Mumps after the MMR vaccine: what to know

The MMR vaccine can be followed by temporary soreness, fever or feeling unwell. Swelling near the cheeks or jaw, especially with tenderness, may also prompt concern about mumps, but symptoms alone cannot confirm the cause. Mumps is an infection affecting salivary glands and can spread to other people. A vaccine-related reaction and an infection can look similar at first, so note when symptoms began and whether they are changing.

Check for fever and swollen glands, and mention any recent contact with someone who has mumps. Do not assume that facial swelling after vaccination proves infection, and do not dismiss it without advice if it is marked or worsening.

Rest, drink fluids and use simple foods if chewing is uncomfortable. Follow the label or a clinician's advice for any fever or pain medicine that is suitable for you. Avoid close contact, sharing cups and preparing food for others until a clinician advises whether mumps is possible. Call a GP practice before attending so staff can reduce exposure to other patients. A GP consultation can review the timing, examination findings and vaccination history.

Arrange prompt medical advice for new swelling around the jaw, persistent fever, severe headache, vomiting, marked drowsiness, testicular pain or abdominal pain. Seek urgent help for trouble breathing, confusion, a seizure, inability to swallow fluids or signs of dehydration. Pregnancy, a weakened immune system or close contact with a confirmed case are additional reasons to contact a clinician early.

Ask whether the timing and pattern fit a vaccine reaction or possible mumps, whether testing is needed, how long to avoid close contact, and which medicines are appropriate for your age, pregnancy status or health conditions.