The MMR vaccine protects you against 3 viral infections – measles, mumps and rubella. The vaccine is a live vaccine, which is made using live mumps, measles and rubella viruses that have been weakened (or attenuated).

After vaccination, the weakened vaccine then teaches your immune system to recognise the virus, so it knows how to attack if it ever comes across it. Read more about live vaccines.

Vaccination with the MMR vaccine is the best way to protect against measles, mumps and rubella. While these infections may be mild in some people, they can cause serious complications in others

• Measles: The infection can be serious, with 1 in 10 needing to go to hospital. Complications include diarrhoea/hamuti (which can lead to dehydration), ear infections (which can cause hearing loss), pneumonia (which is the most common cause of death) and encephalitis (brain inflammation), which can cause brain damage. Read more about measles.
• Mumps: The symptoms of mumps are usually mild, such as swollen salivary glands (at the side of your face), headache and fever, but it can cause serious complications such as deafness, swollen testicles or ovaries, and meningitis. Read more about mumps.
• Rubella (also called German measles): This is usually a mild infection that gets better within about 7–10 days, but it becomes a serious concern if a pregnant woman catches the infection during the first 20 weeks of pregnancy. This is because the rubella virus can affect the development of the baby and cause severe health problems such as eye problems, deafness, heart abnormalities and brain damage. Read more about rubella. 

The MMR vaccine is given as an intramuscular injection (injected into a muscle in your thigh or upper arm). It is given as 2 doses at least 4 weeks apart.

After a single dose of MMR vaccine, 90–95 out of 100 people will be protected from measles, 69–81 protected from mumps and 90–97 from rubella. After a second dose of MMR vaccine the number of people protected from these diseases increases, and almost everyone will be protected from measles and rubella, and up to 88% (88 out of 100 people) protected from mumps.

It's really important to have both doses of the vaccine so you are well protected.

• Anyone born on/after 1 January 1969 who has not had two doses of the MMR vaccine should have the MMR vaccine.
• Adults born before 1969 are considered to be immune to measles as measles was very infectious before 1969, and there was no vaccine available in Aotearoa New Zealand until then, so most adults were highly likely to be exposed. The MMR vaccine may still be needed for protection from mumps and rubella – check with your doctor if you are not sure.
• The MMR vaccine is part of the childhood immunisation schedule for children at 12 months and 15 months of age.

Women planning a pregnancy

All women of childbearing age need to know if they are protected from rubella. In pregnant women, rubella can cause serious complications to the unborn baby, especially during the first 20 weeks of pregnancy. Immunity from the mother can stop the baby becoming infected.

If you are planning a pregnancy, check with your midwife or doctor whether you need to be vaccinated against rubella. When you get vaccinated, avoid getting pregnant for at least 1 month afterwards. 

Measles outbreak

A single dose of MMR vaccine given to an unvaccinated person within 72 hours of first contact with an infectious person may reduce the risk of developing disease.

For babies, an additional dose of measles vaccine can be given from 6 months of age. Babies immunised before they are 12 months old will still need 2 doses according to the schedule (at 12 months and 15 months).

Travel

While measles cases in Aotearoa New Zealand are usually rare, the disease is regularly brought into the country through international travel and there was an outbreak in 2019. If you are travelling overseas, make sure you are fully vaccinated against measles before you go.

If you’re unsure of your vaccination status you can check your Well Child Tamariki Ora or Plunket book, or contact your general practice. If you are not sure whether you have had 2 doses of MMR, it is recommended that you get a vaccine. There are no safety concerns with having extra doses.

If you or your child has had measles, 2 doses of MMR are recommended for mumps and rubella protection. There are no safety concerns with having the vaccine for people who are already protected from measles.

The MMR vaccine is a live vaccine, it should not be given if you:

• are pregnant
• have a severe weakness of your immune system
• have had a severe allergic response (anaphylaxis) to this vaccine or part of this vaccine before
• have had another live vaccine within the past 4 weeks.

Like all medicines, vaccines can cause side effects, although not everyone gets them. Most side effects are mild and short lived. The chance of a severe reaction from MMR is very small, but the risks from not being vaccinated are very serious.

Because the MMR vaccine combines 3 separate vaccines (measles, mumps, rubella) in a single injection, each vaccine can cause reactions at different times after the injection. There's less chance of side effects after the second dose of MMR than the first.