Measles, mumps and rubella (MMR) vaccine

The measles, mumps, and rubella (MMR) vaccine is a single, combined vaccine that protects against three diseases – measles, mumps, and rubella. In the UK, the MMR vaccine is offered as part of the NHS childhood immunisation programme. If you didn’t have the MMR vaccine when you were a baby, you can have it when you’re older.

About the MMR vaccine

The measles, mumps, rubella (MMR) vaccine is the safest and most effective way to protect against measles, mumps and rubella. Before the MMR vaccine was introduced in 1988, there were single vaccines for measles and rubella, but all three diseases were still common. It’s now rare for children to develop them, although outbreaks do happen when the number of people having the vaccine drops.

If you haven’t had the vaccine, you’re at much greater risk of developing measles, mumps, and rubella. Having the vaccine also helps to protect those who are unable to have it (see our section on people who shouldn’t have the vaccine).

Measles, mumps, and rubella are caused by viruses that are spread by coughs and sneezes. There’s no cure for these diseases – doctors can only treat the symptoms while you recover from the illness. Although most people recover without any long-term effects, each illness can have serious consequences, and may even be fatal.

Measles

Measles can cause a fever, cold-like symptoms, sore red eyes, and a rash. This usually starts on your face, then spreads down your body and reaches your hands and feet within a few days. Most people feel better about a week after the rash develops. But for up to one in five people, measles can go on to cause potentially serious complications. These include:

• diarrhoea
• ear infections
• pneumonia
• less commonly, seizures (fits), and inflammation of the brain

If you catch measles as an adult, it’s likely to be more severe and you’re at greater risk of complications.

Measles is highly contagious. It infects nearly all people who aren’t immune and come into contact with it. If you suspect or know you have measles, stay at home and don’t have any contact with vulnerable people. People who are vulnerable include those who are pregnant and those with a weakened immune system. If you have measles, you should stay away from school, nursery, or work for at least four days after the rash started.

Mumps

Not everyone who gets mumps gets symptoms, but many people develop a fever and feel generally unwell. It’s common to have swollen salivary glands (the glands on either side of your face, just below your ears). Common complications include swollen testicles or ovaries, which may affect fertility. The infection can also cause viral meningitis, inflammation of the brain, and hearing loss.

Mumps is a contagious infection. Before the MMR vaccine was introduced, most people would get mumps if they came into contact with it. If you get mumps, stay away from school, nursery, or work for at least five days after your symptoms started.

Rubella (German measles)

Rubella is sometimes known as German measles. It’s usually a mild infection, and some people don’t get any symptoms. Or you may just get cold-like symptoms and a rash for a few days. But it can be very dangerous if you catch it in early pregnancy because it can cause miscarriage, and serious disabilities in babies. These include blindness, deafness and learning difficulties.

Before the introduction of the MMR vaccine, around 200 to 300 babies a year were born with complications due to rubella.

If you get rubella, stay away from school, nursery, or work for at least five days after the rash first appeared.

Having the MMR vaccine

Young children have the measles, mumps, and rubella (MMR) vaccine as a single injection into their thigh. Older children and adults have it in their upper arm. The MMR vaccine for adults is the same as that for children.

Children

Children should be offered the MMR vaccine through their GP surgery as part of the routine immunisation schedule. Your child will need two doses of MMR to get full protection. Children are invited to have the first dose on or soon after their first birthday. They’ll then have a second pre-school dose when they’re three years and four months old (or soon after).

If you have an older child who hasn’t had the full MMR vaccine, contact your GP surgery to get it. Older children may also be offered missing doses of MMR through school, alongside other booster doses. For an older child, there should be a gap of at least a month between doses.

The MMR vaccine may also be given to control any outbreaks of measles. Children over six months who have been in contact with a person infected with measles can have the MMR vaccine within three days of being exposed to the infection. Unfortunately, the MMR vaccine can’t be used in the same way after exposure to mumps or rubella. This is because the body’s response to the mumps and rubella components of the vaccine is too slow to offer immediate protection.

Adults

You can choose to have the MMR vaccine as an adult. You may already be immune to measles, mumps, and rubella if you had the diseases as a child. If you were born before 1970, you may have had single vaccines for measles and rubella. If you’re unsure whether or not you’ve had any of the vaccines or any of the diseases, speak to your GP. You can have an MMR vaccination even if you had the single vaccines before. In that case, your immune system will recognise and quickly destroy the relevant active components in the MMR vaccine. If you have the MMR vaccine as an adult, you’ll have a gap of at least a month between doses.

Pregnancy

If you’re planning for a baby, it’s important to get vaccinated before you get pregnant. This is particularly to protect yourself against rubella because rubella is a dangerous infection in pregnancy.

If you’re already pregnant and don’t have any record of being vaccinated, you can get it soon after your baby is born. It’s not recommended that you have the MMR vaccine when you’re pregnant.

