Mumps: Symptoms, Causes, Complications, and Prevention

Overview

Mumps is a contagious viral illness best known for causing painful swelling of the salivary glands, especially the parotid glands located below and in front of the ears. This swelling often creates the classic “chipmunk cheeks” or swollen jaw that makes the disease recognizable. While many cases are mild and resolve on their own, mumps can occasionally lead to serious complications.

Before the vaccine was introduced in 1967, mumps was a common childhood disease worldwide. Since then, routine immunization has drastically reduced the number of cases. However, outbreaks still occur, especially in crowded environments like schools, dormitories, and camps. People who are not vaccinated remain at the highest risk, but even vaccinated individuals may develop milder infections if their immunity has waned.

There is no specific cure for mumps. Treatment focuses on managing symptoms until the illness runs its course. Fortunately, vaccination remains the most effective way to prevent both infection and the spread of the virus.

Causes and Transmission

Mumps is caused by the mumps virus, a member of the paramyxovirus family. It spreads much like the flu or the common cold — through respiratory droplets, saliva, or direct contact with an infected person. When someone with mumps coughs, sneezes, talks, or shares items such as cups or utensils, the virus can easily pass on.

The virus can also linger on surfaces or in the air for up to two hours, making it highly contagious. Close-contact settings such as classrooms, sports teams, or dormitories are particularly vulnerable to outbreaks.

The incubation period — the time between exposure and when symptoms appear — ranges from about 12 to 25 days. A person with mumps can be contagious from several days before gland swelling begins until roughly five days afterward. Alarmingly, up to one-third of infected people never develop noticeable symptoms but can still spread the virus to others.

Symptoms

Mumps symptoms vary widely. Some people may not experience any at all, while others develop a range of flu-like complaints followed by the characteristic swelling of the salivary glands.

Early symptoms often resemble a common viral illness and may include fever, fatigue, headache, muscle aches, sore throat, loss of appetite, and general weakness.

Within a few days, the hallmark sign appears: swelling of one or both parotid glands, causing puffy cheeks and a tender jaw. This swelling, known as parotitis, occurs in most symptomatic cases and may make chewing and swallowing painful.

Other possible symptoms include ear pain, mild abdominal discomfort, dry mouth, or joint pain. In men, orchitis — inflammation of one or both testicles — can cause swelling and severe pain. In women, oophoritis, or ovarian inflammation, may occur, often causing nausea and fever.

Mumps usually lasts about two weeks, though fatigue and mild discomfort may persist longer. Most children and adults recover fully without lasting effects, but complications can occur.

Mumps in Adults and Pregnancy

Although mumps is more common in children, adults can also contract the virus. In adults, the disease is often more severe and more likely to result in complications such as orchitis, oophoritis, or even meningitis.

During pregnancy, mumps usually doesn’t harm the baby, but in rare cases, it may increase the risk of miscarriage, premature birth, or low birth weight, particularly if the infection occurs in the first trimester. Pregnant individuals who suspect exposure to mumps should consult their healthcare provider immediately.

Babies under one year are rarely infected because they retain some protective antibodies from their mother during pregnancy. However, this protection fades, which is why vaccination is crucial after the age of 12 months.

Complications

While many cases of mumps are mild, the infection can spread to other parts of the body and cause more serious health problems. Complications are more likely in unvaccinated people and in adults. These may include:

• Orchitis (testicular inflammation): Painful swelling that may reduce fertility in rare cases.
• Oophoritis (ovarian inflammation): Can mimic appendicitis and cause fever, nausea, and abdominal pain.
• Mastitis (breast tissue inflammation): Less common today due to vaccination.
• Pancreatitis: Inflammation of the pancreas, leading to abdominal pain, fever, and vomiting.
• Meningitis: Inflammation of the protective membranes around the brain and spinal cord, sometimes causing severe headache and neck stiffness.
• Encephalitis: A rare but life-threatening brain inflammation that can cause seizures, coma, or long-term neurological damage.
• Hearing loss: Temporary or permanent hearing loss may occur in some cases.

Although rare, mumps-related complications can be life-threatening, making prevention through vaccination extremely important.

Diagnosis

Doctors typically diagnose mumps by taking a detailed medical history, examining swollen salivary glands, and looking for telltale signs such as parotitis or Koplik spots inside the mouth. In uncertain cases, laboratory tests may be used, such as a throat swab, PCR testing, or blood tests to confirm the presence of the virus.

Treatment

There is no specific antiviral treatment for mumps. The illness usually resolves on its own within a couple of weeks, but supportive care can help ease symptoms and prevent complications.

Recommended measures include plenty of rest, hydration, and the use of over-the-counter pain relievers such as acetaminophen or ibuprofen to reduce fever and discomfort. Applying cold or warm compresses to swollen glands, eating soft foods, and avoiding acidic beverages can help ease pain while chewing or swallowing.

For men with orchitis, supportive care such as ice packs and scrotal support can relieve discomfort. In rare cases of severe complications like meningitis or encephalitis, hospitalization may be required.

Children should never be given aspirin during viral illnesses such as mumps, as it has been linked to Reye’s syndrome, a potentially life-threatening condition.

Prevention

The best protection against mumps is vaccination. The measles, mumps, and rubella (MMR) vaccine is highly effective, preventing infection in up to 90% of people who receive both recommended doses. Children should receive their first dose at 12–15 months of age and a second dose at 4–6 years of age.

In some cases, such as during outbreaks, public health authorities may recommend a third dose to improve immunity.

The vaccine is safe for the vast majority of people. Side effects, when they occur, are usually mild, such as fever, rash, or temporary soreness at the injection site. Serious side effects are extremely rare. Importantly, despite persistent myths, extensive scientific research has shown no link between the MMR vaccine and autism.

Beyond vaccination, basic hygiene practices help reduce the spread of mumps. Frequent handwashing, avoiding sharing cups or utensils, and covering coughs and sneezes are simple but effective measures. Infected individuals should stay home and avoid close contact with others for at least five days after symptoms begin.

Outlook

For most children and adults, mumps is a temporary illness that resolves without lasting harm. Once a person has had mumps, they usually gain lifelong immunity. However, because of the potential for complications — particularly in adults and pregnant individuals — prevention remains the best strategy. Thanks to widespread vaccination, mumps is far less common today than it was decades ago. Still, outbreaks can and do occur, especially in communities with lower vaccination coverage. Keeping immunizations up to date not only protects individuals but also prevents the virus from spreading within families, schools, and communities.