Ringworm, often confused with rubella, occurs predominantly in childhood and is then often noticeable because children have intensely red cheeks. The causative agent, parvovirus B19, is unrelated to the rubella virus. Like rubella, however, ringworm is particularly dangerous. If a pregnant woman becomes infected, the unborn child may suffer from water retention, for example in the abdomen, due to an infectious anemia, or it may lead to heart failure (so-called hydrops fetalis): the child may die in the womb as a result of the infection. Professor Susanne Modrow, head of the Consiliary Laboratory for Parvoviruses, Institute for Medical Microbiology and Hygiene at the University of Regensburg, provides information on how common this event is and what you should know about ringworm if you are expecting a child.
How common is the disease in adults or in pregnant women?
Prof. Modrow: According to a representative study, about 65 percent of 18- to 19-year-olds have already had ringworm, and this figure rises to 80 percent among those over 70. It can be assumed that about 70 percent of pregnant women are protected from parvovirus B19 infection because they have had the infection before.
By what symptoms do you notice that you are infected?
Prof. Modrow: The course of the disease in children and in adults is somewhat different. In children, red cheeks are noticeable symptoms. This is often the first sign; one to two days later, a garland-shaped rash appears on the arms, legs and trunk, and there is a slight fever, listlessness, fatigue and malaise. Even children can suffer from joint inflammation. However, these are more severe when adults go through the disease, the joint pain and swelling can last for weeks to months, and in rare cases can even trigger rheumatoid disease. The classic rash, however, is often absent.
What are the effects of ringworm in pregnancy?
Prof. Modrow: This depends crucially on the time of the disease. In the case of infection up to about the eighth week of pregnancy, spontaneous miscarriage usually occurs. Infections of pregnant women between the 8th and 20th week of pregnancy are particularly problematic. Then, about four to ten weeks after the mother’s infection, hydrops fetalis may occur in the child. About three to nine percent of children born to mothers who experience an acute parvovirus infection during this time are affected. Unlike rubella, the children do not develop congenital damage: They either die in the womb or are born healthy. Women who become ill after the 20th week of pregnancy need not fear any risk to their child.
Is there treatment if an unborn baby is infected and how is this diagnosed?
Prof. Modrow: Sometimes the women themselves discover that something is wrong because the baby moves less. Most of the time, however, Doppler sonography during prenatal care determines that the child has anemia. In these cases, a blood test is immediately performed in the woman (IgM antibodies + viral DNA in the serum) to clarify whether there is an acute infection. In the child, the hemoglobin level is examined. Treatment consists of an immediate blood transfusion via the umbilical cord vein. This can save the child, who is born healthy.
What advice can you give to a pregnant woman?
Prof. Modrow: First of all, the advice not to panic if there has been contact with someone suffering from ringworm – often, by the way, these are one’s own children who bring the disease home from kindergarten, for example. However, this should immediately be cause for a blood test, especially if the contact existed in the 8th to 20th week of pregnancy. If you have a test done before or at the beginning of pregnancy, you can usually be quite relaxed in these situations, because more than two-thirds of pregnant women have already had the disease and thus have lifelong immunity. However, the test is not paid for by the health insurance companies. But even if you don’t know whether you’ve had ringworm, there’s no need to panic, because well over 90 percent of acute infections during pregnancy are unproblematic. And in the remaining cases, there is the possibility of therapy in the unborn child.
