Mumps Virus

Mumps is an acute, contagious disease of short duration, usually self-limiting, and characterized by swelling of the parotid gland. It has become rare in the U.S. due to vaccination programs. Diagnosis is usually clinical and not based on laboratory testing. Serology samples can be collected as soon as diagnosis is suspected. IgM antibody response normally appears 1-2 weeks after disease onset.

Diagnosis

Indications for Testing

  • Atypical presentation of secondary complications in patients with apparent mumps
  • Suspected outbreak – test patients for epidemiologic evidence

Laboratory Testing

  • Limited role for laboratory testing – usually a clinical diagnosis
  • Mumps case definition (CDC, 2012)
  • Mumps information for healthcare providers (CDC, 2016)
  • CDC mumps laboratory testing recommendations (CDC, 2017)
    • CDC recommends buccal or oral swab and blood specimens be collected for all suspected mumps cases
    • Serology
      • Collect initial sample as soon as diagnosis is suspected; collect second sample 5-10 days after symptom onset if initial sample is negative – IgM response may not be detectable until 5 days after onset
      • IgM antibody response normally appears 7-14 days after disease onset
      • IgM antibody response may be delayed or absent in previously vaccinated patients and the period of viral excretion may be shorter
      • IgG assays associated with cross-reactions
      • IgG antibody levels induced by vaccine are lower than those from natural infection
      • Laboratory confirmation of mumps serology (CDC, 2017)
    • Polymerase chain reaction (PCR) – buccal swab
      • Negative test does not rule out mumps – vaccinated individuals typically shed virus in smaller amounts for shorter time
      • Best if collected in first 3 days of illness – greater sensitivity
      • May show positivity during first or recurrent (contralateral) parotitis episode
    • Culture
      • Gold standard
      • Buccal and oral swab specimens preferred
      • Culture growth often necessary for viral sequencing
      • Allows for genotyping, which may be useful in outbreaks
      • Limitation – may take days to weeks to complete

Differential Diagnosis

Background

Epidemiology

  • Prevalence – between 229 (2012) and 6,366 (2016) reported cases in U.S. annually (CDC, 2017)
  • Age – highest incidence, 16-24 years, often due to close-contact settings (school, college dormitories)
  • Transmission – highly contagious and transmitted by droplets spread from the upper respiratory tract

Organism

  • Paramyxoviridae family; Rubulavirus genus
  • Single-stranded RNA virus
  • 12 genotypes based on sequence of SH gene coding for short hydrophobic protein
  • Immunity after infection appears to be lifelong
  • 88% immunity after two-dose immunization (CDC, 2017)

Clinical Presentation

  • Incubation period – 12-25 days (average, 16-18 days) (CDC, 2017)  
  • 25-30% of all infections are silent
  • Most common clinical feature is bilateral or unilateral parotitis
  • Secondary complications

ARUP Lab Tests

Aid in the diagnosis of suspected mumps infection

If equivocal, repeat testing in 10-14 days may be helpful

Not recommended as a stand-alone test unless testing for evidence of antibody production from vaccination 

If equivocal, repeat testing in 10-14 days may be helpful

Detect mumps virus in buccal swab specimens

Culture test for detecting mumps virus in specimens other than cerebrospinal fluid (CSF)

Collect during first 3 days of illness; if collecting urine, collect first morning void

Related Tests

Not recommended

AlertThis test has been temporarily inactivated. In compliance with guidance issued by government agencies, respiratory viral cultures are being temporarily discontinued for the safety of laboratory staff during the COVID-19 pandemic. PCR testing is available for a variety of specific viruses; refer to the Laboratory Test Directory.

Detect common respiratory viruses; molecular methods may offer improved sensitivity

Respiratory viruses rapid culture offers faster turnaround time

Viruses that can be isolated: adenovirus; cytomegalovirus; enterovirus; herpes simplex virus; influenza A and B; parainfluenza types 1, 2, and 3; respiratory syncytial virus; and varicella-zoster virus

Virus-specific tests are recommended

Medical Experts

Contributor

Couturier

Marc Roger Couturier, PhD, D(ABMM)
Associate Professor of Clinical Pathology, University of Utah
Medical Director, Parasitology/Fecal Testing, Infectious Disease Antigen Testing, Bacteriology, and Molecular Amplified Detection, ARUP Laboratories
Contributor
Contributor

References

Additional Resources
  • 18342688

    Hviid A
    Rubin S
    Mühlemann K
    Lancet
    2008
    371
    9616
    932-44
    PubMed
  • Resources from the ARUP Institute for Clinical and Experimental Pathology®