Parvovirus

Does this test have other names?

Parvovirus B19-specific IgG antibody, parvovirus B19 IgM, parvovirus B19 antibody

What is this test?

This is a blood test to check for current or past infections with parvovirus 19. This virus causes the common children's illness known as fifth disease, or erythema infectiosum.

The virus usually causes only mild illness in children. It can be dangerous for pregnant women or people with a weakened immune system, however, because they may lack the antibodies to fight off a parvovirus infection. 

Why do I need this test?

You may need this test if you show symptoms of fifth disease. Some people who are exposed to parvovirus 19 will have no symptoms at all. Many children develop a slight fever, a red rash on their cheeks that resembles a slap mark, and a lacy rash. Some also have joint pain. Adults often have joint pain and swelling, itching, fever, and a lacy rash over their trunk and limbs.

Your health care provider is likely to order this test if you are pregnant or have a weakened immune system, and you suspect you have been exposed to fifth disease. If your immunity is weak, the virus could trigger more serious health problems. People with certain types of anemia can develop a severe, life-threatening type of anemia.

Pregnant women who have young children are at higher risk for exposure to the virus, which can infect and seriously harm a fetus.

Knowing you've been exposed to the virus helps your doctor figure out the right treatment if you become ill. 

What other tests might I have along with this test?

Your health care provider may also order a complete blood count if you have HIV, sickle cell disease, an inherited blood disorder called spherocytosis, or other conditions affecting your red blood cells or immunity.

What do my test results mean?

Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.

Your results show whether you have antibodies to parvovirus. If your results are negative, it means you have not been exposed. If your results are positive, you have been exposed to parvovirus and have the antibodies to it. 

How is this test done?

The test requires a blood sample, which is drawn through a needle from a vein in your arm.

Does this test pose any risks?

Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore. 

What might affect my test results?

Sometimes you can get a false-positive result if you have rheumatoid factor, antinuclear antibodies, or antibodies to the Epstein-Barr virus.

How do I get ready for this test?

You don't need to prepare for this test.