Introduction

Although many people see mumps as an infection of the past, recently there has been a steady rise in cases which hit a decade high in 2019. Mumps is a viral infection most commonly recognisable by the distinctive swollen and puffy cheeks, resembling a hamster, that it causes. 

Droplets of infected saliva that are inhaled or picked up from surfaces spread the disease from one person to another. A person is at their most contagious a little before symptoms appear until a little while afterwards. 

Common symptoms include fever, swollen glands, headache and pain in the joints. The array of symptoms indicates that once a person is infected with a viral load via the respiratory tract, the virus spreads out and infects other regions.¹ In the parotid salivary glands the virus replicates resulting in the characteristic painful swelling. 

Most patients with cases of mumps will overcome the infection on their own. However, in some rare cases, severe complications can develop. Such complications may include meningitis, pancreatitis, encephalitis (swelling of the brain), swelling of the testicles and ovaries (in post-pubescent young adults), and loss of hearing in children. 

In 1988 the MMR (measles, mumps and rubella) vaccine was introduced in the UK.² The vaccine proved to be effective as in the first decade after its introduction cases of mumps slumped to record low levels.² 

Mumps, unlike smallpox, isn’t an extinct infection of the past. Therefore recognising the signs and symptoms can be crucial when an infection is suspected.

Symptoms and diagnosis

Following the initial infection of the mumps virus, the first symptoms take around one to three weeks to show and are often mild. The long incubation period is responsible for this delay in noticeable symptoms. The first symptoms may include:

• Fever
• Headache
• Muscle aches 
• Fatigue 
• Loss of appetite 

Occurring a few days after the initial signs, the most common symptom and recognisable symptom of mumps begin to show. The swelling of the parotid glands (parotitis), occurs in approximately 70% of cases.³ Typically, the swelling occurs bilaterally (on both sides of the face) and can be very painful. Parotitis usually lasts around a week, when caused by mumps, and you should see a doctor to confirm the cause of the swelling. 

In around 40% of mumps cases in post-pubescent young men, orchitis (swelling of the testicles) will be experienced.⁴ During the acute phase of the infection, hormone profiles will be affected which may include decreased testosterone. Hormone levels quickly recover following the illness, however, an abnormal shape of the testes may remain. Furthermore, studies have shown chronic abnormalities in semen following orchitis caused by mumps.⁴ Many assigned male at birth (AMAB) people may experience infertility as a result of these abnormalities. 

A healthcare provider may be able to diagnose mumps by examining your child’s clinical history and carrying out a physical examination. Laboratory tests may also be used to diagnose mumps. A buccal swab (a swab inside their mouth) will be sent to the labs where scientists will perform an RT-PCR analysis to determine whether the virus is present. 

Complications

Although rare, cases of mumps can lead to severe complications in children, including meningitis, pancreatitis, hearing loss and encephalitis. 

Meningitis

If the virus spreads to the outer layers of the brain (meninges) it may cause inflammation. The inflammation of the meninges is called meningitis. Symptoms of viral meningitis include:

• Light sensitivity 
• A stiff neck
• Headache
• Fever

Viral meningitis usually doesn’t require hospitalisation and usually clears up on its own in approximately 1-2 weeks.  

Staying hydrated, taking painkillers and resting can aid in the relief of the symptoms. 

Pancreatitis

The pancreas is an organ located in your abdomen, just behind the stomach. It secretes enzymes to aid in digestion and also produces the hormones insulin and glucagon which stabilise blood sugar levels. 

In approximately 1 in 25 cases of mumps, acute pancreatitis develops. The inflammation of the pancreas causes a sudden severe pain around the centre of the abdomen. Other symptoms include:

• Nausea and vomiting
• High fever
• Loss of appetite
• Diarrhoea

Patients with acute pancreatitis are usually admitted to hospital to help manage the symptoms. Management often involves IV fluids, pain relief and liquid food.⁵ 

Hearing loss

Temporary hearing loss is reported to occur in 1 in 25 cases, whilst long-term hearing loss is much rarer at approximately 1 in 20,000 cases. 

