title: Molecular and serological characterization of occult hepatitis B infection in blood donors from Mexico.
abstract: Occult hepatitis B virus (HBV) infection (OBI) is characterized by presence of HBV DNA in blood or liver tissue without detectable HBV surface antigen (HBsAg), with or without antibodies to hepatitis B core antigen (anti-HBc) or antibodies against HBsAg (anti-HBs). A molecular and serological characterization was done of OBI in blood donors from Yucatan, Mexico. HBV DNA was found in 24 (6.4%) of the 372 evaluated samples. Anti-HBs was present in 15/24 samples (62.5%), and no significant difference was observed between HBV DNA positivity and anti-HBs levels. HBV genotype H was detected in 66.7% of samples, followed by genotypes D (20.8%) and F (8.3%). Amino acid substitutions were identified in the core region of nine samples, and most of these changes were located in immunodominant epitopes. No precore stop codon 28 mutant (W28Stop) was identified among the analyzed HBV isolates. In conclusion, genotype H is the main circulating HBV strain among OBI blood donors from Yucatan, Mexico. Mutations in the core region may contribute to viral persistence.
authors.affiliation: Centro Médico Nacional Ignacio García Téllez, Instituto Mexicano del Seguro Social, Mérida, Yucatán, Mexico. bgarciam04@yahoo.com.mx
authors.forename: Beatriz María
authors.initials: BM
authors.lastname: García-Montalvo
authors.forename: Laura Patricia
authors.initials: LP
authors.lastname: Ventura-Zapata
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics; D058070:Asymptomatic Diseases / Q000453:epidemiology; D001782:Blood Donors / Q000706:statistics & numerical data*; D018388:Codon, Terminator / Q000235:genetics; D004279:DNA, Viral / Q000378:metabolism; D005260:Female; D005838:Genotype; D006512:Hepatitis B Core Antigens / Q000235:genetics*; D006515:Hepatitis B virus / Q000235:genetics* / Q000302:isolation & purification*; D019694:Hepatitis B, Chronic / Q000097:blood / Q000453:epidemiology / Q000821:virology; D006801:Humans; D016056:Immunodominant Epitopes / Q000235:genetics; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D016036:Seroepidemiologic Studies
chemical_list: D018388:Codon, Terminator; D004279:DNA, Viral; D006512:Hepatitis B Core Antigens; D016056:Immunodominant Epitopes