Mumps

A contagious viral infection primarily affecting the parotid salivary glands

Table of Contents

Overview

Mumps is a highly contagious viral infection that primarily affects the parotid glands, which are the major salivary glands located on either side of the face, just below and in front of the ears. Once a common childhood illness, mumps has become relatively rare in developed countries due to widespread vaccination with the measles, mumps, and rubella (MMR) vaccine. However, outbreaks still occur, particularly in close-contact settings such as schools, colleges, and communities with low vaccination rates.

The disease is caused by the mumps virus, a member of the paramyxovirus family. While mumps is generally considered a mild illness in children, it can lead to serious complications, especially in adolescents and adults. These complications can include orchitis (inflammation of the testicles) in males, oophoritis (inflammation of the ovaries) in females, pancreatitis, encephalitis, and hearing loss. Understanding the nature of mumps, its transmission, and the importance of vaccination is crucial for preventing outbreaks and protecting vulnerable populations.

The incubation period for mumps is typically 16-18 days, but can range from 12-25 days after exposure. During this time, infected individuals may be contagious before symptoms appear, making it challenging to prevent transmission. The characteristic swelling of the parotid glands usually develops 2-3 weeks after infection and gives the patient a distinctive "chipmunk-like" appearance.

Symptoms

Mumps symptoms typically begin with a few days of nonspecific symptoms before the characteristic parotid gland swelling appears. About 20-30% of mumps infections are asymptomatic, particularly in young children.

Early Symptoms (Prodromal Phase)

Characteristic Symptoms

  • Swollen salivary glands - Usually bilateral parotid swelling, giving a "chipmunk" appearance
  • Ear pain (otalgia) - Due to proximity of swollen glands to the ears
  • Pain when chewing or swallowing, especially acidic foods
  • Tenderness of the swollen glands
  • Difficulty opening the mouth (trismus)
  • Dry mouth - Due to decreased saliva production

Complications and Associated Symptoms

In Males

  • Testicular pain and swelling (orchitis) - Occurs in 15-30% of post-pubertal males
  • Abdominal pain
  • Nausea and vomiting

In Females

  • Lower abdominal pain (oophoritis) - Less common than orchitis
  • Pelvic discomfort

Neurological Symptoms

  • Severe headache
  • Neck stiffness (meningitis)
  • Confusion or altered mental status
  • Seizures (rare)

Other Complications

  • Upper abdominal pain (pancreatitis)
  • Hearing loss (usually unilateral)
  • Joint pain and swelling

Causes

Mumps is caused by the mumps virus, a single-stranded RNA virus belonging to the genus Rubulavirus in the Paramyxoviridae family. Understanding how the virus spreads and infects individuals is crucial for prevention and control measures.

The Mumps Virus

  • Single serotype with minor genetic variations
  • Relatively stable virus with low mutation rate
  • Humans are the only natural host
  • Survives poorly outside the human body

Transmission

Mumps spreads through several routes:

Respiratory Droplets

  • Primary mode of transmission
  • Spread through coughing, sneezing, or talking
  • Can travel up to 3 feet from infected person
  • Virus can remain airborne briefly

Direct Contact

  • Contact with infected saliva
  • Sharing utensils, cups, or food
  • Kissing or close personal contact

Fomites

  • Contaminated surfaces and objects
  • Virus can survive on surfaces for hours
  • Less common mode of transmission

Contagious Period

  • Most contagious 1-2 days before parotid swelling
  • Remains contagious up to 5 days after swelling onset
  • Asymptomatic individuals can still transmit the virus
  • Viral shedding begins before symptoms appear

Risk Factors

Several factors increase the risk of contracting mumps or experiencing complications from the infection.

Vaccination Status

  • Unvaccinated individuals - Highest risk group
  • Incomplete vaccination - Those who received only one dose of MMR
  • Waning immunity - Protection may decrease over time
  • Vaccine failure - About 88% effective after two doses

Age Factors

  • School-age children - If unvaccinated
  • Adolescents and young adults - Higher risk of complications
  • Adults over 50 - May lack natural immunity if not previously exposed

Environmental Factors

  • Crowded living conditions - Dormitories, military barracks
  • Educational institutions - Schools, colleges, daycare centers
  • International travel - To areas with low vaccination rates
  • Close-contact settings - Sports teams, social gatherings

Immunocompromised States

  • HIV/AIDS
  • Cancer treatment recipients
  • Organ transplant recipients
  • Those on immunosuppressive medications

Seasonal Patterns

  • Peak incidence in late winter and spring
  • Outbreaks more common in closed environments during colder months

Diagnosis

Diagnosing mumps typically involves clinical evaluation combined with laboratory testing, especially in cases where the presentation is atypical or during outbreak investigations.

