title: Characterization of the occult hepatitis B virus variants circulating among the blood donors from eastern India.
abstract: A previous study from West Bengal documented very high rate of occult HBV infection (OBI) among the HBsAg negative blood donors. This study was aimed to characterize the OBI strains circulating among the blood donors and to estimate the risk associated with the prevailing viral variants/mutants. Blood samples from 2195 voluntary blood donors were included in the study. HBsAg, HBeAg, anti-HBc, and anti-HBs statuses of the samples were done by ELISA based detection. PCR amplification and sequencing were done to determine HBV genotypes, basal core promoter (BCP), and precore (Pre-C) mutations. Among the study samples, 268 were anti-HBc positive/HBsAg negative, among which 65 (24.25%) were HBV DNA positive. Phylogenetic analysis revealed the presence of HBV/D (87.23%), HBV/A (8.51%), and HBV/C (4.26%) (P < 0.0001). HBV/D3 (65.85%) was the significantly prevalent subgenotype over HBV/D2 (26.83%) and HBV/D1 (7.31%) (P = 0.0003). Considerable prevalence of differential BCP (1752C, 1753C, 1762T/1764A, 1753C+1762T/1764A, 1773C, and 1814C) and reverse transcriptase (rt) gene (rtI91L, rtL93P, rtS106C, rtR110G, rtN118T, rtS119T, rtY126H, rtG127W/R, rtC136R, and rtY158H) mutations was identified. Association of specific HBV subgenotypes with OBI was interesting and needs further study. Clinically relevant mutations were prevalent among the OBI strains which are of serious concern.
authors.affiliation: ICMR Virus Unit, Kolkata, GB 4, 1st Floor, ID & BG Hospital Campus, 57 Dr. Suresh Chandra Banerjee Road, Kolkata 700010, India.
authors.forename: Avik
authors.initials: A
authors.lastname: Biswas
authors.forename: Rajesh
authors.initials: R
authors.lastname: Panigrahi
authors.forename: Partha Kumar
authors.initials: PK
authors.lastname: Chandra
authors.forename: Arup
authors.initials: A
authors.lastname: Banerjee
authors.forename: Sibnarayan
authors.initials: S
authors.lastname: Datta
authors.forename: Manisha
authors.initials: M
authors.lastname: Pal
authors.forename: Subhashish
authors.initials: S
authors.lastname: Chakraborty
authors.forename: Prasun
authors.initials: P
authors.lastname: Bhattacharya
authors.forename: Sekhar
authors.initials: S
authors.lastname: Chakrabarti
authors.forename: Runu
authors.initials: R
authors.lastname: Chakravarty
mesh_terms: D000328:Adult; D001782:Blood Donors; D006509:Hepatitis B / Q000276:immunology / Q000821:virology*; D006510:Hepatitis B Antibodies / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007194:India; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D011401:Promoter Regions, Genetic
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens