What is CMV?
Cytomegaly is an infectious disease caused by cytomegalovirus (CMV). CMV is one of the herpes viruses. Like all herpes viruses, the virus remains in the body for life after the initial infection and can be reactivated under certain circumstances. Reinfection is also possible. In most cases, the initial infection goes unnoticed. CMV infection is of clinical importance especially in pregnancy and in people with reduced immune defense, for example after transplants, in the case of tumor diseases or AIDS.
In pregnant women, the virus can be transmitted to the unborn child (congenital CMV infection) and may cause serious damage. The risk of mother-to-child transmission is much higher after initial infection than after reinfection or reactivation. Congenital CMV infection is the most common infectious cause of intellectual disability and non-inherited hearing disorders in childhood.
Transmission of CMV in pregnancy
The cytomegalovirus is primarily transmitted by smear infections and breastfeeding. The cytomegalovirus can be transmitted from mother to unborn child throughout pregnancy. If an initial CMV infection occurs in the first or second trimester of pregnancy, the child becomes infected in 30–40% of the cases. If this occurs in the third trimester of pregnancy, 50–70% of the children are infected.
Characteristics of CMV
In many cases, individuals do not realize that they are infected with CMV. This also applies to pregnant women. Only 20% of the women show unspecific or flu-like symptoms such as headache and body aches, swelling of the lymph nodes, fever, and fatigue. Reactivations and reinfections are usually without symptoms.
10 out of 100 children who have been infected with CMV have symptoms at birth such as:
• Low birth weight and/or premature birth
• Jaundice (yellowing of skin and eyes)
• Bleeding into the skin (petechiae)
• Enlargement of the liver and spleen
• Microcephaly (head too small)
• Calcifications in the brain
• Hearing defects
• Eye damage
A severe physical and mental handicap of the child is possible. Many children that were infected in the womb are healthy at birth. A routine check-up should be done regularly in congenitally infected children to examine for further symptoms.
Diagnostic approach
There are various methods to test for a CMV infection. When a first infection is diagnosed, the development of the child is monitored by regular ultrasound examinations. An examination of the amniotic fluid can determine whether the unborn child is infected.
All newborns of women with suspected CMV infection during pregnancy and all newborns with signs of illness should be examined for CMV in urine and saliva. This should be done immediately after birth. If the examination is carried out later, it may no longer be possible to distinguish between a congenital infection or CMV.
Prevention & Therapy
There is no approved treatment for CMV infection during pregnancy that safely reduces the risk of the virus being transmitted from the mother to the child, or the risk of damage to the child. After a detailed consultation, a so-called “off-label” treatment with CMV antibodies can be considered in the case of an initial CMV infection. The treatment aims to reduce the risk of transmission of the CMV infection from the mother to the unborn child. There is evidence for the benefits of this therapy. “Off-label” means that the medication is officially not approved for use in pregnancy and that use must be weighed in each case.
Antiviral medication is generally not used in people with CMV infection and normal physical defense. This also applies to pregnant women. If the unborn child is diagnosed with CMV infection, however, antiviral therapy can be used in pregnancy in individual cases. This requires detailed information from specialists and a consideration of the benefits and risks since antiviral treatment in pregnant women is always “off-label”. Therefore, the drug has not been sufficiently tested for this area of application.
Antiviral therapy is not currently recommended for newborns with congenital CMV infection who show no signs of disease. Antiviral therapy should be considered for newborns with disease signs, especially if the brain is affected. A prerequisite for this “off-label” treatment is a careful education of the parents about the expected benefits and possible side effects.
Insurance coverage on CMV
If you are covered for both inpatient and outpatient treatments (INP & OPD) your health insurance will likely cover for your routine consultations, treatments, and laboratory tests for CMV.
Consultations for your pregnancies will fall under “maternity” cover. Any medical costs in regards to your pregnancy, such as routine pregnancy check-up, ultrasound, etc. will not be covered by standard in and outpatient policy.
