What does rubella virus IgG positive mean?

The rubella test is ordered when a woman is pregnant or is planning on becoming pregnant. It is ordered whenever a check for against rubella is required. and IgG rubella tests may be ordered when a pregnant woman has and that may indicate a rubella infection.

Some signs and symptoms include:

• Mild fever
• A pink rash that begins on the face and then spreads downward to the body and then the legs and arms; once it begins to spread to the body, the rash may disappear from the face.
• Runny or stuffy nose
• Red or inflamed eyes
• Aching
• Swollen lymph nodes

Since many conditions can cause similar symptoms, a health practitioner will need to order the tests in order to confirm the diagnosis.

IgM and IgG tests may be ordered for a newborn when the mother was diagnosed with a rubella infection during pregnancy and/or when a newborn is born with birth defects such as hearing loss, heart defects, or cloudy lens of the eyes (cataracts) that could be due to congenital rubella syndrome (CRS).

Since rubella antibodies take some time to appear after infection, the tests may be repeated after day 5 of illness onset (IgM) and 7-21 days after the first specimen (IgG) to see if the antibody levels have become detectable (when initially absent) and to determine whether the levels are rising or falling over time.

This test may be required of a healthcare worker or a person starting college and is still ordered for women in some states as part of the blood testing required to obtain a marriage license.

What does the test result mean?

Adult or Child

The presence of IgG antibodies but not antibodies indicates a history of past exposure to the virus or vaccination and indicates that the person tested should be immune to the rubella virus.

The presence of IgM antibodies, with or without IgG antibodies, in a child or adult indicates a recent infection with the rubella virus.

Newborn

The presence of IgG antibodies, but not IgM antibodies, in a newborn means that the mother's IgG antibodies have passed to the baby in utero and these antibodies may protect the infant from rubella infection, although they should decrease by four- to eight-fold by three months of age and should disappear by 6 to 12 months of age.