Parvovirus

Does this test have other names?

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

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 (erythema infectiosum).

The virus usually causes only mild illness in children. It can be dangerous for pregnant women or people with a weak immune system. This is because they may not have 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 B19 will have no symptoms. Many children develop a fever, a red rash on their cheeks that looks like a slap mark, runny nose, diarrhea, and a generalized 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 healthcare provider is likely to order this test if you are pregnant or have a weak immune system, and you suspect you have been exposed to fifth disease. If your immune system is weak, the virus could trigger more serious health problems. People with certain types of anemia or a weak immune system 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 healthcare provider figure out the right treatment if you become ill. 

What other tests might I have along with this test?

Your healthcare 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?

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

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

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?

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. 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 illegal drugs you may use.