Mumps is a viral infection that causes swelling in the salivary glands

Mumps is an infection caused by the mumps virus, which spreads through respiratory droplets—the tiny particles released when an infected person coughs, sneezes, or talks. The hallmark sign is swelling of the parotid glands, the salivary glands located on both sides of the face just below and in front of the ears. This swelling makes the cheeks puff out noticeably and is often tender to the touch.

The infection typically starts with general symptoms like fever, headache, and body aches, similar to a cold or flu. Within a few days, the characteristic gland swelling appears. Most people recover on their own within one to two weeks, though some complications can develop, particularly in adults.

Mumps was once common in children before the MMR vaccine became standard. Today it is rare in countries with high vaccination rates, but outbreaks still occur in communities where vaccination coverage is lower or among unvaccinated people who travel to areas where mumps is still circulating.

Key Takeaways

  • Mumps causes swelling of the salivary glands on the sides of the face, along with fever and body aches.
  • The virus spreads through respiratory droplets when an infected person coughs, sneezes, or talks, and is contagious for about a week before symptoms appear through a week after.
  • Most people recover without treatment in one to two weeks, but adults and people with weakened immune systems face higher risk of serious complications.
  • The MMR vaccine prevents mumps in about 88 percent of people who receive two doses, and is the most effective way to avoid infection.

How the mumps virus spreads from person to person

Mumps spreads when respiratory droplets from an infected person enter another person's nose or mouth. This happens most easily in close settings—classrooms, offices, shared housing—where people spend time near each other. A person can spread mumps starting about a week before their glands swell and continuing for about a week after the swelling begins.

The virus can also spread through contact with saliva, though this is less common. Sharing utensils, cups, or toothbrushes with someone who has mumps increases the risk. Once someone has had mumps, they develop lifelong immunity to the virus—they cannot catch it again.

Symptoms appear gradually over several days

The first symptoms of mumps are often mistaken for a common cold or flu. They include fever, headache, muscle aches, fatigue, and loss of appetite. These symptoms typically last two to three days before the characteristic gland swelling appears.

When the parotid glands swell, the swelling is usually on both sides of the face, though it can start on one side and spread to the other. The swelling is tender and makes chewing or swallowing painful. Some people also develop swelling of the submandibular glands, located under the jaw. The gland swelling peaks around day three or four and gradually subsides over the next week or two.

Not everyone with mumps develops obvious gland swelling—some people have mild or no symptoms at all, even though they carry the virus and can spread it to others. This is one reason mumps can spread in communities where people assume they are not at risk.

Complications are rare in children but more common in adults

Most children recover from mumps without any lasting problems. However, mumps can lead to serious complications in some people, particularly adults and those with weakened immune systems.

Meningitis—inflammation of the membrane surrounding the brain and spinal cord—is the most common serious complication. It occurs in roughly 1 to 10 percent of mumps cases and causes severe headache, stiff neck, and sensitivity to light. Most people recover fully, though recovery takes longer than uncomplicated mumps.

Encephalitis, inflammation of the brain itself, is rarer but more serious. Deafness can develop suddenly during mumps infection and may be permanent. Mumps can also cause inflammation of the testicles in males and the ovaries in females, though this rarely leads to infertility. Pancreatitis—inflammation of the pancreas—can occur but is usually mild.

Adults who contract mumps face higher risk of these complications than children do. Pregnant people who contract mumps in the first trimester may have an increased risk of miscarriage, though mumps does not cause birth defects.

Diagnosis relies on symptoms and sometimes blood tests

A doctor typically diagnoses mumps based on the characteristic swelling of the salivary glands combined with fever and the patient's vaccination history or exposure to someone with mumps. In straightforward cases, no additional testing is needed.

When diagnosis is uncertain or when complications are suspected, a blood test can confirm mumps by detecting antibodies to the virus or by identifying the virus itself. A saliva or cerebrospinal fluid sample may be taken if meningitis is suspected. These tests are most useful early in the illness, when the virus is still present in high amounts.

Treatment focuses on managing symptoms while the body fights the infection

There is no antiviral medication that kills the mumps virus. Treatment consists of supportive care—measures that help the body fight the infection and ease discomfort while the immune system clears the virus.

Over-the-counter pain relievers like acetaminophen or ibuprofen can reduce fever and ease headache and muscle aches. Applying ice or heat to the swollen glands may provide comfort. Eating soft foods and drinking plenty of fluids helps maintain nutrition and hydration when swallowing is painful. Rest allows the body to direct energy toward fighting the infection.

People with mumps should stay home and avoid close contact with others for at least five days after the gland swelling begins, to prevent spreading the virus. Anyone with symptoms suggesting complications—severe headache, stiff neck, confusion, or hearing loss—should seek medical care promptly.

The MMR vaccine prevents mumps in most vaccinated people

The MMR vaccine, which protects against measles, mumps, and rubella, is the most effective way to prevent mumps. Two doses of the vaccine prevent mumps in approximately 88 percent of people who receive both doses. A single dose provides roughly 78 percent protection.

The vaccine is a live attenuated virus, meaning it contains a weakened form of the mumps virus that triggers immunity without causing disease. It is given as an injection, typically at 12 to 15 months of age and again at 4 to 6 years old, though the second dose can be given as soon as 28 days after the first.

The vaccine does not provide perfect protection—some vaccinated people still contract mumps if exposed, particularly if they received only one dose. However, vaccinated people who do get mumps typically have milder illness with less risk of complications. People born before 1957 are generally considered immune because mumps was widespread then, though immunity can wane over time.

Frequently Asked Questions

Can you catch mumps twice?

No. Once you have had mumps, your immune system develops lifelong immunity to the virus. You cannot catch it again. However, if you were vaccinated but never had mumps, you could still contract it if exposed, since vaccine protection is not absolute.

Is mumps contagious before the glands swell?

Yes. A person can spread mumps starting about a week before the glands swell, when they may only have fever and body aches that seem like a cold. This is why mumps can spread before anyone realizes what illness is circulating.

What should I do if I think I have mumps?

Contact your doctor to confirm the diagnosis. Stay home and avoid close contact with others for at least five days after the gland swelling begins. Use over-the-counter pain relievers for discomfort, eat soft foods, and drink plenty of fluids. Seek immediate care if you develop severe headache, stiff neck, confusion, or sudden hearing loss.

Can adults get mumps if they were vaccinated as children?

Vaccinated adults have strong protection, but breakthrough infections can occur, especially if they received only one dose or if immunity has waned over decades. Adults who are unsure of their vaccination status can ask their doctor about a booster dose before traveling to areas where mumps is circulating.

How long does it take to recover from mumps?

Most people recover within one to two weeks. The fever and body aches usually improve within a few days, while gland swelling peaks around day three or four and gradually subsides over the next week or two. Fatigue may linger longer. Complications like meningitis extend recovery time significantly.