title: Prevalence of, and risk factors for Kaposi's sarcoma-associated herpesvirus infection among blood donors in Brazil: a multi-center serosurvey.
abstract: Kaposi's sarcoma-associated herpesvirus (KSHV) is endemic in the Amazon and rare in southern regions of Brazil. However, geographical distribution and epidemiological correlates of infection in this large country are still poorly defined. To estimate the seroprevalence of, and risk factors for, KSHV infection in Brazil, a multi-center study was conducted among 3,493 first-time voluntary unpaid blood donors from Salvador, Sao Paulo and Manaus. Antibodies against KSHV were detected using a whole-virus ELISA validated prior to the serosurvey. Antibodies against the latency-associated nuclear antigen (LANA) were detected by immuno-fluorescence assay (IFA) among ELISA-positive sera and a random sample of ELISA-negative sera. Overall, seroprevalence of KSHV by whole-virus ELISA was 21.7% (95% confidence interval (CI): 20-23.4%) in men and 31.7% (95% CI: 29-34.3%) in women (P<0.0001). KSHV antibodies were detected by IFA-LANA in 3% (95% CI: 2-4.3%) of 867 ELISA-positive samples and in none of 365 randomly selected ELISA-negative samples. In multivariate analysis, KSHV seroprevalence by whole-virus ELISA was independently associated with female sex (odds ratio [OR]=1.6, 95% CI: 1.4-1.9); residence in the Amazon (OR=1.4, 95% CI: 1.2-1.8; compared to Salvador); Caucasian ethnicity (OR=1.3, 95% CI: 1.1-1.6) and herpes simplex virus type 2 (HSV-2) infection (OR=1.3, 95% CI: 1.1-1.6). KSHV seroprevalence did not significantly increase with age, nor was it associated with self-reported sexual behavior. KSHV seroprevalence is high among Brazilian blood donors, particularly from the Amazon region. This study supports the co-existence of sexual and non-sexual routes of KSHV transmission in this population.
authors.affiliation: Clinical Research Unit, Department of Infectious & Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom. maria.nascimento@lshtm.ac.uk
authors.forename: Maria Claudia
authors.initials: MC
authors.lastname: Nascimento
authors.forename: Vanda Akico
authors.initials: VA
authors.lastname: de Souza
authors.forename: Laura Masami
authors.initials: LM
authors.lastname: Sumita
authors.forename: Wilton
authors.initials: W
authors.lastname: Freire
authors.forename: Helen A
authors.initials: HA
authors.lastname: Weiss
authors.forename: Ester C
authors.initials: EC
authors.lastname: Sabino
authors.forename: Silvia
authors.initials: S
authors.lastname: Franceschi
authors.forename: Claudio Sergio
authors.initials: CS
authors.lastname: Pannuti
authors.forename: Philippe
authors.initials: P
authors.lastname: Mayaud
mesh_terms: D000293:Adolescent; D000328:Adult; D001782:Blood Donors; D001938:Brazil / Q000453:epidemiology; D005260:Female; D019288:Herpesvirus 8, Human / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012514:Sarcoma, Kaposi / Q000453:epidemiology* / Q000209:etiology / Q000821:virology