Safety of MMR vaccination
The risk of MMR causing serious harm is extremely small. MMR is considerably safer than getting measles (or mumps and rubella). See the following comparison.
Effects of the disease
1 to 3 out of 1,000 people with measles will die in developed countries.
1 in 10 people with measles will get complications including:
- diarrhoea
- ear infections
- pneumonia
- other diseases of the airways (like bronchiolitis and croup)
- ulcers of the eye (corneal ulcers)
- idiopathic thrombocytopenic purpura (low platelets)
Measles in pregnancy increases risk for premature labour, miscarriage and stillbirth.
1 in 1000 people with measles develop inflammation of the brain (encephalitis) - 15 in 100 of these people die and approximately 30 in 100 are left with permanent brain damage.
1 in 100,000 people who have had measles will, years later, develop a serious brain inflammation called subacute sclerosing panencephalitis (SSPE). This serious complication always results in death.
Possible side effects of MMR
After MMR vaccination, a fever of 39.4°C or more happens in 5% to 15% of tamariki (children). This usually develops 6 to 12 days after vaccination and lasts 1 to 2 days. 5% of tamariki get a rash at the same time.
Side effects of the different components of the MMR vaccine can also include:
- mild swelling of the glands around the jaw 10 to 14 days after vaccination
- generalised swollen glands 2 to 4 weeks after vaccination
- joint pain 2 to 4 weeks after vaccination - this is more common in adult women than tamariki
Rare side effects of MMR
- temporary low platelet count (idiopathic thrombocytopenia purpura)
- anaphylaxis
- febrile seizures
References
Immunisation Advisory Centre. University of Auckland. http://www.immune.org.nz/diseases/measles
Immunisation Handbook 2020 (measles chapter). Wellington: Ministry of Health.