Currently, medicine knows 11,800 types of different viruses (for comparison, until 2011, only 2,800 types of viruses were discovered), which, according to rough estimates by scientists, is no more than 5–10% of all existing viruses on our planet. From 95 to 100% of the population are infected with the herpes virus, and at different periods of life they become infected with at least one, and more often several types of viruses belonging to the herpesvirus family. In the second half of life, almost all people have antibodies to most human herpesviruses. Of the known human herpesviruses, herpes simplex viruses types 1 (HSV-1) and 2 (HSV-2) are the most frequently mentioned in the medical literature, since both of these viruses are associated with lesions of the skin and mucous membranes, commonly known as herpes simplex. However, only recently the role of human herpes viruses (HHVs) as copathogens causing other serious diseases has been recognized. Roseoloviruses are represented by three different types: HHV-6A, -6B, -7, genetically related to cytomegalovirus (CMV). HHVs have broad cellular tropism in vivo and, like other herpesviruses, cause lifelong latent infection in humans. It is known that all known HHVs are found in the reproductive tract. CMV and HHV-6 can contribute to the occurrence of chronic inflammatory diseases of the urogenital tract and impaired fertility in patients. Recent studies have found that HHV-6A is the cause of primary infertility in 43% of cases, and HHV-6A and -6B in some clinical cases contribute to the development of preeclampsia. The role of Epstein–Barr virus (EHV-4), as well as HHV-6, -7 and -8 in the progression of HIV infection is being actively studied. Laboratory diagnosis of HHV-6 and -7 currently has limitations. The most informative method for detecting HHV is the quantitative determination of viral DNA in the blood, other body fluids and organs using real-time polymerase chain reaction. Numerous questions about HHV-6A, -6B and -7 still remain open, particularly regarding the clinical impact and therapeutic options in immunocompromised patients.

Keywords: impaired fertility, HHV-7, HHV-6A/B, human herpes virus, clinical syndromes, congenital infection, preeclampsia, infertility