Mumps is a contagious illness caused by a virus that mainly affects the salivary glands, especially the parotid glands located near the jaw. In more serious cases, it can also affect other parts of the body. The virus spreads through tiny droplets in the air when an infected person coughs, sneezes, or talks, and can also be passed on by touching contaminated surfaces. After infection, it usually takes about 16–18 days for symptoms to appear, but a person can spread the virus before showing any signs of illness.
Common symptoms include painful swelling of one or both parotid glands, fever, headache, muscle aches, tiredness, and loss of appetite. Some people, particularly those who have been vaccinated, may have only mild symptoms or none at all but can still spread the virus. If not treated promptly, mumps can sometimes cause complications such as inflammation of the testicles (orchitis), ovaries (oophoritis), or pancreas (pancreatitis), as well as meningitis, encephalitis, or permanent hearing loss.
There is no specific medicine to cure mumps. Treatment focuses on easing symptoms such as pain and fever—keeping hydrated, and getting enough rest. People with mumps are usually advised to stay away from others for several days before and after their glands swell to help prevent the spread of the disease.
The most effective way to prevent mumps is through vaccination, usually given as part of the measles, mumps, and rubella (MMR) vaccine or the measles, mumps, rubella, and varicella (MMRV) vaccine. Widespread vaccination programs have greatly reduced the number of mumps cases worldwide, although outbreaks can still happen in areas with low vaccination rates or waning immunity.
History and Epidemiology
Mumps is one of the oldest known diseases, recorded as early as the 5th century B.C. by the Greek physician Hippocrates, who described swelling near the ears—now recognized as a typical symptom. In the 18th century, British doctor Robert Hamilton gave the first detailed medical description, identifying mumps as a distinct illness.
It was not until 1934 that scientists proved mumps was caused by a virus. Researchers showed that saliva from infected people could spread the disease to rhesus monkeys. The virus itself was isolated in 1945, and by 1948, the first mumps vaccine was created. However, this early vaccine offered only short-term protection.
A major breakthrough came in 1967, when Maurice Hilleman developed a stronger, long-lasting vaccine from the “Jeryl Lynn” strain of the virus. This remains the strain used today in the combined measles–mumps–rubella (MMR) vaccine. The MMR vaccine was introduced in 1971, and the two-dose schedule became standard worldwide in the 1980s.
Epidemiological Trends and Outbreaks
Before vaccines, mumps was very common, with outbreaks every 2–5 years, mostly in children aged 5–9. Infection rates could range from 100 to 1,000 cases per 100,000 people each year.
Widespread vaccination caused a dramatic drop in cases. In the United States, numbers fell from over 152,000 in 1968 to just 231 in 2003—a reduction of more than 99%. Similar success was seen in places like Vojvodina, Serbia, where rates fell from hundreds per 100,000 people to fewer than 0.5 by 2024.
Despite high vaccination coverage, mumps outbreaks still occur, often in adolescents and young adults who spend time in crowded settings such as schools, colleges, or military facilities. Examples include a U.S. college outbreak in 2006 with over 6,500 cases, and a Jerusalem outbreak in 2009–2010 with more than 3,400 cases. Factors such as waning immunity (weakened vaccine protection over time), incomplete vaccine effectiveness, and changes in the virus may contribute.
As of mid-2025, the U.S. had reported 182 mumps cases across 32 states and territories. Health officials note that even vaccinated people can catch mumps if their immunity has weakened and they are not regularly exposed to the virus in the environment, which can naturally boost protection.
In Vojvodina, mumps were common in the late 20th century, with rates reaching up to 706 per 100,000 people. After vaccination was introduced, cases fell sharply. Occasional small outbreaks occurred, such as in 2012, but between 2014 and 2024 the rate remained below 0.5 per 100,000, mostly affecting children and teenagers.
