High seroprevalence of antibodies to human herpesvirus-8 in Egyptian children: Evidence of nonsexual transmission

Background: In western countries, human herpesvirus-8 (HHV-8) appears to be transmitted mainly by sexual contact, To evaluate the role of other transm ission routes, especially in developing countries, we estimated the seropre valence of HHV-8 in Egyptian children, who, if seropositive, would have acq uired the virus through a nonsexual route. Methods: Sera from 196 children (<1-12 years of age), 20 adolescents (13-20 years of age), and 30 young adu lts (21-25 years of age) attending a vaccination program in Alexandria, Egy pt, were studied. Immunofluorescence assays were used to detect antibodies against HHV-8 lytic-phase antigens (anti-lytic) and latent-phase antigens ( anti-latent), Antibodies against Epstein-Barr virus viral cap antigen, cyto megalovirus, and HHV-6 were detected by enzyme-linked immunosorbent assays. Seroprevalence of these herpesviruses was calculated after stratifying the subjects by age. Results: Anti-lytic and anti-latent HHV-8 antibodies were detected in 44.7% and 8.5% of the study participants, respectively. The pr evalence of anti-lytic antibodies tended to increase with age, exceeding 50 % in children older than 6 years; once children reached the age of 10 years , the prevalence tended to stabilize. The seroprevalence of other herpesvir uses tended to be higher than that of HHV-8, ranging from approximately 83% to more than 97% in the 9- to 12-year age group. One- to 3-year-old childr en had higher titers of antilytic HHV-8 antibodies than children in the oth er age groups, Anti-latent antibodies were more frequently detected in indi viduals with high anti-lytic antibody titers, Conclusions: HHV-8 antibodies are highly prevalent in Egyptian children, suggesting that, in developing countries, HHV-8 infection may be acquired early in life through routes oth er than sexual transmission, The lower seroprevalence of HHV-8 relative to that of the other herpesviruses suggests that HHV-8 is less transmissible t han other common herpesviruses.