Human cytomegalovirus (HCMV), commonly known as CMV, is a widespread virus from the beta-herpesvirus family that causes lifelong infection. Once a person is infected, the virus remains in the body in a dormant state and may reactivate later. CMV is extremely common worldwide, with infection rates ranging from 55% to nearly 100%, depending on age, geography, and socioeconomic conditions.
Most healthy people experience no symptoms or only mild, flu-like illness during primary infection. However, CMV can cause severe and life-threatening disease in individuals with weakened immune systems, including newborns, pregnant women, organ transplant recipients, and people living with HIV/AIDS.
CMV and High-Risk Groups
CMV is the leading infectious cause of congenital abnormalities in developed countries, affecting approximately 1–2.5% of all live births. The virus can cross the placenta during pregnancy and infect the fetus, even if the mother has no symptoms.
Complications of congenital CMV may include:
• Low birth weight
• Hearing and vision loss
• Microcephaly
• Enlarged liver and spleen
• Developmental and cognitive delays
In immunocompromised adults, CMV can cause pneumonia, gastrointestinal disease, retinitis, neurological complications, and may contribute to transplant rejection.
Transmission of CMV
CMV spreads through direct contact with infected body fluids, such as saliva, urine, blood, breast milk, and sexual fluids. Young children are a common source of infection due to prolonged viral shedding.
Main routes of transmission include:
• Close contact with saliva or urine
• Sexual contact
• Breastfeeding
• Blood transfusions and organ transplants
Diagnosis, Treatment, and Prevention
CMV is diagnosed using blood, urine, or saliva tests. Treatment with antiviral medications (ganciclovir or valganciclovir) is usually limited to high-risk patients, as these drugs cannot reverse existing damage and may cause side effects. Prevention focuses on reducing exposure, especially during pregnancy:
• Strict hand hygiene
• Avoiding sharing utensils with young children
• Practicing safe sex
• Medical monitoring after transplantation
Conclusion
Human cytomegalovirus is usually harmless in healthy individuals but can cause serious disease in vulnerable populations. Improved understanding of CMV biology and immune interactions is essential for better therapies and the development of an effective vaccine.