Causes of Mumps
Mumps results from infection by a specific virus and is spread primarily through close contact. Several factors increase the likelihood of transmission, and the infection follows a defined incubation timeframe before symptoms appear.
Mumps Virus and Transmission
The mumps virus spreads predominantly through respiratory droplets released when an infected person coughs, sneezes, or speaks. These droplets can be inhaled directly by nearby individuals or can contaminate surfaces and objects.
Although the virus can survive briefly—usually minutes to hours—on surfaces such as doorknobs, utensils, or cups, transmission by this route is far less common than through direct droplet inhalation. Close contact activities that involve the exchange of saliva, such as sharing eating or drinking utensils, increase the likelihood of infection.
Crowded or poorly ventilated indoor environments, including classrooms, dormitories, and public transport, significantly amplify the risk of airborne transmission, as viral particles remain suspended in the air for short distances. After entering the body, the virus typically infects cells of the upper respiratory tract and multiplies locally before spreading via the lymphatic system and bloodstream to other tissues.
Risk Factors
The primary risk factor for contracting mumps is direct exposure to an infected person, particularly during the period when the virus is most transmissible—approximately two days before and up to five days after the onset of salivary gland swelling. Historically, mumps was most common in children between the ages of five and nine.
However, in countries with widespread vaccination, outbreaks are now more frequently observed among adolescents and young adults, particularly in environments where individuals live or interact in close quarters, such as universities, boarding schools, sports teams, and military barracks.
Vaccination status is a critical determinant of susceptibility. Individuals who are unvaccinated or who have received only one dose of a mumps-containing vaccine, such as the measles, mumps, and rubella (MMR) vaccine, are at higher risk of infection. Even fully vaccinated individuals may become infected during outbreaks due to waning immunity, especially if their last vaccine dose was administered many years earlier.
Other contributing factors include living in crowded, unhygienic conditions, traveling to regions experiencing active outbreaks, and participating in events or gatherings where many people are in close contact.
Incubation Period
The incubation period for mumps generally ranges from 16 to 18 days, but it can vary from as few as 12 days to as many as 25 days after initial exposure. During this time, the infected individual typically does not exhibit symptoms, yet viral replication and shedding may already be occurring. Asymptomatic transmission is a notable feature of mumps epidemiology, with viral shedding often beginning one to two days before the onset of symptoms. This silent infectious period complicates outbreak control efforts because individuals may unknowingly spread the virus before they realize they are ill.
Viral shedding typically continues for several days after the onset of parotid gland swelling, meaning that infected individuals remain contagious well into the symptomatic phase. This prolonged window of infectivity, combined with the potential for asymptomatic or mild cases to go undetected, contributes to the persistence of mumps in communities, even in regions with high vaccination coverage.
Symptoms of Mumps
Mumps presents with distinct physical signs and a progression of symptoms that can vary among individuals. Some symptoms appear early, while others develop as the infection affects specific glands or leads to complications.
Early Signs and Symptoms
The initial phase of mumps, known as the prodromal stage, generally occurs after an incubation period of about 16 to 18 days following exposure, although symptoms can appear as early as 12 days or as late as 25 days.
During this stage, patients often develop nonspecific symptoms such as low- to moderate-grade fever, headache, muscle aches (myalgia), fatigue, and loss of appetite (anorexia). Mild respiratory manifestations, such as a sore throat or a dry cough, may also occur.
Because these early symptoms are common to many viral illnesses, including influenza and other respiratory infections, diagnosis at this stage can be difficult without confirmatory testing. The prodrome typically lasts one to two days before the onset of the hallmark symptom—salivary gland swelling.
Parotitis and Swollen Glands
The most distinctive and classic sign of mumps is parotitis, or inflammation of the parotid glands, which are the largest of the salivary glands and are located just below and in front of each ear along the jawline.
