What is the purpose of this test?
Order this Rubella Antibodies Blood Test, IgG, to detect antibodies to rubella and confirm previous infection or vaccination. Rubella is a viral infection that typically begins with a skin rash and fever. Although rubella has been eliminated from the United States due to widespread immunization with the measles-mumps-rubella (MMR) vaccine, it can be spread by unvaccinated people who contract the virus abroad before returning to the United States.
Although rubella is usually a mild illness that goes away without treatment, it can have severe effects if transmitted to unvaccinated individuals or a developing fetus during pregnancy. As a result, often schools and certain companies require their students and workers to provide proof of immune status. In addition, healthcare providers may order this test as part of prenatal screening.
What is the difference between rubella IgG and IgM antibody tests?
IgM antibody testing is typically the first test used to diagnose rubella. Individuals who are newly infected with rubella develop IgM antibodies to the virus. Most individuals will develop IgM antibodies as soon as four days after the onset of symptoms. However, IgM antibody levels can remain detectable for six to eight weeks after infection.
IgG antibody testing is another antibody test that may be used to diagnose rubella and establish immunity. In addition, IgG testing is also the preferred method for checking immunity to rubella in pregnant women.
When should I order a Rubella Antibodies Blood Test, IgG?
Individuals interested in determining their immunity to rubella may order this test. Individuals should also note that this test cannot distinguish between a past or current infection; therefore, a positive result may indicate active infection and not immunity. However, suppose an active infection is not suspected based on the individual’s history, clinical signs, and other laboratory results. In that case, a positive IgG result is likely due to past infection, and the individual is assumed to be immune to the disease. Individuals are advised to follow up with their doctor or healthcare provider if they have significant concerns or questions about their results.
Common signs or symptoms of a rubella infection may include:
- Fever
- Headaches
- Skin rash
- Sore throat
- Joint pain or stiffness
- Conjunctivitis (pink eye)
