title: Current hepatitis delta virus type 1 (HDV1) infections in central and eastern Turkey indicate a wide genetic diversity that is probably linked to different HDV1 origins.
abstract: Hepatitis delta virus (HDV) is a subviral pathogen of humans, a satellite of hepatitis B virus (HBV) that induces severe acute and chronic liver diseases. The genus Deltavirus consists of eight clades or genotypes, with HDV1 being ubiquitous and frequently characterized. In Turkey, HDV1 infection is highly endemic among HBsAg carriers, especially in the southeastern region. In this study, we analyzed 34 samples from patients who were chronically infected with HBV/HDV, originating from 22 cities of rural regions in the central and eastern parts of Turkey, in order to determine the levels of viral replication and genetic diversity. HDV RNA levels ranged between 3.02 and 8.75 Log copies/mL, and HBV DNA was detected in 25 samples (73.5%), with values ranging from 2.53 to 5.30 Log copies/mL. Analysis of nucleotides 900-1280 of HDV genomes (n = 34) and full-length (n = 17) sequences indicated that all of the strains belonged to genotype HDV1. However, a high genetic diversity was observed among the isolates, with a mean full-length dissimilarity score of 13.05%. HDV sequences clustered with sequences from Western Europe (n = 11), Eastern Europe and Asia (n = 19) or Africa (n = 4). HDV1 isolates related to strains of African origin had a serine residue instead of an alanine at position 202 of the large delta protein. HBV preS1 sequences obtained for 34 isolates indicated an HBV/D genotype in all cases. Taken together, our results indicate that in Turkey, where HBV-HDV dual infection is highly endemic, both viruses have high levels of replication, and HDV strains exhibit wide genetic diversity, which might reflect ancient evolution and/or successive outbreaks.
authors.affiliation: Service de Bactériologie, Virologie-Hygiène, Hôpital Avicenne, Assistance Publique, Hôpitaux de Paris, Laboratoire associé au Centre National de Référence des Hépatites B, C et delta, Université Paris 13, Bobigny, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Le Gal
authors.forename: Selim
authors.initials: S
authors.lastname: Badur
authors.forename: Nasser Al
authors.initials: NA
authors.lastname: Hawajri
authors.forename: Filiz
authors.initials: F
authors.lastname: Akyüz
authors.forename: Sabahattin
authors.initials: S
authors.lastname: Kaymakoglu
authors.forename: Ségolène
authors.initials: S
authors.lastname: Brichler
authors.forename: Fabien
authors.initials: F
authors.lastname: Zoulim
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Gordien
authors.forename: Elyanne
authors.initials: E
authors.lastname: Gault
authors.forename: Paul
authors.initials: P
authors.lastname: Dény
mesh_terms: D000328:Adult; D000368:Aged; D016000:Cluster Analysis; D019353:Endemic Diseases; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D019694:Hepatitis B, Chronic / Q000150:complications; D019701:Hepatitis D, Chronic / Q000453:epidemiology* / Q000821:virology*; D003698:Hepatitis Delta Virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D012424:Rural Population; D017422:Sequence Analysis, DNA; D014421:Turkey / Q000453:epidemiology; D019562:Viral Load
chemical_list: D012367:RNA, Viral