Background: Human herpesvirus 8 (HHV8) is considered as the infectious cofactor involved in the pathogenesis of Kaposi's sarcoma (KS). Its seroprevalence and modes of transmission in the general population are still undetermined.
Objectives: We aimed to estimate the prevalence of HHV8 infection in a population at low risk for sexually transmitted diseases.
Methods: We conducted a seroepidemiological survey on randomly selected individuals attending the dermatology department of a teaching hospital in Rome. Of 257 patients, 248 had their blood analysed for anti-HHV8 antibodies and 201 completed a standardized interview. Serological analysis was performed by an immunofluorescence assay able to detect antilytic antibodies.
Results: We found an overall seroprevalence of 15.7% (95% confidence interval, CI 11.4-20.9%), similar in men and women (15.1% vs. 16.3%) and higher at older ages. Seropositivity was not related to sexual habits, while it was significantly associated with a history of hepatitis (seroprevalence 34.6%, adjusted odds ratio, OR 4.08, 95% CI 1.52-11.00) and with a diagnosis of non-melanoma skin cancer (42.9%, OR 4.20, 95% CI 1.26-14.02) or atypical naevi (35.3%, OR 6.21, 95% CI 1.85-20.86).
Conclusions: Our data suggest that a non-sexual mode of transmission of HHV8 infection is plausible in an Italian population at low risk for sexually transmitted diseases and that other factors, besides differences in prevalence of HHV8 infection, may be involved in the epidemiology of classical KS. The unexpectedly high seropositivity rates in subjects with non-melanoma skin cancer and atypical naevi should be viewed with caution and require confirmation.