Expert: cytomegalovirus is dangerous for the fetus; testing of pregnant women is necessary

Cytomegalovirus (CMV) is one of the viruses that can damage the fetus and cause permanent damage to the child's health, reminds Dr. Tadeusz Issat from the Institute of Mother and Child in Warsaw. However, most pregnant women in Poland are not tested for CMV.

Only in recent years have research results emerged indicating the safety and effectiveness of the antiviral drug valacyclovir as a potential treatment for cytomegalovirus in pregnant women. A clinical trial is currently underway at the Institute of Mother and Child, in which specialists are examining whether using a lower dose of this drug will reduce the risk of transmitting the virus to the fetus.

Cytomegalovirus (CMV) is a herpes virus that most people are infected with in childhood. In healthy individuals, it is usually asymptomatic. The problem arises when a woman first encounters the virus during pregnancy (known as primary infection during pregnancy). In this case, especially if infection occurs in the first trimester, there is a risk of the virus crossing the placenta and infecting the fetus.

CMV is transmitted through contact with saliva, urine and other secretions – most often in the home environment, e.g. from a child attending kindergarten or nursery.

Infection in pregnant women may be asymptomatic or produce nonspecific symptoms typical of a mild cold, such as swollen lymph nodes, runny nose, cough, joint pain, or fever. "This infection is very common, yet overlooked in perinatal care. Meanwhile, primary CMV infection during pregnancy can have very serious consequences for the child's health," emphasized Dr. Tadeusz Issat, head of the Obstetrics and Gynecology Clinic at the Institute of Mother and Child in Warsaw, quoted in a press release sent to PAP. Complications of fetal CMV infection include hearing loss, brain damage and neurological disorders, epilepsy, and delayed post-traumatic motor development (permanent disability).

In Poland, up to 2,500 babies are born with congenital cytomegalovirus (CMV) each year. Most infections remain undetected during pregnancy. This is due, in part, to the fact that CMV testing for pregnant women is neither mandatory nor reimbursed in our country, even though experts believe the risk of infection is higher than, for example, toxoplasmosis.

The low interest in incorporating CMV testing into standard pregnancy diagnostics may have been due to the lack of effective treatment for many years, the press release stated. Pregnant women diagnosed with CMV infection "had no therapeutic options or were, and continue to be, referred for therapy whose effectiveness has not been confirmed."

The Institute of Mother and Child is currently conducting a clinical trial, POL PRENATAL CMV, which offers free CMV testing for women up to 14 weeks of pregnancy. If the result indicates a recent primary infection, the patient may also be eligible for free antiviral treatment with valacyclovir. The effectiveness and safety of the treatment are monitored.

"As part of a clinical trial, we are evaluating the use of valacyclovir, an antiviral drug not routinely used in obstetrics. We are investigating whether a lower dose can be used in cases of primary cytomegalovirus infection, which will be safe for pregnant women while also reducing the risk of transmitting the virus to the fetus," explained Dr. Issat.

This is important because treatment is currently not reimbursed, and the costs of treatment with standard doses are high. If a lower dose of valacyclovir proves equally effective, the treatment will be more affordable.

This is the first program of its kind in Poland and the second in the world to offer not only diagnostics but also treatment. Experts hope that if the study proves successful, it could contribute to changing the standards of perinatal care, enabling early detection of CMV infection and effective intervention during pregnancy.

"Thanks to our program, women can be diagnosed and treated before damage occurs to the developing fetus. But this is still not enough—systemic changes are needed," Dr. Issat emphasized. This includes introducing the CMV test into routine diagnostics for pregnant women, like HIV or toxoplasmosis tests. This simple test, followed by treatment, can reduce serious risks to the child's health.

Magdalena was the first patient to receive valacyclovir as part of the POL PRENATAL CMV study. She was diagnosed with CMV infection in the 10th week of pregnancy. Thanks to the treatment, her son, Jaś, was born healthy.

Experts believe that knowledge about CMV should be part of prenatal education. CMV is one of the most common viruses that pose a threat to the fetus. Despite this, awareness of the risks of contracting this virus during pregnancy remains very low among both patients and physicians.

The POL PRENATAL CMV project is publicly funded by the Medical Research Agency. The study is aimed at adult women in early pregnancy who have been confirmed to have CMV antibodies. More information about the study can be found at szkoleniacmv.pl. (PAP)

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