Mumps in vaccinated adults: what to know

The MMR vaccine trains the immune system to recognise the mumps virus. Protection is strong but not absolute, so exposure can occasionally be followed by infection. A vaccinated person may have milder cheek or jaw swelling, fever, headache, tiredness, muscle aches or reduced appetite. Swollen glands can occur on one or both sides. Symptoms overlap with other infections, so swelling alone cannot confirm mumps.

A clinician may consider your vaccination history, an exposure, examination findings and testing. Until assessed, avoid close contact, sharing cups or utensils, and crowded settings. Phone ahead before attending a clinic.

Contact a GP for advice if mumps is possible, especially after contact with someone who has it. Rest, drink regularly and choose soft foods if chewing hurts. Use only symptom medicines suitable for you and follow the label or a clinician's directions. Do not take antibiotics unless prescribed; they do not treat a viral infection.

Ask how long you should stay away from work, school or vulnerable household members. Review your vaccine record with the clinician rather than arranging an extra dose while unwell. More background is available in [Mumps](/conditions/mumps/) and [MMR Vaccination](/treatments/preventive-care-and-vaccination/mmr-vaccination/).

Seek urgent medical help for severe headache, neck stiffness, confusion, fainting, trouble breathing, inability to keep fluids down, or rapidly worsening illness. Contact a clinician promptly for marked testicular or pelvic pain, hearing changes, or persistent vomiting. A fever or swollen glands can be part of mumps, but their presence does not establish the diagnosis; see [Fever](/symptoms/fever/) or [Swollen Glands](/symptoms/swollen-glands/) for related guidance.

Could my symptoms be mumps or another infection? Do I need a swab or another test? How should I protect people at home, and when can I return to normal activities? Does my vaccine record need review?