Parotitis usually develops rapidly, often first affecting one side of the face (unilateral swelling) before spreading to both sides (bilateral swelling) within 24 to 48 hours. This swelling can cause visible puffiness in the cheeks and jaw, producing the characteristic “chipmunk” appearance. The affected area is typically tender to the touch, and patients often experience pain when chewing, swallowing, or consuming acidic beverages.
While the parotid glands are most commonly affected, other salivary glands including the submandibular and sublingual glands may also become inflamed, causing additional facial swelling and discomfort.
Swelling typically persists for 7 to 10 days, with the intensity of pain and tenderness gradually decreasing as the illness progresses. In some cases, gland swelling may be minimal or even absent, particularly in vaccinated individuals, which can make recognition of mumps more challenging.
Complications From Infection
Although mumps is often self-limiting, it can occasionally cause serious complications, particularly in unvaccinated individuals and in post-pubertal males and females. One of the most well-known complications in males is orchitis, an inflammation of one or both testicles that typically develops four to eight days after the onset of parotitis. Orchitis presents with swelling, tenderness, and redness of the scrotum, often accompanied by high fever. While most patients recover fully, severe cases can result in testicular atrophy and, rarely, infertility.
In females, mumps can cause oophoritis, an inflammation of the ovaries, which may result in lower abdominal pain, fever, and tenderness. Although oophoritis does not typically lead to infertility, it can cause significant discomfort.
Neurological complications include aseptic meningitis, which presents with headache, neck stiffness, nausea, vomiting, and sensitivity to light (photophobia), and, less commonly, encephalitis, which can cause confusion, seizures, and, in rare instances, permanent neurological damage. Other recognized but less frequent complications are pancreatitis, characterized by abdominal pain, nausea, and elevated pancreatic enzyme levels, and sensorineural hearing loss, which may be temporary or, in rare cases, permanent.
Disease Progression
The course of mumps typically spans about 10 days, although the severity and duration of symptoms can vary. After the onset of parotid swelling, fever and discomfort generally peak within the first few days, followed by gradual improvement. Most patients recover completely, and the infection usually confers lifelong immunity.
However, fatigue and mild joint pain can persist for several weeks after the acute phase, especially in adults. Importantly, individuals with mumps can be infectious from approximately two days before the onset of gland swelling until about five days afterward. This window of viral shedding—combined with the possibility of asymptomatic or minimally symptomatic cases
Diagnosing Mumps
Diagnosing mumps relies on evaluating physical signs alongside specific laboratory tests. The process rules out other conditions with similar symptoms to ensure accurate identification. Clinical features, lab results, and differential considerations all play a key role.
Clinical Assessment
A thorough medical history and physical examination are the first steps in diagnosing mumps. The hallmark clinical finding is swelling and tenderness of the parotid glands, which are situated just in front of and below the ears. The swelling may be unilateral at first but often becomes bilateral within a short period. Patients commonly report pain during chewing, swallowing, or drinking acidic beverages. Associated symptoms, such as fever, headache, muscle aches, and fatigue, provide supportive evidence for the diagnosis.
The clinician will also inquire about recent contact with individuals known to have mumps, as well as the patient’s vaccination history, since unvaccinated individuals are at greater risk. In vaccinated individuals, gland swelling may be less pronounced or absent, which can make clinical diagnosis more challenging. The timing of symptom onset, typically 16 to 18 days after exposure, also helps narrow the diagnostic possibilities. Other findings during examination may include jaw pain, earache, or swelling of other salivary glands such as the submandibular or sublingual glands.
Laboratory Testing
Laboratory confirmation is essential, particularly in outbreak situations, atypical cases, or vaccinated individuals who may present with mild or absent parotid swelling. The most widely used diagnostic test is the detection of mumps virus-specific immunoglobulin M (IgM) antibodies in the blood. The presence of IgM generally indicates recent infection; however, it may not be detectable in the first few days of illness, and in previously vaccinated individuals, IgM responses may be weak or absent.
