Molecular epidemiology of human Herpesviruses types 1-6 and 8 among Greek blood donors

Background: Human Herpesviruses (HHVs) maintain life-long latent persistence in the majority of the adult population including blood donors. The necessity for their study resides in the potential risk of transfusion-associated infection and the subsequent complications in the immunocompromised host. We aimed to assess the prevalence of HHVs types 1-6 and 8 among healthy blood donors of Thessaly prefecture in order to evaluate the frequency distribution of HHVs in Greek population and to ascertain possible correlations with demographic factors. Materials and Methods: Polymerase chain reaction (PCR) detection of HHVs DNA was determined in 401 randomly selected consecutive blood donors of Central Greece. Epidemiological data were recorded through a well structured questionnaire. Results: The overall PCR positivity for HHVs was 25.4%. HHVs types 1-3 were not detected in any donor sample. A specimen with high level of HHV-6 DNA (1 580 400 copies per mL) was recorded. HHV-4 DNA positivity was significantly associated with rural residency. Conclusion: HHV-4 DNA is commonly detected in whole blood specimens of healthy individuals. HHVs types 5, 6 and 8 are rarely detected. However, the existence of a donor sample with high HHV-6 viral load raises questions regarding the potential risk of HHV-6 blood-borne infection and the safety of blood products.