varicella-zoster virus (live) at a glance
Medicine class
Live attenuated viral vaccine
Main purpose
Prevention of chickenpox in susceptible people
Administration
Injection into a muscle or under the skin by a trained healthcare professional
Important screening
Pregnancy, immune suppression and serious allergy to vaccine components must be checked before vaccination
What is varicella-zoster virus (live) used for?
Licensed uses of the selected product include:
Vaccination against chickenpox from 12 months of age.
Vaccination from 9 months of age in special circumstances, such as an outbreak or where official recommendations support it.
Vaccination of susceptible people after exposure to chickenpox, where timely administration may prevent infection or make it milder.
How does varicella-zoster virus (live) work?
The weakened virus replicates to a limited extent and exposes the immune system to varicella antigens. This produces antibodies and immune memory that can respond more rapidly to later contact with the natural virus. Protection is not guaranteed in every recipient.
How to take varicella-zoster virus (live)
The vaccine is prepared and given by a healthcare professional.
It may be injected into a muscle or under the skin.
People with thrombocytopenia or a coagulation disorder should receive it under the skin.
It must not be injected into a blood vessel or mixed with another medicine in the same syringe.
Tell the vaccinator about pregnancy, illness, immune problems, allergies, recent blood products and other vaccinations.
varicella-zoster virus (live) side effects
Common or expected effects
- Pain, redness or swelling where the injection was given
- Fever
- A mild local or more widespread varicella-like rash
- Itching or irritability
Get urgent medical advice
- Severe allergic reaction, including facial or throat swelling and breathing difficulty
- Seizure, reduced consciousness or symptoms suggesting encephalitis
- Severe blistering skin reaction or secondary skin infection
- Pneumonia, meningitis or disseminated vaccine-strain infection, reported rarely, particularly where immune function is impaired
varicella-zoster virus (live) in pregnancy
VARIVAX is contraindicated during pregnancy, and pregnancy should be avoided for one month afterwards. If vaccination occurred shortly before or during pregnancy, contact the maternity team or prescriber. UK surveillance is reassuring and has not identified a specific fetal risk, but the exposure should be reported to UKHSA surveillance.
varicella-zoster virus (live) while breastfeeding
The VARIVAX product information does not generally recommend use during breastfeeding because transmission of vaccine virus is theoretically possible. UK specialist guidance considers live vaccines other than yellow fever vaccine compatible with breastfeeding; the prescriber should assess individual circumstances and product-specific precautions.
varicella-zoster virus (live) interactions
Tell the vaccinator about all medicines, vaccines and blood products received recently or planned.
Immunosuppressive treatment, including high-dose corticosteroids
May cause serious infection or an inadequate response. Significant immunosuppression is a contraindication and specialist assessment may be required.
Immunoglobulins, varicella-zoster immunoglobulin, blood or plasma products
Varicella antibodies can neutralise the vaccine virus and reduce the immune response, so vaccination timing must be reviewed.
Other live viral vaccines, including MMR
They may be given at separate sites during the same visit; otherwise the vaccinator must arrange appropriate separation.
Common questions about varicella-zoster virus (live)
Answers are fully visible for fast scanning and source review.
Is varicella-zoster virus (live) the chickenpox vaccine?
Yes. It is a live attenuated vaccine used to develop immunity against chickenpox.
Can it cause chickenpox?
A mild varicella-like rash can occur. Serious or disseminated vaccine-strain infection is rare and is a particular concern in people with impaired immunity.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.