Mixed patterns of transmission of human herpesvirus-8 (Kaposi's sarcoma-associated herpesvirus) in Malawian families

To study transmission patterns of human herpes-virus-8 (HHV-8) (Kaposi's sarcoma-associated herpesvirus) in families in Malawi, nucleotide sequences derived from two hypervariable loci of the HHV-8 genome, the V1 and V2 regions of open reading frame K1 (K1/V1 and K1/V2, respectively), were amplified from blood and mouth rinse samples of 22 patients with treated and untreated Kaposi's sarcoma (KS) and their first-degree relatives (n = 67). In patients with KS, vincristine therapy was significantly associated with non-detectability of circulating, but not oral, K1/V1 DNA. Intra-familial K1/V1 phylogenetic comparisons of eight families were possible. Both identical and non-identical sequences were observed between family members, suggesting transmission of HHV-8 along both intra-and extra-familial transmission routes.