Frequent presence of a novel herpesvirus genome in lesions of human immunodeficiency virus-negative Kaposi's sarcoma.

While Kaposi's sarcoma (KS) is extremely common in homosexual men infected with human immunodeficiency virus (HIV), it is also found in several clinical settings in which HIV infection is absent. Recently, sequences from the genome of a novel member of the herpesvirus family have been identified within KS biopsies in the AIDS-associated form of the disease. The presence of these sequences was sought in 6 cases of HIV-negative KS, including 4 cases of endemic KS from Africa, and was found in 5 of the 6. These findings strengthen the association between infection with this virus and the development of KS and argue against the notion that this association is simply the result of opportunistic superinfection of profoundly immunodeficient hosts.