Mumps Virus Antibody, IgG, Serum
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
The mumps virus is a member of the Paramyxoviridae family of viruses, which include parainfluenza virus serotypes 1-4, measles, respiratory syncytial virus (RSV), and metapneumovirus. Mumps is highly infectious among unvaccinated individuals and is typically transmitted through inhalation of infected respiratory droplets or secretions. Following an approximately 2 week incubation period, symptom onset is typically acute with a prodrome of low-grade fever, headache, and malaise.(1,2) Painful enlargement of the salivary glands, the hallmark of mumps, occurs in approximately 60% to 70% of infections and in 95% of patients with symptoms. Testicular pain (orchitis) occurs in approximately 15% to 30% of postpubertal men and abdominal pain (oophoritis) is found in 5% of postpubertal women.(1) Other complications include mumps-associated pancreatitis (<5% of cases) and central nervous system disease (meningitis <10% and encephalitis <1%).
Widespread routine immunization of infants with attenuated mumps virus has dramatically decreased the number of reported mumps cases in the United States. However, outbreaks continue to occur, indicating persistence of the virus in the general population.
Laboratory diagnosis of mumps is typically accomplished by detection of IgM- and IgG-class antibodies to the mumps virus. However, due to the widespread mumps vaccination program, in clinically suspected cases of acute mumps infection, serologic testing should be supplemented with virus isolation in culture or detection of viral nucleic acid by PCR in throat, saliva, or urine specimens.
Determination of postimmunization immune response of individuals to the mumps vaccine
Documentation of previous infection with mumps virus in an individual with no previous record of immunization to mumps virus
Positive: The presence of detectable IgG-class antibodies indicates prior exposure to the mumps virus through infection or immunization. Individuals testing positive are considered immune to mumps virus.
Equivocal: Submit an additional specimen for testing in 10 to 14 days to demonstrate IgG seroconversion if recently vaccinated or if otherwise clinically indicated.
Negative: The absence of detectable IgG-class antibodies suggests no prior exposure to the mumps virus or the lack of a specific immune response to immunization.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Mumps virus shares antigenic relationships with other viruses of the paramyxovirus group; therefore serologic cross-reactions are possible, but uncommon with this test procedure.(2)
IgG-class antibodies to mumps virus may be present in serum specimens from individuals who have received blood products within the past several months, but have not been immunized or experienced past infection with this virus.
Serum samples drawn early during acute phase of infection may be negative for IgG-class antibodies to this virus.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Vaccinated: Positive (> or =1.1 AI)
Unvaccinated: Negative (< or =0.8 AI)
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Hviid A, Rubin S, Muhlemann K: Mumps. Lancet 2008 Mar;371(9616):932-944
2. Hodinka RL, Moshal KL: Childhood infections. In Essentials of Diagnostic Virology. Edited by GA Storch. Churchill Livingstone, New York, 2000, pp 168-178