SEXUAL TRANSMISSION AND THE NATURAL-HISTORY OF HUMAN-HERPESVIRUS-8 INFECTION

Background Although human herpesvirus 8 (HHV-8) has been suspected to be the etiologic agent of Kaposi's sarcoma, little is known about its seroprevalence in the population, its modes of transmission, and its n atural history. Methods The San Francisco Men's Wealth Study, begun in 1984, is a study of a population-based sample of men in an area with a high incidence of human immunodeficiency virus (HIV) infection. We s tudied all 400 men infected at base line with HIV and a sample of 400 uninfected men, Base-line serum samples were assayed for antibodies to HHV-8 latency-associated nuclear antigen (anti-LANA). In addition to the seroprevalence and risk factors for anti-LANA seropositivity, we a nalyzed the time to the development of Kaposi's sarcoma. Results Anti- LANA antibodies were: found in 223 of 593 men (37.6 percent) who repor ted any homosexual activity in the previous five years and in none of 195 exclusively heterosexual men, Anti-LANA seropositivity correlated with a history of sexually transmitted diseases and had a linear assoc iation with the number of male sexual-intercourse partners. Among the men who were infected with both HIV and HHV-8 at base line, the 10-yea r probability of Kaposi's sarcoma was 49.6 percent, Base-line anti-LAN A seropositivity preceded and was independently associated with subseq uent Kaposi's sarcoma, even after adjustment; for CD4 cell counts and the number of homosexual partners. Conclusions The prevalence of HHV-8 infection is high among homosexual men, correlates with the number of homosexual partners, and is temporally and independently associated w ith Kaposi's sarcoma, These observations are further evidence that HHV -8 has an etiologic Pole in Kaposi's sarcoma and is sexually transmitt ed among men. (C) 1998 Massachusetts Medical Society.