Introduction

MMR is the combined vaccine that protects against the following diseases:

• measles
• mumps
• rubella

The vaccine was introduced in 1988. Since then, the number of children who catch these diseases has fallen to an all-time low.

The first MMR vaccination is given to children at around 13 months of age. A booster dose is given before they start school (usually between three and five years of age).

The vaccine contains weakened versions of live

Measles, mumps and rubella viruses (see box, left). Because the viruses are weakened, people who have recently had the vaccine cannot infect other people. Measles, mumps and rubella have serious complications, which is why it is important that your child is vaccinated against them (see Why it should be taken, above).

Currently, there are no licensed single vaccines for either measles or mumps.

Why the MMR Vaccine Should be Given

Measles, mumps and rubella are diseases that have serious complications:

• Measles causes a range of symptoms, which can include ear infection, bronchitis, convulsions (fits) and brain damage. Measles can be fatal.
• Mumps used to be the main cause of viral meningitis in children. It also causes temporary deafness, miscarriage, inflammation of the pancreas and pain and swelling in the testicles in men.
• Rubella can lead to painful joints, blood disorders and swelling of the brain (encephalitis). It damages unborn babies and may cause miscarriage if women catch the disease while pregnant. Babies born with congenital rubella syndrome may have some degree of deafness, blindness and damage to their heart or brain.

There has been some controversy about the MMR vaccine in recent years, following a study published in The Lancet in 1998 by Dr Andrew Wakefield. His initial study appeared to show a link between the MMR vaccine and autism and bowel disease. However, his research was not carried out correctly and has since been discredited.

Subsequent studies have been unable to find a link between MMR and autism or bowel disease.

When the MMR Vaccine Should be Given

Children
The first MMR vaccination is given to children at around 13 months of age, when the immunity the baby got from its mother fades.

Children are given a booster dose before they start school (usually between three and five years of age). Between 5 and 10% of children are not fully immune after the first dose. The booster gives increased protection, and less than 1% of children remain at risk after it.

Women considering pregnancy
Women who are considering becoming pregnant should ask their doctor to screen them (using a simple blood test) to check whether they are fully immune to rubella. Women who were born before 1988 were only given one vaccination against rubella, compared with those born later who received the recommended two doses of MMR.

Women whose protection from rubella is low or uncertain are routinely offered a single rubella vaccination. However, if this is not available, they may be offered MMR to provide the immunity they need.

Rubella in pregnancy can cause serious problems in the developing baby. Doctors advise women to avoid becoming pregnant for one month after a rubella vaccination. Pregnant women who were not screened before conceiving and who find out (through routine antenatal blood tests) that their immunity is low will be offered a rubella vaccination after delivery of the baby, normally at their six-week postnatal check.

Protecting people in a measles outbreak
In the event of a measles outbreak, MMR can protect people who have come into contact with the disease in the previous three days. This is because measles antibodies develop more quickly following vaccination than they do following natural infection.

Current advice states that there are no negative effects from vaccinating people who are already immune (for example, if there is any doubt whether they have already been vaccinated).

Side Effects of the MMR Vaccine

MMR contains three separate vaccines in one injection. Each vaccine can have different side effects that happen at different times:

• About one week to 10 days after the MMR injection, some children get a very mild form of measles. This includes a rash, high temperature, loss of appetite and general feeling of being unwell for about two or three days.
• About three to four weeks after the MMR injection, one in 50 children develops a mild form of mumps. This includes swelling of the glands in the cheek, neck or under the jaw. It lasts for a day or two.
• One to three weeks after receiving the rubella vaccine, some adult women experience painful, stiff or swollen joints, which lasts around three days.

Rare side effects
In rare cases, a child may get a small rash of bruise-like spots about two weeks after the injection. This side effect, linked to the rubella vaccine, is known as idiopathic thrombocytopenic purpura (ITP).

It has been estimated that ITP develops in less than one in every 22,000 doses of the MMR vaccine and that there is a greater risk of developing the condition from the diseases that the vaccine prevents.

ITP usually gets better on its own, but, as with any rash, seek advice from your doctor as soon as possible. In very rare cases, children can have severe allergic reactions straight after an immunisation. This happens in about one in 100,000 immunisations for MMR. If the child is treated quickly, they will recover fully.

Medical staff who give immunisations are trained to deal with allergic reactions to vaccines.

People who have been recently immunised cannot infect others with the viruses contained in the MMR vaccine.

