Mumps

Condition

Acute infection caused by paramyxovirus, transmitted via respiratory secretions/saliva; rare in Australia due to immunisation. Unvaccinated: typically age 5–9; vaccinated populations: adolescents/young adults. ~1/3 of infections are asymptomatic; parotitis (usually bilateral) occurs in ~2/3 of clinical cases. A rash is rare/not well described.

Clinical features

Fever, headache, malaise, myalgia, anorexia, followed by painful parotid gland swelling that can obscure the angle of the jaw.

Investigations

Viral buccal swab for PCR; mumps serology can be difficult to interpret in vaccinated individuals — contact a microbiologist if needed.

Management

Symptomatic treatment; isolate for 5–9 days from onset of glandular swelling (advice varies by source). Historically thought to raise spontaneous abortion risk if contracted in the first trimester, but more recent research has found no increased rate of spontaneous abortion or premature birth with mumps infection in pregnancy. Common complications: orchitis (15–30% of post-pubertal males, usually unilateral, subsequent sterility rare), meningeal symptoms/aseptic meningitis, abdominal pain. Rare: oophoritis, encephalitis, arthritis, deafness, pancreatitis.