© 2001 Elsevier Science Inc. All rights reserved. 1047-2797/01/$–see front matter 655 Avenue of the Americas, New York, NY 10010 PII S1047-2797(01)00242-3 INTRODUCTION Following the epidemic of blood transfusion-transmitted human immunodeficiency virus (HIV) in the early 1980s, improvements in the blood donor screening process were implemented to increase the overall safety of the U.S. blood supply (1, 2). Over the last decade, a number of newly identified infectious agents have been added to the list of viruses routinely screened among blood and plasma Seroprevalence of Kaposi’s Sarcoma-Associated Herpesvirus Infection among Blood Donors from Texas JACQUES BAILLARGEON, PhD,* JIAN-HONG DENG, MD, MS,* EVELYN HETTLER, BS, CHANTAL HARRISON, MD, JAMES J. GRADY, DrPH, LAURA G. KORTE, BS, JAMES ALEXANDER, MD, EDUARDO MONTALVO, PhD, HAL B. JENSON, MD AND SHOU-JIANG GAO, PhD , PURPOSE: Kaposi’s sarcoma-associated herpesvirus (KSHV), a gammaherpesvirus recently discovered among AIDS patients with Kaposi’s sarcoma, is a potential candidate for screening in blood and plasma donors. While a number of studies have assessed KSHV infection among U.S. blood donors, larger-scale population-based studies would be necessary to develop more refined estimates of the magnitude and vari- ation of KSHV infection across different geographic regions of the U.S. blood supply. The goal of the present study, therefore, was to determine the seroprevalence of KSHV infection and to assess demo- graphic correlates of KSHV infection among south Texas blood donors. METHODS: KSHV infection was determined using specific serologic assays that measure antibodies to KSHV latent and lytic antigens. RESULTS: The overall seroprevalence of KSHV in Texas blood donors (15.0%) is substantially higher than previously reported among blood donor and general population samples in the United States. This high rate of KSHV infection persisted across most of the sociodemographic subgroups under study but was particularly elevated among participants with less than a high school education. The infection rate also in- creased linearly with age. CONCLUSIONS: The elevated infection rate reported in the present study suggests that screening methods to detect KSHV infection in blood donors should be considered. In view of the etiologic role of KSHV for several malignancies, it would be important for future studies to directly assess the risk of KSHV transmission via blood transfusion. Ann Epidemiol 2001;11:512–518. © 2001 Elsevier Science Inc. All rights reserved. KEY WORDS: Blood Donors, KSHV, KS, Seroprevalence. donors (1, 2). Although no universal guidelines currently exist to determine whether a virus is screened in blood do- nors, most blood centers screen for viruses that meet the following four generally accepted criteria: 1. highly pathogenic, 2. persistent, 3. of low prevalence in the general population, and 4. transmissible through blood or blood products. (1) Kaposi’s sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV8), is a gammaherpes- virus initially discovered among acquired immunodefi- ciency syndrome (AIDS) patients with Kaposi’s sarcoma (KS), and a potential candidate for screening in blood and plasma donors. KSHV is etiologically associated with all clinical forms of KS (3–9), primary effusion lymphoma (10– 13), and multicentric Castleman’s disease (14–16). KSHV is closely related to herpesvirus saimiri and Epstein-Barr vi- rus (EBV) (17, 18), both of which are lymphotropic trans- forming viruses (19, 20). It also encodes several functional genes that regulate cellular apoptosis and proliferation (21– 30). KSHV is capable of transforming human primary en- From the Department of Pediatrics (J.B., J.-H.D., E.H., E.M., H.B.J., S.- J.G.), the Department of Microbiology (J.-H.D., E.H., H.B.J., S.-J.G.), and the Department of Pathology (C.H.), The University of Texas Health Sci- ence Center, San Antonio, Texas; the Department of Preventive Medi- cine and Community Health, University of Texas Medical Branch, Galveston, Texas (J.J.G.); the Gulf Coast Regional Blood Center, Hous- ton, Texas (L.G.K.); and the American Red Cross, Blood Services Texas Division, Dallas Donor Center, Dallas, Texas (J.A.). Address correspondences to: Dr. Shou-Jiang Gao, Department of Pedi- atrics, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900. Received December 20, 2000; revised March 23, 2001; accepted April 6, 2001. *J.B. and J.-H.D. contributed equally.