Family saliva sharing behaviors and age of human herpesvirus-6B infection

Abstract

Transmission of human herpesvirus (HHV-6) type B is hypothesized to occur via saliva. We sought to determine whether behaviors promoting saliva sharing were associated with HHV-6B infection. Parents of young children participating in a natural history study of HHV-6B were asked to complete a questionnaire focused on family behaviors that result in saliva sharing. Of 111 surveys, 109 (98%) were completed. Of the 109 participants, 37 (34%) were infected with HHV-6 before 1 year of age. Having older siblings (adjusted OR 4.1, 95% CI 1.5, 11.8) and receipt of parental saliva when kissed (adjusted OR 5.1, 95% CI 1.8, 14.5) were independently associated with younger age of HHV-6 infection. Dose-response relationships were demonstrated between HHV-6 infection before 1 year and both number of siblings and the frequency that the child received parental saliva when being kissed (p=0.006 and p=0.002, respectively). Having older siblings and parents who shared saliva increased risk of HHV-6B acquisition in children. These data support the hypothesis that HHV-6 is transmitted primarily via saliva within families.