Behavioral, Virologic, and Immunologic Factors Associated with Acquisition and Severity of Primary Epstein-Barr Virus Infection in University Students.

Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455.
The Journal of Infectious Diseases (Impact Factor: 5.78). 10/2012; DOI: 10.1093/infdis/jis646
Source: PubMed

ABSTRACT Background. University students were studied prospectively to determine the incidence and risk factors for acquisition of primary Epstein-Barr virus (EBV) infection and the virologic and immune correlates of disease severity.Methods. EBV antibody-negative freshmen participated in monthly surveillance until graduation. If antibodies developed, proximate samples were assayed for viral load by PCR. Lymphocyte and NK cell numbers and activation were measured by flow cytometry, and plasma cytokines by Luminex.Results. Of 546 students screened, 202 (37%) were antibody-negative and 143 of them enrolled. During a median of 3 years of observation, 66 subjects experienced primary infection. Of these, 77% had infectious mononucleosis, 12% had atypical symptoms, and 11% were asymptomatic. Subjects reporting deep kissing with or without coitus had the same higher risk of infection than those reporting no kissing (P < .01). Viremia was transient but median oral shedding was 175 days. Increases were observed in NK and CD8 but not CD4 T cell numbers during acute infection. Severity of illness correlated positively with both blood EBV load (P=0.015) and CD8 lymphocytosis (P=0.0003).Conclusions. Kissing was a significant risk for primary EBV infection; 89% of infections were symptomatic; blood viral load and CD8 lymphocytosis correlated with disease severity.

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