Background: Human herpes virus 8 (HHV-8), a gamma herpes virus, is the etiological agent for Kaposi sarcoma (KS). HIV-infected adults with advanced immunodeficiency are at risk. Prevalence data of HHV-8 infection in HIV-infected children living in non-endemic areas are limited. Serologic studies indicate low seroprevalence rates of 3–4% for healthy children living in United States and Germany [1]. Purpose of the study: The aim of the study was to determine the seroprevalence of HHV-8 antibodies among vertically HIV-infected pediatric patients in Germany and to evaluate their association with age, gender, ethnicity, and other demographic factors. Methods: In 2012, a multi-center cross-sectional study was conducted in four University Hospitals in Germany. Stored frozen serum specimens obtained from vertically HIV-infected children and adolescents were tested for antibodies against lytic and latent HHV-8 antigens. Data on patients' demographic characteristics and medical history were recorded. Results: A total of 214 HIV-infected children and adolescents (105 males, 109 females) were included. The median age was 10.2 years (range 1 months–22.6 years). A high proportion of these children (62%) was born in Western Europe, whereas 65% (139/214) of their mothers were born in countries outside Western Europe. The majoritiy (91%) of the children had been treated with highly active antiretroviral therapy and 55.2% (116/210) had a HIV-viral load<50 copies/mL. The median CD4 cell count was 1000/L (range 3–4400). The overall seroprevalence of HHV-8 antibodies was 23.8% (51/214). Seroprevalence rates did not show significant differences between age or gender. In the group of young children aged 1 month to 35 months, 19.4% (46/31) had HHV-8 antibodies, compared to 25% (25/100) in children aged 36 months to 11 years, and 24.1% (20/83) children 12 years and older. In the study group, seroprevalence rates were significantly lower in children who were born in Western Europe (p <0.01) compared to those born in Africa, Asia, or Eastern Europe. Clinical symptoms of HHV-8 infection were reported to be uncommon; only one child had a history of KS at 2 years of age. Conclusions: Vertically HIV-infected pediatric patients living in Germany showed a high HHV-8 seroprevalence of 23.8%. These rates were higher as expected in the normal pediatric population. The findings suggest that HHV-8 infection occurred already in the first years of life
