rubella blood test detects
antibodies that are made by the
immune system to help kill the
rubella virus. These antibodies remain in the
bloodstream for years. The presence of certain antibodies means a recent
infection, a past infection, or that you have been vaccinated against the
Rubella (also called German measles or 3-day measles)
usually does not cause long-term problems. But a woman infected with the
rubella virus during pregnancy can transmit the disease to her baby (fetus). And serious birth defects called congenital
rubella syndrome (CRS) could develop, especially during the first
trimester. Birth defects of CRS include cataracts and
other eye problems, hearing impairment, and heart disease.
Miscarriage and stillbirth are also possible
consequences for pregnant women. The vaccination to prevent rubella protects
against these complications.
A rubella test is usually done for a
woman who is or wants to become pregnant to determine whether she is at risk
for rubella. Several laboratory methods can be used to detect rubella
antibodies in the blood. The most commonly used method is the enzyme-linked
immunosorbent assay (ELISA, EIA).
Why It Is Done
A test for
rubella is done to find out if:
- A woman who is or wants to become pregnant is
immune to rubella.
- A recent infection was caused by the rubella
virus. The presence of IgM antibodies means a current or recent
- A person has been vaccinated against rubella. The
presence of IgG antibodies means immunity received through either
vaccination or a past infection.
- Health professionals who are in
contact with pregnant women have had rubella. A health professional who has not
had rubella may need to be vaccinated to prevent the risk of spreading rubella
to a pregnant woman.
Some babies born with birth defects may be tested for
How To Prepare
No special preparation is required
before having this test.
How It Is Done
The health professional taking a sample
of your blood will:
- Wrap an elastic band around your upper arm to
stop the flow of blood. This makes the veins below the band larger so it is
easier to put a needle into the vein.
- Clean the needle site with
- Put the needle into the vein. More than one needle stick
may be needed.
- Attach a tube to the needle to fill it with
- Remove the band from your arm when enough blood is
- Put a gauze pad or cotton ball over the needle site as
the needle is removed.
- Put pressure on the site and then put on a
How It Feels
The blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or