Antibodies against Human Herpesvirus 8 in Black South African Patients with Cancer

Abstract

Background Infection with human herpesvirus 8 (HHV-8) has been consistently linked to Kaposi’s sar- coma, but its mode of transmission, association with other cancers, and interaction with the human im- munodeficiency virus type 1 (HIV-1) are largely un- known. Methods Between January 1992 and December 1997, we interviewed 3591 black patients with cancer in Johannesburg and Soweto, South Africa. Blood was tested for antibodies against HIV-1 and HHV-8 in 3344 of the patients. Antibodies against HHV-8 were detected with an indirect immunofluorescence as- say. The intensity of the fluorescent signal correlated well with the titers of antibodies (P<0.001). The rela- tions among the presence of anti–HHV-8 antibodies, sociodemographic and behavioral factors, type of cancer, and the presence or absence of coexistent HIV-1 infection were examined with the use of un- conditional logistic-regression models. Results Among the 3293 subjects with cancers other than Kaposi’s sarcoma, the standardized sero- prevalence of antibodies against HHV-8 was 32 per- cent, which did not differ significantly from the standardized seroprevalence among black blood do- nors. Among these 3293 patients, the prevalence of antibodies against HHV-8 increased with increasing age (P<0.001) and an increasing number of sexual partners (P=0.05) and decreased with increasing years of education (P=0.007); it was not strongly as- sociated with HIV-1 infection. Anti–HHV-8 antibodies were more frequent among black than white blood donors (P<0.001). Among the 51 patients with Kapo- si’s sarcoma, the standardized seroprevalence of an- tibodies against HHV-8 was 83 percent, significantly higher than the prevalence among those without Ka- posi’s sarcoma (P<0.001). For 16 other specific types of cancer, including multiple myeloma (108 cases) and prostate cancer (202 cases), the variation in the standardized seroprevalence of antibodies against HHV-8 was not remarkable. At a given intensity of fluorescence of anti–HHV-8 antibodies, Kaposi’s sar- coma was more frequent among HIV-1–positive pa- tients than among those who were HIV-1–negative (P<0.001). Conclusions Among black patients with cancer in South Africa, the seroprevalence of anti–HHV-8 anti- bodies is high and is specifically associated with Ka- posi’s sarcoma, particularly at high titers.