Measles Antibodies (IgG, IgM), Diagnostic

34166

1 mL serum

0.5 mL

Plastic screw-cap vial

Room temperature

Room temperature: 4 days
Refrigerated: 7 days
Frozen: 30 days

Set up: Tues-Sat; Report available: Next day

Measles Antibody (IgG)

AU/mL	Interpretation
<13.50	Negative
13.50-16.49	Equivocal
>16.49	Positive

The presence of measles IgG suggests immunization or past or current infection with measles virus.

Measles Antibody (IgM)

Titer	Interpretation
<1:20	Antibody not detected
≥1:20	Antibody detected

The traditional serologic diagnosis of measles requires a significant rise in antibody titer between acute and convalescent sera. However, detection of IgM antibody in a single specimen may indicate acute disease.
Correct interpretation of serologic data depends upon the proper timing of specimen collection in relation to rash onset. This timing is particularly important for interpreting negative IgM results, since IgM antibody peaks approximately 10 days after rash onset and is usually undetectable 30 days after rash onset.

Measles, also known as Rubeola, causes fever, irritability, respiratory illness, and the characteristic skin rash. Immunization has greatly diminished the incidence of measles. The presence of IgG is consistent with immunity or prior exposure. IgM is consistent with current or recent infection. IgM tests can generate false positive results and low levels of IgM can persist for longer than 12 months.