Clinical samples and antibodies

Human serum samples were collected within a prospective cohort study at the Medical University of Vienna, Austria (cohort I) and the Red Cross Vienna, Austria (cohort II). Written informed consent was obtained from all patients at the time of enrolment. The study protocol was approved by the local institutional review board of the Medical University of Vienna in accordance with the Declaration of Helsinki (EK26/2012). Cohort I included healthy volunteers (n = 18) and patients with primary CMV infection (n = 20). The diagnosis of primary CMV infection was established by the presence of CMV-specific IgM and CMV-DNA in plasma and clinical signs and symptoms compatible with infectious mononucleosis. None of the patients had a history of immunodeficiency or an other underlying disease. The median interval between onset of CMV disease and blood collection was 25 days, mean age of these patients was 40 years. Cohort II included healthy blood donors (n = 150). The mean age of these blood donors was 54 years (SD, 11 years; range, 24 to 74 years) and 88% (132 of 150) of these donors were male.