Background: About one century ago, was found and described a new virus, which, due to its particular way of damaging cells, was called cytomegalovirus. Human is the only natural source of cytomegalovirus infection. The relevance is that it is a widespread pathology, and due to its ability to “disguise” in the human body, remains unnoticed until the “defect” appears in the body’s immune system. It is especially dangerous for pregnant women, children and people with immunodeficiency. It is one of the most common infections that cause pathology in the fetus and newborns, which, in turn, leads to serious consequences, from disability to child death. There are many ways of cytomegalovirus transmission: airborne, parenteral, domestic contact, sexual and vertical (transplacentally, with aspiration of secretions from the birth canal and natural feeding). The virus is able to have a direct and indirect effect on the body. It is able to independently induce immunosuppression. The article describes the epidemiological data, pathogenesis, clinical manifestations, and modern methods of diagnosis, treatment and prevention of cytomegalovirus infection. Also, some diagnostic problems in immunosuppressive organisms are described. Conclusions: Due to its consequences, namely, children`s disability, death and immunosuppressed people, cytomegalovirus has become a demographic problem. A high infection frequency indicates a low level of social development of the population. More public awareness is needed on the transmission and possible consequences of cytomegalovirus infection.