MMR Immunisation

Authored by , Reviewed by Dr Jacqueline Payne | Last edited | Meets Patient’s editorial guidelines

A dose of MMR vaccine is usually given to children aged 12-13 months. A second dose is usually given as a preschool booster. The MMR vaccine is safe and protects against illnesses which have the potential to lead to complications which can be very serious.

MMR stands for measles, mumps and rubella. These are three different diseases which are caused by three different viruses. The vaccines given to immunise against measles, mumps and rubella (MMR) are all combined into one injection - the MMR vaccine.

Even if you think your child has already had one of these diseases, your child should still have MMR immunisation.

  • The first dose of vaccine is usually given between 12 and 13 months. It is usually given at the same time as the Hib/MenC vaccine - this stands for 'Haemophilus influenzae type b/meningitis C' and the pneumoccocal vaccine (given as separate injections).
  • A second dose is usually given at age 3 years and 4 months to 5 years at the same time as the DTaP/IPV injection. (DTaP stands for diphtheria (D), tetanus (T) and acellular pertussis (aP) (whooping cough). IPV stands for inactivated polio vaccine. Polio is short for poliomyelitis.)

Even if a dose of MMR is delayed for any reason, it can still be given at a later age. If necessary, MMR vaccine can be given at any age.

Most children are perfectly well after having a dose of measles, mumps and rubella (MMR) vaccine. Serious problems with the MMR vaccine are extremely rare. However:

  • Some children develop a mild raised temperature (fever) and a faint rash 7-10 days later. This should only last for 2-3 days and is of no concern.
  • Mild reactions such as a slight fever, a mild sore throat and joint pains sometimes occur about 1-3 weeks after the injection. These soon subside and are of no consequence.
  • A few children develop a mild swollen face (like a mild form of mumps) about three weeks later. Any swelling will gradually go down.

None of these reactions is infectious or serious. If necessary, you can give paracetamol or ibuprofen to ease pain and fever. Any reaction to the vaccine is much less after the second vaccine is given.

  • Pregnant women. Also, you should not become pregnant for one month after having a rubella (MMR) immunisation. It is safe, however, to have if you are breast-feeding.
  • If you are having chemotherapy or if your immune system is suppressed for other reasons.
  • If you are seriously ill (for example, if you have a severe infection) you should postpone the vaccine until you are better. However, if the illness is minor, the vaccine need not be delayed. The typical example is a child who gets a tummy bug or earache on the day the vaccine is due. Providing they do not have a temperature and are well in themselves, the injection can be given.
  • If you are allergic to the medicines neomycin or gelatin (which are part of the vaccine). There is a version of the vaccine available which does not contain gelatin if you are allergic to, or prefer not to have, gelatin.

Note: if you are allergic to eggs, you may receive the vaccine safely.

In the past, there has been speculation that the MMR vaccine may somehow cause autism or inflammatory bowel disease. This was a scare following a published study which has since been discredited and removed. Large studies have all concluded that there is no evidence to link MMR immunisation to either of these conditions. Unfortunately, following the scare, fewer children had the MMR vaccine, and as a result in 2006-2007, the UK had the third highest rate of measles in Europe.


Measles is a highly infectious illness caused by the measles virus. Beginning like a bad cold, the child then develops a raised temperature (fever) and a rash. The child feels miserable and may be unwell for a week or so with a bad cough and a high temperature.

Measles is much more serious than many people think. In fact, of all childhood infections, it is the one most likely to cause the complication of inflammation of the brain (encephalitis), sometimes resulting in brain damage. It can also cause convulsions, ear infections, bronchitis and pneumonia, which can lead to long-term lung problems. Each year a number of children die from measles. In developing countries it is a major cause of childhood death. After the MMR vaccine was introduced to the UK, cases of measles and deaths from measles were drastically reduced. Unfortunately, there have been outbreaks of measles again in children in some areas of the UK over the past 10 years. This is due to some children not receiving the MMR vaccine.


Mumps infection typically causes inflammation and swelling of the glands around the face, neck and jaw. It is usually a mild illness but complications occur in some children, such as inflammation of the pancreas (pancreatitis), inflammation of the testicles (orchitis), meningitis and inflammation of the brain (encephalitis). Mumps may cause permanent deafness in one ear. Mumps is equally dangerous for boys and girls.

Rubella (German measles)

Rubella is usually a mild illness causing a rash, sore throat and swollen glands. However, if a pregnant woman has rubella, the virus is likely to cause serious damage to the unborn child. Rubella can lead to damage to the heart, brain, hearing and sight. The baby is likely to be born with a very serious condition called the congenital rubella syndrome. See separate leaflet called Rubella (German Measles) and Pregnancy.

Since rubella immunisation was introduced in 1970 there has been a dramatic fall in the number of babies born with the congenital rubella syndrome. Rubella is now a very uncommon infection in the UK as a result of the vaccination programme.

Further reading and references