Detection of human herpesvirus 8 DNA sequences in tissues and bodily fluids

TLDR: The data suggest that saliva may be more important than semen or stool in the sexual transmission of HHV-8, and raises the question as to why there is no evidence for bloodborne virus transmission.

Abstract: Human herpesvirus 8 (HHV-8) has been proposed as a sexually transmitted etiologic agent of Kaposi’s sarcoma (KS). In this study, by use of a sensitive polymerase chain reaction assay, HHV-8 DNA was detected in the skin lesions (92%), normal skin (23%), peripheral blood mononuclear cells (PBMC) (46%), plasma (7%), saliva (37%), and semen (12%) but not stool samples from KS patients. The average number of HHV-8 copies per microgram of positive target DNA was 64,000, 9000, 40, 33,000, and 300 for skin, PBMC, plasma, saliva, and semen samples, respectively. Only 1 non-KS donor sample, of saliva, was positive for HHV-8. Sequencing showed 5% divergence among HHV-8 strains. The data suggest that saliva may be more important than semen or stool in the sexual transmission of HHV-8. The relatively high prevalence of HHV-8 in PBMC raises the question as to why there is no evidence for bloodborne virus transmission. Kaposi’s sarcoma (KS) occurs as a mild indolent disease in immunocompetent persons but is an aggressive, lethal disease in immunosuppressed patients, particularly those infected with human immunodeficiency virus (HIV) [1]. Epidemiologic studies suggest that KS is a sexually transmitted disease caused by the newly discovered human herpesvirus 8 (HHV-8) [1, 2]. Subsequently, HHV-8 has been shown to be associated with numerous other tumors, including body cavity lymphomas, angiosarcomas and hemangiomas, premalignant Bowen’s disease, malignant squamous cell carcinomas, and actinic keratosis [2]. HHV-8 positivity has been shown to be more closely linked to HIV-positive patients with homosexuality or bisexuality as their major risk factor for HIV than to patients with other risks [2]. Hence, it has been suggested that HHV-8 may be a sexually transmissible virus, particularly via anal intercourse. The fact that HHV-8 can be found in semen samples and in individual spermatozoa and mononuclear cells present in semen has supported this hypothesis [3]. However, in large-scale or smaller matched studies, the prevalence of HHV-8 in semen has been equal to or less than that found in peripheral blood mono