrough chickenpox after exposure to the virus. When it happens, the illness is generally milder than chickenpox in an unvaccinated person.
A vaccinated person may have fewer skin lesions, little or no fever, and a shorter or less intense illness.
Chicken Pox Vaccine Side Effects
Most people tolerate the vaccine well.
Possible reactions can include:
- Soreness where the injection was given
- Redness
- Swelling
- Fever
- Mild rash
These reactions are generally mild and temporary.
A vaccine can occasionally cause more serious reactions, although serious adverse events are uncommon.
If someone develops signs of a severe allergic reaction after vaccination, emergency medical attention is necessary.
Does the Chicken Pox Vaccine Cause Chickenpox?
The vaccine uses a weakened form of the virus rather than the disease-causing form found in natural infection.
Some vaccinated people can develop a mild rash, but this is not the same as experiencing typical natural chickenpox.
The purpose of vaccination is to train the immune system to recognize varicella and respond more effectively.
Who Should Not Get the Chicken Pox Vaccine?
Because varicella vaccine is a live attenuated vaccine, certain people should not receive it.
Important situations include:
- Pregnancy
- Severe immune-system problems
- Certain cancers or cancer treatments
- Certain immunosuppressive medications
- A previous severe allergic reaction to the vaccine or one of its components
CDC specifically identifies pregnancy and severe immunocompromising conditions as reasons not to receive varicella vaccine.
People should not make this decision based solely on an online article. A healthcare professional can determine whether vaccination is appropriate based on medical history.
Chicken Pox Vaccine During Pregnancy
The chickenpox vaccine should not be given during pregnancy because it is a live attenuated vaccine.
People who are not immune and are planning pregnancy should discuss vaccination with their healthcare provider beforehand.
CDC guidance states that people vaccinated against varicella should avoid becoming pregnant for one month after each injection.
If someone accidentally receives varicella vaccine while pregnant, this is not considered a reason to terminate the pregnancy, but the person should inform their healthcare provider.
Can You Get the Vaccine While Breastfeeding?
Pregnancy and breastfeeding are different situations.
CDC guidance indicates that varicella vaccination can be given postpartum, including after delivery. People who were not immune during pregnancy may be recommended to receive the vaccine after pregnancy.
A healthcare professional can advise on the appropriate schedule based on previous doses and immunity.
What About People With Weak Immune Systems?
Extra caution is necessary.
Some people with immune-system problems may be unable to safely receive live vaccines. Others may be eligible under specific circumstances.
For example, CDC provides specific considerations for certain people with HIV and emphasizes that vaccination decisions depend on immune status.
Anyone receiving chemotherapy, significant immunosuppressive treatment, or treatment affecting immune function should discuss varicella vaccination with their healthcare team before receiving a dose.
Chicken Pox Vaccine and Healthcare Workers
Healthcare professionals can be exposed to varicella and may also encounter patients who are especially vulnerable to infection.
CDC recommends varicella vaccination for healthcare personnel who do not have evidence of immunity.
This helps protect both healthcare workers and vulnerable patients.
Can the Chicken Pox Vaccine Be Given With Other Vaccines?
Yes, varicella vaccine can be administered at the same time as certain other vaccines.
For children, MMRV combines protection against:
- Measles
- Mumps
- Rubella
- Varicella
The healthcare provider can determine whether a combination vaccine or separate vaccines are appropriate for a particular child.
What Should You Tell Your Doctor Before Vaccination?
Before receiving a chickenpox vaccine, tell your healthcare provider about:
- Previous vaccine reactions
- Severe allergies
- Pregnancy or plans for pregnancy
- Immune-system conditions
- Cancer
- Current medications
- Recent blood products or transfusions
- Previous chickenpox vaccination
- A history of chickenpox or shingles
This information helps the provider determine whether the vaccine is appropriate and whether timing needs to be adjusted.
Chicken Pox Vaccine vs Natural Infection
Some people believe that getting chickenpox naturally is preferable to vaccination because it creates immunity.
This approach carries an unnecessary risk.
Natural chickenpox can cause serious complications, hospitalization, and, rarely, death. Vaccination allows the immune system to develop protection without exposing someone to the full risks of natural infection.
For this reason, vaccination is the safer route to protection for people who are eligible.
What Happens After the Vaccine?
Most people can continue their normal activities after vaccination.
Mild soreness, redness, swelling, fever, or a mild rash can occur. If symptoms are unusually severe or concerning, medical advice should be sought.
Following the vaccination schedule is important because the second dose provides additional protection for people who need the complete two-dose series.
Why Vaccination Also Protects the Community
Vaccination does more than protect the individual who receives it.
When fewer people become infected, there are fewer opportunities for the virus to circulate and reach people who cannot be vaccinated or who are particularly vulnerable to complications.
This is especially important in households, schools, childcare settings, healthcare facilities, and communities where many people are in close contact.
Conclusion
The chicken pox vaccine is an effective way to reduce the risk of varicella and its potentially serious complications. CDC recommends two doses for children, with the first typically given at 12–15 months and the second at 4–6 years. Older children, adolescents, and adults without evidence of immunity generally need two doses as well.
Most vaccine reactions are mild, such as soreness, redness, swelling, fever, or a mild rash. However, varicella vaccination is not suitable for everyone. Pregnancy and certain immune-system conditions require special attention because the vaccine is live attenuated.
If you are unsure whether you or your child needs a chickenpox vaccine, reviewing the vaccination record and medical history with a qualified healthcare professional is the safest approach.
FAQs About Chicken Pox Vaccine
1. What is the chicken pox vaccine?
The chicken pox vaccine, also called the varicella vaccine, protects against varicella, the virus that causes chickenpox.
2. How many doses of chickenpox vaccine are needed?
Children generally receive two doses: the first at 12–15 months and the second at 4–6 years. Older children and adults without immunity generally need two doses separated by at least 28 days.
3. Can adults get the chicken pox vaccine?
Yes. Adults who have never had chickenpox or received the vaccine and lack evidence of immunity can receive a two-dose series.
4. Is the chicken pox vaccine safe?
The vaccine is considered safe and most side effects are mild. Common reactions include soreness, redness, swelling, fever, and mild rash.
5. Can you get chickenpox after being vaccinated?
Yes, breakthrough infection can occur, but vaccinated people who develop chickenpox usually have a milder illness than unvaccinated people.
6. Can pregnant women get the chicken pox vaccine?
No. Varicella vaccine is contraindicated during pregnancy. People without immunity should discuss vaccination before pregnancy or after delivery.
7. Can the vaccine be given after exposure to chickenpox?
In some situations, vaccination after exposure can prevent chickenpox or make the illness less severe. A healthcare professional should determine whether vaccination is appropriate.
8. How effective is the chicken pox vaccine?
Two doses are about 90% effective at preventing chickenpox, according to CDC information.
9. What are the common side effects of the chickenpox vaccine?
Soreness, redness, swelling at the injection site, fever, and a mild rash are among the possible side effects.
10. Who should talk to a doctor before getting the vaccine?
Anyone who is pregnant, has a weakened immune system, has certain medical conditions, takes immune-suppressing medicines, or has experienced a severe allergic reaction to a previous dose or vaccine component should speak with a healthcare professional before vaccination.