Polymerase chain reaction (PCR) testing from a buccal or oral swab is now considered the most sensitive and specific method for confirming mumps. PCR detects the genetic material (RNA) of the virus and is most effective when samples are collected within the first three days after the onset of gland swelling, although it can remain positive for up to a week. Viral culture, once a common method, is now rarely used in clinical practice because it is time-consuming and less sensitive than PCR.
Supportive laboratory findings may include elevated serum amylase levels, which result from inflammation of the salivary glands. While this finding is not specific to mumps and can occur in other conditions such as pancreatitis, it can provide additional evidence when interpreted alongside other test results. In practice, combining serological testing with PCR greatly increases diagnostic accuracy.
Differential Diagnosis
Because several infectious and non-infectious conditions can mimic the presentation of mumps, differential diagnosis is a crucial part of the evaluation. Bacterial sialadenitis, often caused by Staphylococcus aureus, can produce parotid swelling but is usually accompanied by localized redness, purulent discharge from the salivary duct, and more severe systemic symptoms such as high fever and chills. Other viral infections, including Epstein–Barr virus (infectious mononucleosis), cytomegalovirus, adenovirus, and influenza, can cause gland swelling but often have distinguishing features; for example, infectious mononucleosis commonly presents with pronounced lymph node enlargement, sore throat, and atypical lymphocytes on a blood smear.
Non-infectious causes must also be considered. Obstruction of a salivary duct by a stone (sialolithiasis) can cause intermittent gland swelling, usually associated with meals, and tends to be localized rather than bilateral. Tumors of the salivary glands, while less common, may produce chronic, painless swelling and should be excluded through imaging and further specialist evaluation when appropriate.
Distinguishing mumps from these conditions requires careful correlation of the patient’s symptoms, physical examination findings, laboratory results, and history of exposure.
Treatment Options for Mumps
Treatment for mumps focuses on relieving symptoms and preventing complications, as there is no specific antiviral therapy. Care strategies include managing pain, fever, and ensuring proper rest and hydration.
Supportive Care Measures
Supportive care forms the foundation of mumps management. Adequate rest allows the immune system to combat the infection more effectively, while maintaining proper hydration helps replace fluids lost through fever or reduced appetite. Patients are advised to consume soft foods and avoid acidic or sour substances, such as citrus fruits and juices, which can increase salivary flow and cause pain in swollen glands. Cold or warm compresses applied to the swollen parotid region can help relieve discomfort, with some patients preferring the soothing effect of warmth while others benefit from cold applications to reduce inflammation.
Good oral hygiene is also important, as it helps reduce the risk of secondary bacterial infections in the oral cavity. Gentle toothbrushing and rinsing with a mild antiseptic mouthwash may be recommended. To prevent transmission, infected individuals should remain in isolation from the onset of gland swelling until at least five days afterward, as this is the period of greatest infectiousness. In household settings, separate eating utensils, cups, and towels should be used, and frequent handwashing should be practiced by both the patient and caregivers.
Pain and Fever Management
Pain and fever associated with mumps can usually be managed with over-the-counter medications. Acetaminophen (paracetamol) or nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen are commonly recommended to reduce discomfort and lower fever. These medications should be taken according to the correct dosage for the patient’s age and weight to avoid potential side effects. Aspirin should not be given to children or adolescents due to the risk of Reye’s syndrome, a rare but potentially life-threatening condition that can cause swelling in the liver and brain.
Monitoring the progression of symptoms is essential. If fever persists beyond a few days, swelling becomes markedly worse, or new symptoms such as severe headache, stiff neck, abdominal pain, or hearing changes develop, medical evaluation should be sought promptly, as these may indicate complications.
Hospitalization Criteria
Hospital admission for mumps is uncommon but may be necessary when severe or potentially life-threatening complications occur. These include aseptic meningitis or encephalitis, which present with neurological symptoms such as confusion, seizures, or altered consciousness; severe dehydration resulting from prolonged vomiting or inability to eat or drink; or orchitis complicated by testicular torsion, which requires urgent surgical assessment to preserve testicular function.
