Mumps
Mumps virus
Last updated 26 March 2025
Overview
Mumps is an acute viral disease characterised by fever, swelling and tenderness of one or more salivary glands.
Disease epidemiology
Mumps occurs worldwide and usually affects children and young adults. In countries that have included mumps vaccination in their immunisation programmes, the incidence of mumps has declined significantly. Humans are the only known reservoirs of the infection.
In Singapore, mumps vaccination has been included as part of the National Childhood Immunisation Programme since January 1990, when the monovalent measles vaccine was replaced by the trivalent measles, mumps, rubella (MMR) vaccine.
In 1999 and 2000, there was a significant increase in the number of cases due to the low protective efficacy of vaccines containing the Rubini strain, which had been used from 1993 to 1995. Following the resurgence in cases, a more efficacious vaccine replaced the Rubini strain-containing vaccine. Since then, the incidence of mumps has declined rapidly and remained low since 2010.
Pathogen(s)
Mumps virus.
Transmission
Mumps primarily transmits through inhalation or direct deposition of infectious respiratory particles (IRPs) such as when an infected person coughs or sneezes. It can also spread via contact with contaminated surfaces such as when IRPs settle on surfaces or transfer through contact (e.g. handshake) before reaching the mouth, nose or eyes.
Incubation period: Typically 16 to 18 days; ranging from 12 to 25 days.
Infectious period: 1 week before and up to 9 days after the onset of parotitis.
Clinical features
About 30% of cases may present with a mild respiratory tract infection with no apparent salivary gland swelling or a subclinical infection.
Typically, mumps begins with a prodrome of malaise, headache, fever, and anorexia lasting 2 to 3 days. This is followed by pain and swelling in 1 or both parotid glands (or other salivary glands), increasing for 2 to 3 days, then resolving over 1 week.
Epididymoorchitis, usually unilateral, is the most common complication occurring in approximately 15% to 30% post pubertal males, typically 5 to 10 days after onset of parotitis. Other complications include oophoritis, meningoencephalitis, and sensorineural hearing loss.
Differentials for parotid gland swelling include bacterial parotitis, other viral parotitis (parainfluenza, influenza, coxsackievirus), viral lymphadenitis, parotid calculus, or tumour. Bilateral parotid swelling can be seen in children with HIV infection.
Risk factors
All persons who are unvaccinated or partially vaccinated.
Diagnosis
Positive results for Polymerase Chain Reaction (PCR), virus isolation or serology (IgM or four-fold rise in antibody titre).
Treatment and management
There is no specific antiviral therapy. Treatment is symptomatic.
Precaution, prevention, and control
Isolation measures
All cases should be isolated and managed under airborne precautions.
Contact management
Susceptible contacts should receive MMR vaccination.
Vaccination
Vaccination is the main preventive measure against mumps.
The National Childhood Immunisation Schedule recommends that all children should receive two doses from age 12 months onwards, at least 4 weeks apart.
The National Adult Immunisation Schedule recommends that adults (18 years or older) who have not been vaccinated, or lack evidence of past infection or immunity should receive 2 doses (the first dose, and the second dose 4 weeks after the first dose).
Notification
Mumps is a legally notifiable disease in Singapore.
Who should notify:
Medical practitioners
Laboratories
When to notify:
Medical practitioners – on clinical suspicion
Laboratories – upon laboratory confirmation
How to notify:
Please refer to the Infectious Disease Notification for more information.
Notification timeline:
As soon as possible. No later than 72 hours.
Resources
Please refer to the Weekly Infectious Diseases Bulletin for the number of mumps cases in Singapore.
For more information on mumps, please refer to the World Health Organization website.
For general travel advisory, please refer to Health Advice for Travellers.