What are the side effects of the combined measles, mumps and rubella (MMR) vaccine?
Common side effects
- About 10 per cent of children who receive the MMR vaccine experience local swelling, redness or pain at the injection site. These symptoms usually resolve with one or two days.
- Between 5 and 15 per cent develop a high fever and tiredness or lack of energy (malaise) between 5 and 12 days after their first dose of the vaccine.
- About 5 per cent get a rash which cannot spread to anyone else.
- Side effects are more common after the first dose, recommended at 12 months.
Rare side effects
- Up to 1.6 per cent get swollen glands, a stiff neck or joint pains.
- About 0.03 per cent of children who get a first dose of MMR vaccine experience febrile convulsions (fits). These happen when a baby or child's temperature (fever) goes up suddenly.
Very rare side effects
- Between 0.003 and 0.005 per cent develop a blood disorder called thrombocytopaenia after their first dose of the MMR vaccine. Thrombocytopaenia causes children to bruise or bleed very easily. It usually lasts for between one and six months and then gets better.
- About 0.0001 per cent of people who get any of the vaccines have an allergic reaction that affects their whole body, called anaphylaxis. This reaction usually happens within 15 minutes of getting the vaccination and can be treated with an injection (epinephrine). People who have this reaction usually recover quickly and don’t experience any long-term effects.
What are the symptoms of mumps?
Usual symptoms
- Mumps usually starts with a high fever, headache, tiredness or lack of energy (malaise), muscle aches (myalgia), a sore throat, runny nose, cough and loss of appetite.
- About 60 to 70 per cent of people who have mumps develop swelling under one or both ears and jaws.
- About 30 per cent of people who catch mumps don’t get sick but they can spread it to other people and those people can get sick.
Common symptoms
- About 15 to 30 per cent of adolescent (teenage) boys and adult men with mumps get inflammation (swelling) of one or both of their testicles (balls). This only rarely causes infertility (being unable to make a woman pregnant).
Rare symptoms
- About 0.02 per cent of children with mumps develop a brain infection called encephalitis.
- About 1 per cent of children who get mumps encephalitis die.
- Mumps can cause miscarriage if a woman catches it early in her pregnancy.
REFERENCES / How vaccination has impacted the prevalence of mumps