Infants, immunocompromised individuals, and pregnant women, particularly those in the first trimester are considered high-risk and may require closer monitoring or hospital care due to the potential for more severe illness or complications. In a hospital setting, treatment may include intravenous fluids for hydration, stronger pain control measures, antiemetic medications to control vomiting, and close neurological observation. In rare cases, imaging or specialist consultation is required to rule out other causes of symptoms.
Preventing Mumps
Mumps prevention relies primarily on vaccination and adherence to public health guidelines. Since there is no specific antiviral treatment for mumps, stopping the disease before it spreads is the most effective control strategy.
MMR Vaccination
The measles, mumps, and rubella (MMR) vaccine is the cornerstone of mumps prevention. In some countries, a combined measles, mumps, rubella, and varicella (MMRV) vaccine is used. The vaccine contains live attenuated viruses, meaning the viruses are weakened so they can trigger immunity without causing full-blown illness.
Administration schedule:
- First dose: 12–15 months of age
- Second dose: 4–6 years of age
- In certain outbreak situations or in communities with low vaccination rates, a third dose may be recommended to boost immunity.
Effectiveness:
- Two doses of MMR provide about 88% effectiveness in preventing mumps, while one dose offers around 78% protection.
- Immunity can wane over time, which is why booster doses during outbreaks have been shown to reduce the spread in high-risk environments, such as universities, military barracks, and other crowded settings.
Side effects and safety:
- Most side effects are mild and temporary, including fever, mild rash, or swelling of lymph nodes.
- Serious side effects are extremely rare, and decades of research confirm that the MMR vaccine is safe and does not cause autism, contrary to misinformation spread in the early 2000s.
- Allergic reactions to the vaccine are rare but can occur, especially in individuals with severe allergies to components like gelatin or neomycin.
Community (herd) immunity:
- Achieving ≥90% vaccine coverage is essential to prevent large outbreaks.
- Unvaccinated individuals, including those too young or with certain medical exemptions, rely on herd immunity for protection.
Public Health Guidelines
Preventing the spread of mumps requires coordinated public health measures, particularly when cases are detected.
Isolation recommendations:
- Individuals with mumps should remain isolated at home for at least 5 days after the onset of parotid gland swelling (the most visible symptom).
- During isolation, close contact should be avoided, particularly with those who are pregnant, immunocompromised, or unvaccinated.
Hygiene measures:
- Wash hands frequently with soap and water for at least 20 seconds.
- Use tissues or the elbow to cover coughs and sneezes, followed by proper disposal of tissues.
- Avoid sharing cups, eating utensils, towels, or bedding with others.
Outbreak control measures:
- Public health authorities may conduct contact tracing to identify and monitor individuals who may have been exposed.
- Vaccination campaigns in schools, universities, or workplaces can rapidly increase immunity and help stop an outbreak.
- In some countries, public health laws allow temporary exclusion of unvaccinated children from schools during outbreaks.
Mumps in Specific Populations
Mumps affects different groups with varying severity and complications. Age and physiological status influence the clinical course and risks associated with the infection.
Mumps in Children
In children, mumps is generally a mild to moderate illness, presenting most often with swelling of the salivary glands—particularly the parotid glands—accompanied by fever, headache, muscle aches, and fatigue. In many cases, the disease resolves naturally within 7 to 14 days without causing lasting harm.
However, children are not entirely free from complications. While less common than in adults, conditions such as orchitis (inflammation of the testicles) can still occur in post-pubertal boys, sometimes resulting in temporary discomfort and swelling. Other possible complications include meningitis, pancreatitis, or hearing loss, though these are rare.
