BACKGROUND: Hepatitis D virus (HDV) is a degenerate RNA virus or virusoid that requires the surface coat of hepatitis B virus (HBV), i.e. hepatitis B surface antigen (HBsAg), in order to become infectious. Three distinct genotypes of the virus have been classified. In this study, HDV genotypes were determined by restriction fragment length polymorphism (RFLP) and direct sequencing. In Thailand, simultaneous HDV/HBV infections are particularly prevalent among intravenous drug users (IVDU). PATIENTS AND METHODS: A total of 743 IVDU sera were screened for HBV infection. HBsAg-positive samples were subjected to serological analysis for anti-HDV. RFLP analysis using the endonucleases Xho I and Sma I was performed on the PCR amplified HDV genome to establish the prevailing HDV genotypes. RESULTS: 55 sera (7%) had detectable HBsAg; all 55 were subsequently subjected to serological analysis for anti-HDV, 12 (21.8%) of which were positive. Eight (66%) specimens had detectable HDV-RNA by RT-PCR. All polymorphisms were shown to be genotype I, a finding confirmed by direct sequencing. 36 HBsAg-positive sera obtained from the blood bank to serve as controls were negative for anti-HDV. CONCLUSION: Our data show that HDV infection is still limited among IVDU and that the pattern of polymorphism closely resembles that of the western HDV genotype I.
BACKGROUND: Hepatitis D virus (HDV) is a degenerate RNA virus or virusoid that requires the surface coat of hepatitis B virus (HBV), i.e. hepatitis B surface antigen (HBsAg), in order to become infectious. Three distinct genotypes of the virus have been classified. In this study, HDV genotypes were determined by restriction fragment length polymorphism (RFLP) and direct sequencing. In Thailand, simultaneous HDV/HBV infections are particularly prevalent among intravenous drug users (IVDU). PATIENTS AND METHODS: A total of 743 IVDU sera were screened for HBV infection. HBsAg-positive samples were subjected to serological analysis for anti-HDV. RFLP analysis using the endonucleases Xho I and Sma I was performed on the PCR amplified HDV genome to establish the prevailing HDV genotypes. RESULTS: 55 sera (7%) had detectable HBsAg; all 55 were subsequently subjected to serological analysis for anti-HDV, 12 (21.8%) of which were positive. Eight (66%) specimens had detectable HDV-RNA by RT-PCR. All polymorphisms were shown to be genotype I, a finding confirmed by direct sequencing. 36 HBsAg-positive sera obtained from the blood bank to serve as controls were negative for anti-HDV. CONCLUSION: Our data show that HDV infection is still limited among IVDU and that the pattern of polymorphism closely resembles that of the western HDV genotype I.
Authors: Bui Tien Sy; Boris A Ratsch; Nguyen Linh Toan; Le Huu Song; Christian Wollboldt; Agnes Bryniok; Hung Minh Nguyen; Hoang Van Luong; Thirumalaisamy P Velavan; Heiner Wedemeyer; Peter G Kremsner; C-Thomas Bock Journal: PLoS One Date: 2013-10-18 Impact factor: 3.240