Clinical Diagnosis

The diagnosis is often made based on characteristic clinical features:

  • Bilateral parotid gland swelling
  • Prodromal symptoms followed by glandular swelling
  • Known exposure to mumps
  • Lack of vaccination history

Physical Examination

Key Findings

  • Parotid gland enlargement and tenderness
  • Obscured angle of the jaw
  • Earlobe pushed upward and outward
  • Redness at opening of Stensen's duct
  • Difficulty palpating the angle of mandible

Laboratory Testing

RT-PCR (Reverse Transcription Polymerase Chain Reaction)

  • Most sensitive test for acute infection
  • Can detect virus in saliva, urine, or CSF
  • Best performed within 3-10 days of symptom onset
  • Preferred method for confirming diagnosis

Serology

  • IgM antibodies - Indicate recent infection
  • IgG antibodies - Show past infection or vaccination
  • Four-fold rise in IgG titer confirms acute infection
  • May be negative early in infection

Viral Culture

  • Less commonly used due to technical difficulty
  • Lower sensitivity than RT-PCR
  • Takes several days for results

Differential Diagnosis

Conditions that may mimic mumps include:

  • Bacterial parotitis
  • Salivary gland stones
  • Epstein-Barr virus infection
  • Cytomegalovirus infection
  • HIV-associated parotid enlargement
  • Salivary gland tumors
  • Drug-induced parotid swelling

Treatment Options

There is no specific antiviral treatment for mumps. Management focuses on supportive care to relieve symptoms and prevent complications. Most people recover completely within two weeks.

Supportive Care

Pain and Fever Management

  • Acetaminophen (Tylenol) - For fever and pain relief
  • Ibuprofen (Advil, Motrin) - Anti-inflammatory effect may help with swelling
  • Avoid aspirin in children due to risk of Reye's syndrome
  • Apply warm or cold compresses to swollen glands

General Measures

  • Rest - Bed rest during acute phase
  • Hydration - Plenty of fluids to prevent dehydration
  • Soft diet - Avoid foods requiring excessive chewing
  • Avoid acidic foods - Citrus fruits and juices may increase pain
  • Good oral hygiene - Gentle mouth care to prevent secondary infections

Management of Complications

Orchitis

  • Bed rest with scrotal support
  • Ice packs to reduce swelling
  • Anti-inflammatory medications
  • Stronger pain medications if needed
  • Hospitalization for severe cases

Meningitis/Encephalitis

  • Hospitalization for monitoring
  • Intravenous fluids
  • Anti-inflammatory medications
  • Supportive neurological care

Pancreatitis

  • NPO (nothing by mouth) initially
  • Intravenous hydration
  • Pain management
  • Gradual reintroduction of oral intake

Isolation Measures

  • Isolate for 5 days after onset of parotid swelling
  • Avoid contact with susceptible individuals
  • Stay home from work, school, or daycare
  • Practice good respiratory hygiene
  • Frequent handwashing

Follow-up Care

  • Monitor for development of complications
  • Hearing assessment if concern for hearing loss
  • Fertility evaluation for males who experienced bilateral orchitis
  • Report case to public health authorities

Prevention

Vaccination is the most effective way to prevent mumps. The MMR vaccine has dramatically reduced the incidence of mumps in countries with high vaccination coverage.

