Background: A potential source of primary Epstein-Barr virus (EBV) infection for young children is parental oral secretions. If parents who identify with racial/ethnic categories other than white have a higher prevalence of oral EBV DNA, this difference could explain why their children acquire primary EBV infection at an earlier age than white children.
Methods: To test this hypothesis, we recruited parents who brought their children <8 years old to routine clinic visits, and tested the parents' oral washes for EBV DNA by real-time polymerase chain reaction. Positive samples were assayed for encapsidated EBV DNA, which is potentially infectious, versus naked EBV DNA, which is not infectious.
Results: Overall, 221/800 parents (28%) had EBV DNA in their oral washes. Oral EBV DNA was more prevalent in parents who identified as non-white as compared with white parents (P = .0004), and was more prevalent in male vs female parents (P = .04). The mean quantity of EBV DNA in positive samples was 5000 copies/mL. Encapsidated viral DNA comprised 40.3% of the total EBV DNA found in parental oral secretions.
Conclusions: Our data support the hypothesis that parents could be a source of virus for their young children, because 28% of parents had a mean of 5000 EBV copies/mL of oral wash and 40.3% of the EBV DNA was encapsidated. The higher prevalence of EBV DNA in non-white parents could explain why their children acquire EBV at an earlier age than children of white parents.