title: Molecular epidemiology of hepatitis B and Delta virus strains that spread in the Mediterranean North East Coast of Tunisia.
abstract: BACKGROUND
  Tunisia is classified as an area of middle endemic for hepatitis B virus (HBV) infection, however little is known about hepatitis Delta virus (HDV) infection.
  
  
  OBJECTIVE
  This study aimed to address the prevalence of HDV infection, to identify possible risks factors, and to analyze the genetic diversity of HDV strains that are spreading in Tunisia.
  
  
  METHODS
  A retrospective large-scale study including 1615 HBsAg positive patients, native of the North East coast of Tunisia, recruited from Gastroenterology departments, was conducted. Demographic, epidemiological, ethnical, clinical and biological data were recorded. HBV and HDV serological analyses and DNA and RNA viral load quantification were performed. Genotyping of HBV and HDV strains was performed using nucleotide sequencing followed by phylogenetic analyses.
  
  
  RESULTS
  The study population included 819 (50.7%) men and 796 (49.3%) women; aged 12-90 years (mean age 41±13 years). A very low prevalence of HDV infection, 2% was observed. No risk factor, except a history of hospitalization for surgery was found. All HDV strains belonged to genotype 1, with a wide distribution within the HDV-1 group. They all share the African amino acid marker, a serine at position 202 of the large Delta protein. HBV genotypes were distributed as follows: HBV/D1 (56.8%), HBV/D7 (40.9%), and HBV/A2 (2.3%).
  
  
  CONCLUSIONS
  Tunisia is a low endemic region for HDV infection, due to an efficient policy of HBV infection control. HDV-1 is the sole genotype found, with a high diversity within this group. Further studies are ongoing in order to better characterize and manage the HBV/HDV-infected patients according to the genetic variability of the viral strains.
authors.affiliation: Laboratoire de Virologie Clinique, Institut Pasteur de Tunis, Tunisia; Carthage University, Tunis, Tunisia.
authors.forename: Lamia
authors.initials: L
authors.lastname: Yacoubi
authors.affiliation: Laboratoire de Bactériologie, Virologie, Hygiène, Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, Laboratoire Associé au Centre National de Référence des Hépatites B, C et Delta, UFR Santé Médecine Biologie Humaine, Université Paris 13, Bobigny, France.
authors.forename: Ségolène
authors.initials: S
authors.lastname: Brichler
authors.affiliation: Laboratoire de Bactériologie, Virologie, Hygiène, Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, Laboratoire Associé au Centre National de Référence des Hépatites B, C et Delta, UFR Santé Médecine Biologie Humaine, Université Paris 13, Bobigny, France.
authors.forename: Wael
authors.initials: W
authors.lastname: Mansour
authors.affiliation: Laboratoire de Bactériologie, Virologie, Hygiène, Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, Laboratoire Associé au Centre National de Référence des Hépatites B, C et Delta, UFR Santé Médecine Biologie Humaine, Université Paris 13, Bobigny, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Le Gal
authors.affiliation: Laboratoire de Virologie Clinique, Institut Pasteur de Tunis, Tunisia.
authors.forename: Walid
authors.initials: W
authors.lastname: Hammami
authors.affiliation: Laboratoire de Virologie Clinique, Institut Pasteur de Tunis, Tunisia.
authors.forename: Amel
authors.initials: A
authors.lastname: Sadraoui
authors.affiliation: Department of Gastroenterology B, La Rabta Hospital, Tunisia; Tunis El Manar University, Tunis, Tunisia.
authors.forename: Nabil
authors.initials: N
authors.lastname: Ben Mami
authors.affiliation: Department of Gastroenterology, Tahar Maamouri Hospital, Nabeul, Tunisia; Tunis El Manar University, Tunis, Tunisia.
authors.forename: Azouz
authors.initials: A
authors.lastname: Msaddek
authors.affiliation: Department of Gastroenterology, Habib Bougatfa Hospital, Bizerte, Tunisia; Tunis El Manar University, Tunis, Tunisia.
authors.forename: Imed
authors.initials: I
authors.lastname: Cheikh
authors.affiliation: Laboratoire de Virologie Clinique, Institut Pasteur de Tunis, Tunisia; Tunis El Manar University, Tunis, Tunisia. Electronic address: henda.triki@pasteur.rns.tn.
authors.forename: Henda
authors.initials: H
authors.lastname: Triki
authors.affiliation: Laboratoire de Bactériologie, Virologie, Hygiène, Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, Laboratoire Associé au Centre National de Référence des Hépatites B, C et Delta, UFR Santé Médecine Biologie Humaine, Université Paris 13, Bobigny, France. Electronic address: emmanuel.gordien@aphp.fr.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Gordien
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004279:DNA, Viral / Q000097:blood; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006509:Hepatitis B / Q000453:epidemiology* / Q000821:virology; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D003699:Hepatitis D / Q000453:epidemiology* / Q000821:virology; D003698:Hepatitis Delta Virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D019083:Mediterranean Region; D008875:Middle Aged; D010802:Phylogeny; D015995:Prevalence; D012367:RNA, Viral / Q000097:blood; D012189:Retrospective Studies; D012307:Risk Factors; D017422:Sequence Analysis, DNA; D014416:Tunisia / Q000453:epidemiology; D019562:Viral Load; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral
keywords: Genotypes; HBV; HDV; Seroprevalence