MMR Vaccination

Vaccination Schedule

  • First dose: 12-15 months of age
  • Second dose: 4-6 years of age
  • Catch-up vaccination: For unvaccinated adolescents and adults
  • Third dose: May be recommended during outbreaks

Vaccine Effectiveness

  • One dose: Approximately 78% effective
  • Two doses: Approximately 88% effective
  • Immunity may wane over time
  • Breakthrough infections can occur but are usually milder

Special Populations

Healthcare Workers

  • Should have documented immunity
  • Two doses of MMR vaccine recommended
  • Serologic testing may be performed

International Travelers

  • Ensure up-to-date vaccination status
  • Consider additional dose if traveling to endemic areas
  • Infants 6-11 months may receive early dose

Contraindications to Vaccination

  • Pregnancy (live vaccine)
  • Severe immunodeficiency
  • Recent blood transfusion
  • Severe allergic reaction to vaccine components
  • Active tuberculosis

Post-Exposure Prophylaxis

  • MMR vaccine within 72 hours of exposure may provide some protection
  • Not effective if given after symptom onset
  • Immune globulin is not effective for mumps
  • Monitor exposed individuals for 25 days

Community Prevention Measures

  • Maintain high vaccination coverage (>90%)
  • Prompt identification and isolation of cases
  • Contact tracing during outbreaks
  • Education about vaccine importance
  • Address vaccine hesitancy

When to See a Doctor

While mumps often resolves without complications, certain symptoms warrant immediate medical attention.

Seek Immediate Medical Care If:

  • Severe headache with neck stiffness (possible meningitis)
  • Confusion, drowsiness, or difficulty staying awake
  • Seizures
  • Severe abdominal pain (possible pancreatitis)
  • Testicular pain and swelling in males
  • Persistent vomiting
  • High fever over 103°F (39.4°C)
  • Difficulty breathing

Schedule an Appointment If:

  • Suspected mumps exposure in unvaccinated individual
  • Parotid gland swelling lasting more than 10 days
  • Hearing problems developing after mumps
  • Persistent fever beyond one week
  • Concerns about fertility after orchitis
  • Need for vaccination status verification

Public Health Considerations

  • Mumps is a reportable disease in most jurisdictions
  • Healthcare providers must notify public health authorities
  • Contact tracing may be initiated
  • Exclusion from school/work may be required

Frequently Asked Questions

Can you get mumps more than once?

It's very rare to get mumps more than once. Natural infection usually provides lifelong immunity. However, some cases of reinfection have been reported, particularly in individuals with compromised immune systems. If someone who has had mumps develops similar symptoms again, it's more likely to be a different condition affecting the salivary glands.

Can vaccinated people still get mumps?

Yes, vaccinated individuals can still contract mumps, though it's much less likely. The MMR vaccine is about 88% effective after two doses, meaning about 12 out of 100 vaccinated people may still get mumps if exposed. However, vaccinated individuals who do get mumps typically have milder symptoms and fewer complications.

Does mumps cause infertility?

While mumps orchitis (testicular inflammation) can occur in 15-30% of post-pubertal males with mumps, permanent infertility is rare. Orchitis usually affects one testicle, and even when both are affected, most men retain normal fertility. However, in rare cases, bilateral orchitis can lead to reduced sperm production or infertility.

How long is someone with mumps contagious?

A person with mumps is most contagious from 2 days before to 5 days after the onset of parotid gland swelling. However, they may be contagious for up to 7 days before and 9 days after swelling appears. This is why isolation for at least 5 days after swelling begins is recommended.

Is the MMR vaccine safe?

Yes, the MMR vaccine is very safe and has been used for decades. Serious side effects are extremely rare. Common mild side effects may include soreness at the injection site, mild fever, or a faint rash. The vaccine does not cause autism - this has been thoroughly disproven by numerous large-scale studies.

References

  1. Centers for Disease Control and Prevention. Mumps. Updated 2023.
  2. Hviid A, et al. Mumps. Lancet. 2008;371(9616):932-44.
  3. Rubin S, et al. Molecular biology, pathogenesis and pathology of mumps virus. J Pathol. 2015;235(2):242-52.
  4. World Health Organization. Mumps virus vaccines: WHO position paper. Weekly Epidemiological Record. 2007;82(7):51-60.
  5. American Academy of Pediatrics. Mumps. In: Red Book: 2021-2024 Report of the Committee on Infectious Diseases. 32nd ed.
  6. Kutty PK, et al. Guidance for isolation precautions for mumps in the United States: a review of the scientific basis for policy change. Clin Infect Dis. 2010;50(12):1619-28.