To diagnose a measles or mumps infection; to establish whether a person has immunity to measles or mumps due to a previous infection or to vaccination; to confirm a measles or mumps case and investigate its source
Measles and Mumps Tests
When a person has symptoms or complications that a health practitioner suspects are due to a measles or mumps infection; whenever it is necessary or desired to determine measles or mumps immunity; when an outbreak of measles or mumps is occurring in order to track and minimize it
A blood sample drawn from a vein in your arm for measles or mumps antibody testing; to detect the virus itself, sample may be blood, urine, nasopharyngeal (nasal) aspirate/washing, throat swab, swab of the inside of the cheek (buccal swab), cerebrospinal fluid, or other body tissue
Prior to collection of a buccal swab for mumps, the salivary gland located in front of and below the ear (parotid gland) is massaged. For other specimens, no test preparation is needed.
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How is it used?
Measles and mumps tests may be used to:
- Confirm that a person is immune to the viruses due to previous infections or vaccination
- Diagnose an active case of measles or mumps
- Detect, monitor, and track outbreaks for public health purposes
(See the "What is being tested?" section for more about measles and mumps infections.)
A few different methods are available to test for measles or mumps:
Antibody testing (serology)
Antibody testing may be used to confirm immunity, diagnose an active case, or to track outbreaks. Measles and mumps antibodies are virus-specific proteins produced by the immune system in response to an infection by the measles or mumps virus, or in response to vaccination. There are two types of antibodies produced, IgM and IgG. The first type to appear in the blood after exposure or vaccination is IgM antibodies. Levels of IgM antibodies increase for several days to a maximum level and then begin to taper off over the next few weeks. IgG antibodies take a bit longer to develop, but once they do, they stay positive for life, providing protection against re-infection. Sometimes, testing of two blood samples obtained weeks apart (acute and convalescent) is used to differentiate between an active and prior infection by comparing the level of antibody in the two samples.Direct detection of the virus
Direct detection may involve culturing the virus or molecular methods such as PCR and may be done on a variety of samples. These methods only identify active infections and cannot confirm immunity.Viral genetic testing (RT-PCR) detects and identifies the genetic strain of the virus. Most RT-PCR testing is performed by public health laboratories and the Centers for Disease Control and Prevention (CDC).
Viral detection testing may occasionally be performed to identify the cause of severe complications that may be associated with an infection from the measles or mumps virus. Since people with weakened immune systems may not have a typical antibody response, a viral culture or a test to detect viral genetic material may be performed to confirm the diagnosis of a mumps or measles infection, especially if antibody results do not match clinical findings or a health practitioner's suspicions.
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When is it ordered?
An IgG antibody test for measles or mumps may be ordered whenever a health practitioner wants to determine whether a person is immune to one or both of the viruses, either because of a previous infection or due to vaccination.
Measles or mumps IgM and IgG antibody tests, viral culture, or PCR may be ordered when a person has characteristic signs and symptoms of measles or mups or has had exposure to someone with the virus and now has a fever and some symptoms that could be due to measles or mumps. These tests are typically ordered early in the course of the infection.
Signs and symptoms of measles develop 7-18 days after exposure and usually include one or more of the following:
- A characteristic rash that usually starts on the face and spreads down the body to the trunk and legs
- High fever
- Dry cough
- Red, watery, itchy eyes
- Sensitivity to light
- A runny nose
- Sore throat
- Tiny white spots inside the mouth
Signs and symptoms of mumps typically develop after a 2 to 3 week incubation period and often resemble symptoms of the flu, such as:
- Headache
- Muscle aches
- Fever
- These are followed by characteristic swelling of the salivary glands below one or both ears called parotitis.
Testing may also be ordered during a suspected or confirmed outbreak, when several people may have been exposed and have the signs and symptoms listed above.
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What does the test result mean?
Antibody testing
When measles or mumps IgM antibodies are present in someone who has not been recently vaccinated, then it is likely that the person has a current measles or mumps infection. When both IgM and IgG antibodies are present or there is a fourfold increase in concentrations between acute and convalescent IgG antibody tests, then it is likely that the person has a current or had a recent measles or mumps infection.When measles or mumps IgG antibodies are present in a person who has been vaccinated and/or is not currently ill, then that person is protected against infection (immune). If a person does not have measles or mumps IgG antibodies, then that person is not considered immune to the viruses. This may be because the person has not been exposed to the viruses, because the IgG has not had time to be produced, or because the person does not have a normal antibody response.
The following table summarizes results that may be seen with antibody testing:
IgM IgG Possible Interpretation(s) Positive Negative Early infection Positive Positive (with increase in levels between acute and convalescent samples; this would only be done if the IgM test is not available) Current or recent infection Negative Positive Immunity from prior infection or vaccination Negative Negative No current or prior infection; not immune; no or low immune response due to compromised immune system Viral isolation (detection)
A positive measles culture or mumps culture or a positive PCR test for the virus's genetic material means that the person has a current viral infection.If a specific strain of measles or mumps virus is identified, then this genetic strain is the cause of the infection and the genetic information can be used to help determine the source of a measles or mumps infection, such as recent travel to a specific country or recent exposure to another person with an active infection. The result of measles or mumps genetic testing is used by the Centers for Disease Control and Prevention (CDC) to monitor the spread of the virus, to identify outbreaks, and prevent further transmission.
If the measles or mumps culture or PCR is negative, it may mean that the person is not infected and signs and symptoms are due to another cause. However, a negative result does not necessarily rule out an active infection because the virus may have been present in numbers too low to detect or may not have been present in the sample tested. If an infection is strongly suspected after a negative result, repeat or follow-up testing may be done.
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Is there anything else I should know?
Most people recover from measles within a couple of weeks, but up to 20% develop complications that may include an ear infection, bronchitis, pneumonia, diarrhea, or more rarely encephalitis or blindness.
Mumps is most often a mild self-limited illness, but some people may develop complications such as deafness, inflammation of the testicles (orchitis) or ovaries (oophoritis), pancreatitis, meningitis, or encephalitis.
The measles, mumps, rubella (MMR) vaccine contains a live, attenuated (weakened) form of the viruses. Those with weakened immune systems and those who are pregnant or planning to become pregnant within the next month should not receive the vaccine. The initial dose of the vaccine is recommended for infants at 12-15 months of age and a second dose is given at 4-6 years of age.
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If I have measles or mumps and develop complications, will they go away once the infection resolves?In most cases they will, but some complications, such as blindness, deafness, and rarely tissue or organ damage, may be permanent. The swelling of testicles (orchitis) that is sometimes seen with mumps can occasionally cause sterility.
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When do people typically get measles and mumps vaccinations?
Two doses of the MMR vaccine are needed for full protection. Children are given the first dose of MMR vaccine between 12 and 15 months of age and a booster immunization is typically given before the start of kindergarten between 4 and 6 years of age.
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Should everyone be tested for measles and mumps immunity?
A test to document antibody response to the MMR vaccine is not recommended since most people mount an antibody response to the viruses in the vaccine. There are several common situations, such as entry to a university or employment in a health care setting, where you may need to provide proof that you have had the measles and mumps infections, or that you have had two MMR vaccinations, or that you have immunity to measles and mumps infection.