Typically, the hearing loss occurs on one side (unilaterally) and is reversible, however, it may be permanent. Proposed mechanisms of hearing loss include loss of hair cells in the cochlea (part of the ear) and damage to the myelin sheath that surrounds the vestibulocochlear nerve.⁶  

Encephalitis 

Inflammation of the brain is called encephalitis. It is a serious life-threatening condition and requires urgent medical attention. Around 1 in 1000 cases of mumps lead to encephalitis. Symptoms include:

• Fever
• Headache
• Seizure
• Weakness in the body 
• Speech difficulty
• Loss of consciousness

Treatment and management

Unfortunately, there is no cure for mumps, but the infection usually passes in around 1-2 weeks in most people. 

To relieve the symptoms associated with mumps you can:

• Rest 
• Stay hydrated
• Keep a warm or cool compress on your swollen glands 
• Take over the counter painkillers like paracetamol and ibuprofen

Do not give aspirin to your child as it is linked to a serious condition called Reye's syndrome. 

Prevention

Vaccination

In 1949 the MMR vaccine was introduced in the UK and has since significantly reduced the prevalence of mumps. The first dose of the vaccine is offered to infants between the age of 12 and 15 months. A second dose is given between 3 and 6 years of age. A third booster dose is offered to late teens/young adults (17-21 years of age).⁶ 

The vaccine contains a live attenuated version of the virus, therefore it is not recommended for highly immunocompromised individuals.⁶ 

After 2-weeks from the second dose, the NHS approximates that 88% of children are protected against mumps. Those who have been vaccinated, but still develop the condition, often display milder symptoms than unvaccinated individuals. 

Quarantine and Isolation

Mumps is spread through contact with infected saliva via coughing, sneezing and touching infected surfaces. To help prevent outbreaks of mumps, individuals who have been diagnosed should quarantine and isolate to help prevent the spread of the virus. 

Measures to be taken include:

• Stay at home for at least 5 days from when your symptoms start
• Regularly wash your hands with soap
• Dispose of the tissues used to blow your nose and sneeze
• Avoid close contact with others

Frequently Asked Questions (FAQs)

What is mumps?

Mumps is a very contagious viral infection which used to be very common in children. 

Why is mumps not as common as it used to be?

In 1949 the MMR vaccine was introduced to the UK. The vaccine was incredibly effective at reducing the prevalence of mumps. 

What is the most common symptom?

Swelling of the parotid glands in your face is the most common tell-tale sign of mumps. 

Are there other symptoms of mumps other than swollen glands?

Yes, other symptoms include fever, headaches, body aches, fatigue and loss of appetite.  

How is mumps diagnosed?

A physical examination and medical history can be used in a diagnosis. Also, a swab of your mouth can confirm the presence of the virus. 

Are there any complications associated with mumps?

Complications include viral meningitis, encephalitis, pancreatitis and hearing loss. 

How are mumps treated?

There is no cure for mumps. Treatment aims to relieve the symptoms. Rest, hydration and painkillers (such as paracetamol and ibuprofen) are helpful. 

When should I see a doctor?

If you suspect a case of mumps, you should contact your GP as soon as possible. They can confirm the diagnosis and rule out other infections. Changes in your symptoms or worsening of symptoms also warrant advice from a medical professional. 

Conclusion

To conclude, since the introduction of the MMR vaccine to the UK in 1949, outbreaks of mumps have declined significantly. In recent years, due to a decrease in uptake of the vaccine, the frequency of mumps outbreaks has increased. 

The tell-tale sign of a mumps infection is the swollen parotid glands which give the face a puffy appearance. Other symptoms include fever, loss of appetite, muscle aches, headache and tiredness. In most cases, recovery will take around 1 to 2 weeks and won’t require hospitalisation. Treatment involves relieving the symptoms of the infection through rest, painkillers and a warm/cold compress on the swollen glands.

In some cases, rare complications may develop. These include viral meningitis, encephalitis, pancreatitis and hearing loss. 

The MMR vaccine is the best way to help prevent contracting the virus. If you believe you may be infected with mumps you should isolate yourself to stop the spread.