Live varicella virus vaccine: what to know

The vaccine presents the immune system with a weakened varicella virus so it can build protective recognition without the usual illness caused by wild varicella. It is intended to reduce the chance of chickenpox and may also reduce later complications associated with infection. Vaccination decisions depend on age, previous doses or infection, pregnancy status, immune health, and medicines that affect immunity. The [Chickenpox Vaccination](/treatments/preventive-care-and-vaccination/chickenpox-vaccination/) page gives related information.

Tell the vaccinator about pregnancy, immune-system conditions, severe allergies, recent vaccines, and medicines such as immune-suppressing treatment. Follow the local schedule advised by a qualified clinician. Mild soreness, redness, a low fever, or a small rash can occur; monitor how you feel and keep the injection area clean. Do not assume a new rash is harmless if it is extensive or you feel very unwell. A [GP Consultation](/treatments/consultations-and-assessment/gp-consultation/) can help review personal suitability.

Contact a clinician promptly for breathing difficulty, facial swelling, fainting, widespread hives, persistent high fever, confusion, or a rapidly spreading blistering rash after vaccination. Seek advice before vaccination if you may be pregnant, have weakened immunity, or take treatment that suppresses immune responses. A clinician can distinguish a vaccine reaction from [Chickenpox](/conditions/chickenpox/) or another illness.

Ask whether this vaccine is suitable for you, which schedule applies, and what to do if a dose was delayed. Discuss pregnancy planning, immune conditions, current medicines, recent exposure to chickenpox, and whether a fever or rash needs review.