Vaccination coverage plays a decisive role in controlling mumps incidence among children, as unvaccinated or partially vaccinated children are more likely to contract the virus during outbreaks. Supportive treatment in children typically includes ensuring adequate hydration, controlling pain and fever with over-the-counter medications like paracetamol or ibuprofen, and keeping the child isolated from others to reduce the spread of infection.
Mumps in Adults
Adults tend to experience more severe symptoms from mumps than children, and the risk of complications increases significantly with age. In men, mumps frequently causes orchitis, which can be painful and may lead to testicular atrophy (shrinkage) in some cases.
While permanent infertility is rare, the possibility exists, especially when both testicles are affected. In women, oophoritis (inflammation of the ovaries) can occur, causing lower abdominal pain and tenderness, although it does not typically affect fertility.
Adult patients are also at a higher risk of developing serious complications such as aseptic meningitis, encephalitis, pancreatitis, or permanent sensorineural hearing loss. Because symptoms in adults are often more intense and prolonged, recovery can take longer compared to children.
Management remains supportive, with an emphasis on rest, fluid intake, and symptom control. In outbreak situations, public health authorities may recommend a third MMR vaccine dose for adults in high-risk settings to reduce transmission.
Pregnancy and Mumps
Mumps during pregnancy can lead to adverse outcomes, particularly if infection occurs in the first trimester. It is associated with increased risk of spontaneous abortion.
No evidence links mumps to congenital malformations. Treatment prioritizes symptom relief and monitoring fetal health. Pregnant women should avoid exposure, especially if unvaccinated or lacking immunity.
Long-Term Outlook and Recovery
Recovery from mumps varies depending on the severity of the infection and the individual’s overall health. While many recover without lasting issues, some cases may result in complications that require ongoing medical attention.
Prognosis
Most individuals with mumps recover fully within two to three weeks. Symptoms such as swelling and fever usually resolve without intervention beyond supportive care.
Hospitalization is rare and generally only necessary for severe complications. Immunity after infection tends to be lifelong, significantly reducing the risk of reinfection.
Prompt medical attention for symptoms related to complications can improve outcomes. Vaccination remains the most effective prevention measure, lowering both incidence and severity.
Potential Long-Term Effects
Though uncommon, mumps can cause permanent damage. Orchitis affects about 15-30% of post-pubertal males and can lead to testicular atrophy or infertility in rare cases.
Other risks include meningitis, which may cause lasting neurological symptoms, and hearing loss due to inner ear involvement. Pancreatitis and oophoritis might also cause persistent discomfort or dysfunction.
Monitoring for these complications is important, especially in adults and those with severe initial symptoms. Early diagnosis and management can minimize lasting damage.
Global Impact of Mumps
Mumps is a contagious viral infection that affects populations worldwide. It primarily spreads through respiratory droplets, causing outbreaks in communities with low vaccination coverage.
The disease burden varies significantly between countries. In regions with widespread MMR (measles, mumps, rubella) vaccination, mumps cases have declined sharply. However, in areas lacking sufficient immunization, the virus still causes periodic outbreaks.
Affected groups include:
- Children and adolescents
- Young adults, especially in close-contact settings
- Unvaccinated or partially vaccinated individuals
The World Health Organization estimates that mumps causes thousands of cases annually, though exact numbers are difficult to confirm due to underreporting.
Outbreaks can lead to complications such as orchitis, meningitis, and hearing loss. These health issues contribute to the global public health challenge posed by mumps.
Vaccination remains the most effective tool to control the disease. Countries with high vaccination rates typically record fewer severe cases and less transmission.
| Region | Vaccination Coverage | Common Outcome |
| North America | High (>90%) | Rare outbreaks, mild cases |
| Sub-Saharan Africa | Low (<50%) | Frequent outbreaks, higher complications |
| Southeast Asia | Moderate (60-80%) | Occasional outbreaks |
Efforts to increase vaccination coverage globally are critical to reducing the impact of mumps. Public health strategies focus on awareness, vaccine accessibility, and surveillance.