Guidance

MMRV Vaccine Factsheet – Information for Parents and Caregivers

Published 22 December 2025

1. Overview of the MMRV vaccine 

• MMRV stands for Measles, Mumps, Rubella, and Varicella (chickenpox). 

• The MMRV vaccine is a combined vaccine that protects your child against four potentially serious diseases: 

  • Measles 

  • Mumps 

  • Rubella 

  • Varicella (chickenpox)

2. When children will be offered the MMRV vaccine

• From 1 January 2026, the measles, mumps, rubella and varicella (MMRV) vaccine will be introduced into the routine childhood immunisation schedule in the UK.  

• When children will be offered the MMRV vaccine will depend on their date of birth. 

• The MMRV vaccine will replace the measles, mumps and rubella vaccine (MMR) as part of the childhood routine 2-dose vaccination schedule. Please see guidance from the UKHSA on immunisation schedules and guidance for parents and carers.  

• For more information about eligibility, speak to your healthcare provider. 

3. Safety and effectiveness of the MMRV vaccine 

• The MMRV vaccine is one of the safest and most effective ways to protect your child from four potentially serious diseases: measles, mumps, rubella and varicella (chickenpox). 

• Like all vaccines approved for use in the UK, the combined MMRV vaccine has gone through a rigorous development process to test its safety, quality and effectiveness. 

• The MMRV vaccine has been used safely for many years in several countries including Canada, Germany, and Australia. 

• The MHRA regularly monitors and reviews suspected adverse drug reaction reports through the Yellow Card scheme to ensure all vaccines remain safe throughout their use. 

• Getting your child vaccinated with the MMRV vaccine is far safer than risking infection with measles, mumps, rubella, or varicella (chickenpox). 

4. Who can receive the MMRV vaccine 

• Most children can safely receive the MMRV vaccine. 

• Children with mild allergies including asthma, eczema, hay fever, or food intolerances, can safely receive the MMRV vaccine. 

• The MMRV vaccine is also safe for children with a severe egg allergy. This is because the vaccine does not contain any egg products. 

5. Who should not receive the MMRV vaccine 

• There are only a small number of reasons why a child cannot be immunised. 

• The MMRV vaccine contains weakened forms of the measles, mumps, rubella and varicella viruses, which stimulate a protective immune response. However, the vaccine should not be given to children who have a weakened immune system. If you think this applies to your child, speak to your practice nurse, doctor, or health visitor. 

• Children who have had a severe allergic reaction (anaphylaxis) to a previous dose of the MMRV vaccine or to any of the ingredients in it, should not receive the vaccine. If you are unsure, speak to your healthcare provider for advice. 

• If your child has had a severe allergic reaction to gelatine, they should have the gelatine-free MMRV vaccine. 

• If you have any concerns, speak to your practice nurse, doctor, or health visitor. 

6. MMRV vaccine side effects 

• Vaccination side effects are normally mild, potentially occurring at different times within a few weeks but lasting only for a few days. 

• The risk of serious side effects is very low, and the benefits of vaccination far outweigh any potential risks. 

• Some common side effects of the MMRV vaccine include: 

  • fever and rash, most commonly occurring a week or two after vaccination 

  • soreness at the injection site for a couple of days after vaccination 

• If your child develops a high temperature following vaccination:  

  • make sure they’re not wearing too many layers of clothes or blankets 

  • give them plenty to drink 

  • give them liquid paracetamol for children to bring their temperature down 

  • follow NHS guidance on vaccination tips for parents  

7. Less common side effects:  

• Around 1 in 1000 children may have a fit caused by a fever (also called a febrile convulsion) after having their first dose of MMRV. This is usually in the second week after the vaccine. For comparison, 1 in 43 children who catch measles will have febrile convulsions. If you think your child is having a fit, seek urgent medical advice. Febrile convulsions are common. One in 25 children will have a febrile convulsion before they turn 5. Usually children recover quickly and there are no long-term consequences.

• Very rarely, children may get a rash of small bruise-like spots in the 6 weeks after the vaccination. This is usually caused by the measles or rubella parts of the vaccine. If you see spots like these, take your child to the doctor to be checked. The doctor will tell you how to deal with the rash.  

• Very rarely, children may develop a chickenpox-like rash (fluid-filled spots) over their body, not at the site of injection. If your child has a rash like this, take them to the GP.  

• Fewer than one child in a million develops encephalitis (swelling of the brain) after the MMRV vaccine. However, if a child who has not been vaccinated catches measles, the chance of developing encephalitis is between 1 in 200 and 1 in 5,000.  

• If you think your child has signs of encephalitis (confusion, changes in behaviour, seizures, loss of consciousness, difficulty speaking, weakness or loss of movement in some parts of the body), call 999 or attend your nearest Accident and Emergency department. 

8. Report side effects to the Yellow Card scheme 

• You should report any suspected side effects of vaccination to the MHRA via a Yellow Card to: 

  • the Yellow Card website 

  • the Yellow Card app; download from the Apple App Store or Google Play Store 

• Reports help us gain a better understanding of vaccine interactions and safeguard patients through vigilant monitoring.