Frequently Asked Questions

Can my child have the Hib/MenC jab together with the MMR and pneumococcal jabs?
Yes, these vaccines can be given together.

The recommended childhood vaccination schedule indicates that MMR is given at around 13 months of age at the same time as Hib/MenC and the pneumococcal conjugate vaccine (PCV).

My child is allergic to eggs. Can she have the MMR vaccination?
Yes, the MMR vaccine can be safely given to children who have a severe allergy to egg. This is because MMR vaccine is grown on chick cells, not the egg white or yolk. If you have any concerns, talk to your health visitor, nurse or doctor.

I don't know if my teenage daughter has had her second MMR jab. What should I do?
It is important that she has the MMR jab now. If you are not sure whether she has ever had the MMR jab, she should have one dose now and make an appointment to have a second dose in three months' time. An extra MMR dose will not cause any harm.

Does the MMR jab contain thiomersal (mercury)?
No, the MMR vaccine has never contained thiomersal (a preservative containing mercury that is used in some vaccines).

My child is due for his MMR jab but I am concerned about the connection between autism and MMR. Could it put him at risk?
There is currrently no scientific evidence available to support the suggestion of a link between MMR and autism, so you should not worry. Your child should have his MMR jab to protect him against measles, mumps and rubella.

Our son was born six weeks prematurely. Should we delay getting him vaccinated?
No. Babies should receive their vaccinations according to the recommended schedule, irrespective of when they are born.

A month after I got vaccinated for MMR, I found out I was pregnant. Will my baby be ok?
Evidence from clinical trials suggests that there will be no harm to your baby. However, you should discuss this with your doctor at the earliest possible opportunity to be further reassured.

Can my child have the MMR vaccine if they have already had single vaccines?
Unless there is reliable evidence that your child has been fully vaccinated against measles, mumps and rubella, they will still need to have the MMR vaccine, even if they have had a single vaccine as well.

Live vaccines, such as the MMR vaccine, should be given at least four weeks apart. If your child has received a live single vaccine, they will have to wait at least four weeks until they can have the MMR vaccine.

My son is 18 and has been asked to have a second MMR jab before university. Is this sensible?
Many universities are recommending their students have MMR, because there have been outbreaks of mumps.

To ensure he is fully protected against mumps, he needs to have had two doses of MMR. Even if he has already had two doses of a measles vaccine, having a third to make sure he is protected against mumps will not cause any harm.

If my child develops a mild case of measles after receiving their first MMR vaccine, are they contagious to non-vaccinated children?
No. Post-vaccination symptoms are not infectious, so your child will not pass anything on to non-vaccinated children.

My baby had measles at the age of six weeks. Can I get the vaccine without the measles component?
Although your baby had measles at six weeks, it is still advised that they have the MMR. This will help protect your baby against mumps and rubella and will also boost the antibodies your baby has already developed against measles.

We are due to go travelling and my 14-month-old son is due to have his MMR jab three weeks before we go. Will he have developed immunity before we go?
And can he have travel vaccines at the same time as the MMR? Immunity to measles, mumps and rubella starts to develop after two weeks, so having his MMR three weeks before travelling is fine. It is also fine to have other travel vaccines on the same day as the MMR.

My child is receiving their MMR jab tomorrow. How long should I leave it before taking them swimming?
There is no reason why your child cannot resume normal activities, including swimming, straight after receiving their MMR jab.

Does MMR give a lifetime of immunity?
The immunity that MMR gives is probably lifelong. It is known that individuals will remain immune for at least 30 years against measles, 23 years against rubella and 19 years against mumps - in other words, for the amount of time that the vaccines have been available.

If in the future evidence shows that immunity is fading, decisions would be made about offering a further dose in, for example, the adult years.

I have heard that mumps is going around. I thought that MMR prevented mumps, so why is this happening?
You need two doses of MMR to be protected against mumps. MMR was introduced in 1988, with a second dose introduced in 1996, so some teenagers and young people have not had two doses of MMR.

This has led to several recent outbreaks of mumps among this age group. If you think this applies to you, you should book an appointment for the second dose now. If you have never had the MMR vaccine, you should have one dose now and another three months later.

Our 14-month-old son had his MMR jab last week. I am 12 weeks pregnant - is there any risk of my son affecting my unborn child?
There is no risk to your unborn baby as it is impossible for anyone to catch any of the diseases from a child recently vaccinated with MMR.