For more information, see our information on rubella in the section about the MMR vaccine.

How the MMR vaccine works

The MMR vaccine is a live vaccine that’s made from weakened forms of each of the measles, mumps, and rubella viruses. They’re not strong enough to cause these three infections, but they will stimulate your immune system and trigger immunity. This means that if you come into contact with any of the three viruses in the future, your immune system will recognise it and protect you from getting the disease.

You need two doses of the MMR vaccine to get full protection from measles, mumps, and rubella. Most people, but not everybody, develop immunity after the first dose. After the second dose, more than 99 out of 100 people will be completely protected against measles and rubella. Protection against mumps is slightly lower, but mumps is much less severe if you’ve had the vaccine.

If you’ve received two doses of the MMR vaccine, you should be protected for life. You won’t need another MMR vaccine booster dose.

People who shouldn’t have the MMR vaccine

Some people shouldn’t have the MMR vaccine or should check with a doctor first. Check if any of the following applies to you.

• You’re pregnant – be cautious: it’s advised that you don’t have the vaccine when pregnant. But data suggests there aren’t safety concerns. So don’t worry if you find out you’re pregnant after having it.
• You have a severely weakened immune system – for instance, if you take immunosuppressant medicines.
• You’ve had a severe allergic reaction to gelatine (a substance used in some vaccines). Ask your GP if you’d prefer the gelatine-free version of the MMR vaccine.
• You’ve had a severe allergic reaction to an antibiotic called neomycin. Neomycin is an ingredient in the MMR vaccine. It stops bacteria from growing and contaminating the vaccine.
• You’ve had a severe allergic reaction to an MMR vaccine before. In this case, you’ll need to be assessed by an allergy doctor first.

The MMR vaccine is grown in the laboratory on chick cells but there isn’t enough egg protein in the vaccine to cause an allergic reaction. Studies show the vaccine is safe for children with an egg allergy.

You can still have the MMR vaccination if you have a minor illness. But you might want to delay it if you’re very ill with a fever. Call your GP surgery to check if you’re unsure.

Side-effects of the MMR vaccine

The measles, mumps, rubella (MMR) vaccine contains weakened live viruses. You or your child may have some mild side-effects of the viruses after the vaccination. This is to be expected and is a sign that the vaccination has worked. The three viruses in the vaccine act at different times and may produce different side-effects as they start to work.

Side-effects include the following.

• Fever and/or rash and generally feeling unwell. If you get this side-effect, it will usually be about one to three weeks after the vaccination and will last for around 2 to 3 days. You can take paracetamol or ibuprofen to reduce any symptoms of fever.
• Swollen glands. Swollen glands usually appear around three weeks after you had the MMR vaccine. This should only last for a short time.
• Febrile convulsions. These are seizures or fits linked to fevers in children. A febrile convulsion is rare but if it does happen, it’s usually within 6 to 11 days of having the MMR vaccine. These convulsions can be scary and upsetting to see but they don’t cause any long-term harm. Infection with the measles virus is far more likely to cause febrile convulsions than having the MMR vaccine.
• Bruise-like rash. There’s a very small risk of developing a condition called immune thrombocytopenia (ITP). It usually happens within six weeks of having the MMR vaccination. ITP causes a rash that looks like tiny bruises and will get better on its own. This rash is more common with measles or rubella than with the vaccine.

MMR vaccine side-effects are usually mild. Most importantly, they aren’t as serious as the potential consequences of having measles, mumps or rubella. You’re less likely to get side-effects after the second dose of the vaccine. If you’re concerned about any symptoms after MMR vaccine, contact your GP surgery.

MMR and autism

There’s overwhelming evidence that the MMR vaccine does not cause autism. Research published in the past wrongly suggested there may be a link between the two. This led to fewer parents getting their children vaccinated with MMR. As a result, there was an increase in the number of people who got measles and mumps in the following years. There has since been lots of research into if there could be a link between MMR and autism; no connection has been found.

Single vaccines

The MMR vaccine is given as a combined vaccine, rather than a series of single ones. No country in the world recommends giving vaccines against the three infections separately. This is due to the following reasons.

• You or your child would need to have six injections in total. This is more unpleasant because each injection can be uncomfortable and possibly distressing for children.
• There may be a longer delay before being completely vaccinated. This would leave you or your child at risk of measles, mumps, or rubella for longer.
• It could result in fewer children having all the necessary vaccinations. This would increase the level of measles, mumps, and rubella in the UK.
• Single vaccines haven’t been researched very well. For example, there isn’t any guidance about how they should be given or how much of a gap is needed between injections. Also, there isn’t enough evidence to say how effective or safe they are.

All the evidence shows that the MMR vaccine is the safest and most effective way to protect you or your child against measles, mumps, and rubella. The only single vaccines available in the UK are unlicensed products that have been imported into the country. This means they haven’t been independently tested for how safe they are or how well they work. It’s important to be aware of this if you’re considering using these products.