Rubella

Does this test have other names?

German measles, rubella antibody test, 3-day measles

What is this test?

This test measures the amount of rubella antibodies in your blood to see if you have immunity against the rubella virus.

Rubella is also called the German measles. It is a very contagious disease that's easily spread through coughing, sneezing, and spitting. In young children, rubella is usually a mild disease with symptoms that include sore throat and fever. Adults may have pink eye, headache, and discomfort up to 5 days before a rash appears.

It's important to know whether you have antibodies against rubella. This is especially true if you're pregnant or know that you have been exposed to the virus. Getting rubella when you're pregnant can be especially dangerous for your fetus. A rubella infection can cause miscarriage or a stillborn infant in the first 28 weeks of pregnancy. It can also cause many serious birth defects. These are more likely if the infection happens in the first 12 weeks of pregnancy. Defects include heart defects, intellectual disability, liver problems, deafness, blood disorders, and cataracts. Infants may later have delayed motor skills, behavioral disorders, autism, immune disorders, thyroid problems, diabetes, and digestive disorders.

Once you've had rubella, you may get a natural immunity so you won't get it again. If you're not immune or never had rubella, you can get vaccinated.

Why do I need this test?

You may need this test if you are pregnant and it is part of your routine prenatal exams.

If you aren't immune to rubella, you can be vaccinated against the infection. But the shot should not be given to women who are already pregnant. Women should not get pregnant for at least a month after having a rubella vaccine.

What other tests might I have along with this test?

If you are pregnant, your healthcare provider may order a series of tests to look at your overall health. Your provider may also check for:

• Blood type (A, B, AB, or O)

• Rh factor (Rh positive or negative)

• Glucose

• Iron and hemoglobin levels

• Sexually transmitted diseases

• Toxoplasmosis

• Inherited diseases, such as hypercholesterolemia, cystic fibrosis, sickle-cell anemia, thalassemia, and Tay-Sachs disease

What do my test results mean?

Test results may vary depending on your age, gender, health history, the method used for the test, and other things. Your test results may not mean you have a problem. Ask your healthcare provider what your test results mean for you. 

Normal results are positive, meaning that you have enough antibodies to give immunity against the rubella virus. Negative results mean that you don't have enough antibodies.

If you have rheumatoid arthritis or mononucleosis, you may have a false-positive result. If your immune system does not work the way it should, this test may give inaccurate results.

How is this test done?

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

When a blood sample is taken from a baby, it is usually drawn from the heel or, in a newborn, from the umbilical cord.

Does this test pose any risks?

Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore. 

What might affect my test results?

If you've been treated for an immune system disorder or had a transfusion, you may get a false-positive result. People who have been exposed to parvovirus may also get false-positive results.

How do I get ready for the test?

You don't need to prepare for this test. Be sure your healthcare provider knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.