Preeta K. Kutty, Albert E. Barskey IV, Kathleen M. Gallagher

Infectious Agent

• Mumps virus is an enveloped, negative-strand RNA virus, a member of the genus Rubulavirus.
• Humans are the only known natural host for mumps virus.

Mode of Transmission

• Transmission is by respiratory droplets, saliva, or contact with contaminated fomites.
• Patients are usually contagious 1–2 days (occasionally as long as 7 days) before symptom onset until 5 days afterward.

Occurrence

• With the exception of the multistate outbreak in 2006, mumps is an uncommon disease in the United States because of a successful vaccination program.
• Mumps virus remains endemic in many countries throughout the world because mumps vaccine is used in only 57% of the World Health Organization member countries.

Risk for Travelers

• The risk of exposure to mumps among travelers can be high in most countries of the world, especially for travelers >12 months of age who do not have evidence of mumps immunity (see Preventive Measures for Travelers later in this section). Although some countries have had variable successes with a national vaccination program—including Finland, which has declared elimination—the risk of contacting imported mumps in these countries is still a concern.
• Acceptable presumptive evidence of immunity to mumps for international travelers includes—
  • Documented administration of two doses of live mumps virus vaccine at least 28 days apart, on or after the first birthday
  • Laboratory evidence of immunity
  • Birth before 1957
  • Documentation of physician-diagnosed mumps

Clinical Presentation

• Incubation period from exposure to onset of symptoms is generally 16–18 days (range 12–25 days).
• Onset of illness is usually nonspecific, with symptoms of fever, headache, malaise, myalgia, and anorexia.
• Mumps is characterized by parotitis, either unilateral or bilateral.
• Although mumps is generally a mild and self-limited disease, complications of mumps infection can include deafness; orchitis, oophoritis, or mastitis (inflammation of the testicles, ovaries or breasts, respectively); pancreatitis; and meningitis or encephalitis. With the exception of deafness, these complications are more frequent in adults than in children.

Diagnosis

• Mumps may occur in epidemics; mumps virus is the only cause of epidemic parotitis.
• Diagnosis is usually clinical, based on the presence of parotitis and associated signs, symptoms, or complications.
• Clinical case definition: An illness with acute onset of unilateral or bilateral tender, self-limited swelling of the parotid glands, other salivary gland(s), or both, lasting at least 2 days, and without other apparent cause.
• Laboratory criteria include—
  • Isolation of mumps virus from clinical specimen
  • Detection of mumps nucleic acid (e.g., standard or real-time RT-PCR assays)
  • Detection of mumps IgM antibody
  • Demonstration of specific mumps antibody response in the absence of recent vaccination, either a fourfold increase in IgG titer as measured by quantitative assays, or seroconversion from negative to positive by using a standard serologic assay of paired acute- and convalescent-phase serum specimens
• Laboratory specimens that can be collected are serum for serology (IgM, IgG) and a buccal swab (or a throat swab) for viral specimens. For more information see www.cdc.gov/vaccines/vpd-vac/mumps/outbreak/faqs-lab-spec-collect.htm.
• Laboratory confirmation is more challenging in highly vaccinated populations. Serologic tests should be interpreted with caution. A negative laboratory test should not rule out a clinically compatible case, especially in a two-dose vaccine recipient.

Treatment

There is no specific antiviral therapy for mumps, and the basic treatment consists of supportive care.

Preventive Measures for Travelers

Vaccine

• Although vaccination against mumps is not a requirement for entry into any country (including the United States), travelers leaving the United States or living abroad should ensure they are immune to mumps.
• Mumps vaccine contains live, attenuated mumps virus. It is available as a monovalent formulation and in combination formulations, such as MMR. Combined MMR vaccine is recommended whenever one or more of the individual components is indicated to provide optimal protection against measles and rubella. Mumps vaccine is highly, but not 100%, effective in preventing mumps. One dose of mumps vaccine is approximately 80%–85% effective in preventing clinical mumps with parotitis, and two doses are approximately 90% effective.
• Mumps vaccine has not been demonstrated to be effective in preventing infection after exposure; however, it can be administered postexposure to provide protection against subsequent exposures. Immune globulin is not effective in preventing mumps infection following an exposure and is not recommended.

Adverse Reactions, Precautions, and Contraindications to Mumps Vaccine

• Refer to theMeasles (Rubeola) section earlier in this chapter for information on reactions following MMR vaccine and additional precautions and contraindications.

General Vaccine Recommendations, Pediatric and Catch-Up Schedules, and Recommendations for Special Populations

• Refer to Chapters 7 and 8.

References

1. American Academy of Pediatrics. Mumps. In: Pickering LK, Baker CJ, Long SS, McMillan JA, editors. Red book: 2006 report of the Committee on Infectious Diseases. 27th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2003. p. 464–8.
2. CDC. Updated recommendations for isolation of persons with mumps. MMWR Morbid Mortal Wkly Rep. 2008;57(40):1103–5.
3. World Health Organization. Global status of mumps immunization and surveillance. Wkly Epidemiol Rec. 2005;80(48):417–24.
4. CDC. Measles, mumps, and rubella-vaccine use and strategies for elimination of measles, rubella, and congenital rubella syndrome and control of mumps. Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Morbid Mortal Wkly Rep. 1998;47(RR-8):1–57.
5. CDC. Notice to readers: Updated recommendations of the Advisory Committee on Immunization Practices (ACIP) for the control and elimination of mumps. MMWR Morbid Mortal Wkly Rep. 2006;55(22):629–30.
6. CDC. Measles prevention: recommendations of the Immunization Practices Advisory Committee on Infectious Diseases (ACIP). MMWR Morbid Mortal Wkly Rep. 1989;38(No. S-9):1–18.
7. Plotkin SA, Rubin S. Mumps Vaccine. In: Plotkin SA, Orenstein WA, Offit PA, editors. Vaccines. 5th ed. Philadelphia: Elsevier Saunders; 2008. p. 436–65.
8. Watson JC, Hadler SC, Dykewicz CA, et al.; CDC. Measles, mumps and rubella vaccine use and strategies for elimination of measles, rubella, and congenital rubella syndrome and control of mumps: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Morbid Mortal Wkly Rep. 1998;47(RR-8):1–57.
9. Council of State and Territorial Epidemiologists. Infectious Disease Committee. Revision of the surveillance case definition for mumps. [cited 2008 Nov 25] Available from:http://www.cste.org/PS/2007ps/2007psfinal/ID/07-ID-02.pdf (PDF).
10. Harling R, White JM, Ramsay ME, et al. The effectiveness of the mumps component of the MMR vaccine: a case control study. Vaccine. 2005;23(31):4070–4.