Mumps is an acute, generalised viral infection characterised by bilateral parotid swelling.
Before the introduction of the measles, mumps, and rubella (MMR) vaccine in 1987, it was common in children, but outbreaks are now more common amongst young adults, especially those who did not receive the MMR vaccine.
There were over 5000 cases of mumps in England in 2019, more than in any year since 2009.
Mumps is a viral infection caused by a paramyxovirus, usually affecting children or young adults.
The salivary glands are most commonly affected by Mumps, though it can infect organs such as testes, ovaries, pancreas, and brain.1
The Mumps virus is highly infectious and is spread by respiratory droplets and saliva.
The incubation period for Mumps virus is 16 to 18 days and transmission rates are highest one to two days prior to the onset of symptoms. Almost all those infected will develop life-long immunity.3
15-20% of those infected with the Mumps virus are asymptomatic.
Although, some may experience a prodrome of flu-like symptoms. These include fever, headache, malaise, myalgia, and anorexia.
Parotitis, or swelling of the parotid glands, then develops in 95% of symptomatic cases and usually lasts three to four days, though can last up to ten.
Mumps is also associated with orchitis and meningitis/encephalitis (see complications section).
Mumps parotitis is usually bilateral and can cause distortion of the face and neck, giving it the distinctive 'hamster face' appearance.2
The skin can be hot and flushed, but there is no rash. The infection is also commonly associated with pain near the angle of the jaw, dry mouth, and reduced opening of the mouth.
Mumps is a contagious viral infection that can cause fever, neck pain and swelling. It is usually a clinical diagnosis, however confirmation, via a salivary sample, is required as it is a notifiable disease. The MMR (measles, mumps and rubella) vaccine is part of the national immunisation programme and the efficacy of both doses against mumps is 88%.
High fever, neck pain and swelling can also be caused by other infections including pharyngitis, tonsillitis, infectious mononucleosis and HIV. Parotid stones can also cause pain and swelling but are usually unilateral and occur in older patients. Unilateral testicular swelling and pain can be caused by testicular torsion and bilateral testicular swelling should prompt consideration of epididymo-orchitis caused by sexually transmitted infections. Meningitis and encephalitis can be caused by other infectious (viral, bacterial, fungal) and non-infectious (neoplastic) agents.
If patients present with meningitis or encephalitis further investigations are required to look for other causes.
Mumps is a self-limiting condition and most children recover within one to two weeks. Supportive management may include simple analgesia, advice regarding fluid intake and rest. Admission to hospital is required if there are concerns about complications. Children should not attend school for five days following the development of parotitis. If a person is exposed to mumps and has not been fully immunised, MMR should be offered in the absence of contraindications.
Mumps orchitis often occurs without parotitis, but if both are present, orchitis generally develops four or five days after the parotitis onset. Orchitis is found in 25% of post-pubertal males with mumps and is bilateral in 15-30% of cases. It is associated with severe testicular pain and tenderness and significant scrotal oedema may make the testes impalpable.
Bilateral orchitis may lead to subfertility.
Mumps meningitis and encephalitis usually occur without parotitis.
In patients infected with the mumps virus, 15% develop meningism.
Mumps encephalitis is rare and may present as part of the initial infection or later in the course of the disease. It has a mortality rate of 1.5%.
Other complications include oophoritis, deafness (usually unilateral and transient), and pancreatitis.
Pathology: Paramyxo virus causing parotitis (‘mumbling’ due to parotid gland infection).
Aetiology: Droplet transmission. Preventable by MMR Vaccine (15 months).
Symptoms: Fever, headache,orchitis.
Signs: Parotid swelling.
Investigations: Clinical diagnosis
Treatment: Conservative: Supportive and analgesia
Complications: Meningitis,pancreatitis, orchitis, sub-fertility.
Prognosis: Often resolves within 1 to 2 weeks.
Most patients recover without any long term complications.
