B19 infection and pregnancy

What is parvovirus B19?

Parvovirus B19 is a virus that commonly infects humans; about 50% of all adults have been infected sometime during childhood or adolescence. Parvovirus B19 infects only humans. There are also animal parvoviruses, but they do not infect humans. Therefore, a person cannot catch parvovirus B19 from a dog or cat.

What illnesses does parvovirus B19 infection cause?

The most common illness caused by parvovirus B19 infection is "fifth disease," a mild rash illness that occurs most often in children. The ill child typically has a "slapped-cheek" rash on the face and a lacy red rash on the trunk and limbs. Occasionally, the rash may itch. The child is usually not very ill, and the rash resolves in 7 to 10 days. Once a child recovers from parvovirus infection, he or she develops lasting immunity, which means that the child is protected against future infection. An adult who has not previously been infected with parvovirus B19 can be infected and become ill, and develop a rash, or joint pain or swelling, or both. The joint symptoms usually resolve in a week or two, but they may last several months.

Are these illnesses serious?

Fifth disease is usually a mild illness. It resolves without medical treatment among children and adults who are otherwise healthy. Joint pain and swelling in adults usually resolve without long-term disability. During outbreaks of fifth disease, about 20% of adults and children are infected without getting any symptoms at all.

I've recently been exposed to a child with fifth disease. How will this affect my pregnancy?

Usually, there is no serious complication for a pregnant woman or her baby because of exposure to a person with fifth disease. About 50% of women are already immune to parvovirus B19, and these women and their babies are protected from infection and illness. Even if a woman is susceptible and gets infected with parvovirus B19, she usually experiences only a mild illness. Likewise, her unborn baby usually does not have any problems attributable to parvovirus B19 infection. Sometimes, however, parvovirus B19 infection will cause the unborn baby to have severe anemia and the woman may have a miscarriage. This occurs in less than 5% of all pregnant women who are infected with parvovirus B19 and occurs more commonly during the first half of pregnancy. There is no evidence that parvovirus B19 infection causes birth defects or mental retardation.

If I've been exposed to someone with fifth disease, what should I do?

If you have been in contact with someone who has read more