Complications of mumps
Most children recover from mumps. Unimmunised teenagers and adults who get mumps are more likely to experience severe disease and complications. Complications in people with mumps include:
- pain and swelling of a testicle (orchitis) in about 1 in 5 teenage or adult males - infertility is rare
- viral meningitis in up to 15 in 100 people - most make a full recovery
- pain and swelling of an ovary (oophoritis) in 1 in 20 teenage or adult females - infertility is rare
- temporary deafness
- serious and permanent deafness - this is rare, usually on one side
- brain inflammation (encephalitis) in about 1 in 6,000 people
- inflammation of other organs, such as pancreas, nerves, joints, breast, kidney, thyroid and heart
- death - this is rare
There is an increased risk of miscarriage in pregnant women who get mumps during the first 3 months of pregnancy. There is no evidence that mumps causes damage to unborn babies.
Possible side effects of MMR
After MMR immunisation, a fever of 39.4°C or more happens in 5 to 15 in 100 children. This usually develops 6 to 12 days after immunisation and lasts 1 to 2 days. 5 in 100 children 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 immunisation
- generalised swollen glands 2 to 4 weeks after immunisation
- joint pain 2 to 4 weeks after immunisation - this is more common in adult women than children
Rare side effects of MMR
- inflammation of the brain (encephalitis)
- idiopathic thrombocytopenia purpura (low platelets)
- aseptic meningitis
- anaphylaxis
- febrile seizures
References
Immunisation Handbook 2020 (mumps chapter). Wellington: Ministry of Health. [Accessed 04/07/2022]
