What is Parvovirus B19?

Parvovirus B19 is a virus that commonly infects humans; about 50% of all adults have been infected sometime during their childhood or adolescence. Parvovirus B19 infects only humans. There is animal parvovirus, but they do not infect humans. Therefore, a person cannot catch ParvovirusB19 from a dog or a cat.

Humans are the only known hosts of parvovirus B19 infection. Outbreaks commonly occur among school-age children, especially in the winter and spring. Secondary spread is common, occurring in about 50% of susceptible household contacts. Transmission is felt to be through respiratory secretions.

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 – 10 days. Once a child recovers from parvovirus infection, he or she will develop 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. They may develop a rash, or joint pain, or swelling, or both. The joint symptoms usually resolve in a week or two, but they can 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.

Is there any way I can keep from being infected with Parvovirus B19 during my pregnancy?

There is no vaccine or medication that prevents parvovirus B19 infection. Frequent hand washing is recommended as a practical and probably effective method to reduce the spread of parvovirus. Excluding persons with fifth disease from work, child care centers, schools, or other settings is not likely to prevent the spread of parvovirus, since ill persons are contagious before they develop the characteristic rash.

Do your best to stay away from people with viral-like symptoms

•  Always wash your hands after wiping noses or touching tissues of kids who are sick or who have been around others who are sick.
•  Do not share food, eating utensils, or drinking glasses.

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

Usually, there are not serious complications 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.

However, parvovirus B19 infection sometimes can 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 are exposed to someone with fifth disease, contact your healthcare provider and request a blood test to see if you have become infected with parvovirus B19. A blood test for parvovirus may show:

(1). You are immune to parvovirus B19 and have no sign of recent infection; (2). You are not immune and have not yet been infected;

(3). You have had a recent infection.

If you are immune, then you have nothing further to be concerned about. If you are not immune and not yet infected, then you should try to avoid further exposure to fifth disease. If you have had a recent infection, discuss your plan of care with your healthcare provider.

There is no universally recommended approach to monitoring a pregnant woman who has a documented parvovirus B19 infection. You may be referred to a perinatalogist for ultrasounds and possibly serial blood  tests. If the unborn baby appears to be ill, other diagnostic and treatment options are available, and your provider will discuss these options with you and their potential benefits and risks.

Talk to your healthcare provider if you have any questions or concerns regarding Fifth Disease.

Centers for Disease Control. Risks associated with human parvovirus B19 infection. MMWR 1989;38:81-97.