Predominance of HBV Genotype B and HDV Genotype 1 in Vietnamese Patients with Chronic Hepatitis

Abstract

Hepatitis delta virus (HDV) coinfection will additionally aggravate the hepatitis B virus (HBV) burden in the coming decades, with an increase in HBV-related liver diseases. Between 2018 and 2019, a total of 205 HBV patients clinically characterized as chronic hepatitis B (CHB; n = 115), liver cirrhosis (LC; n = 21), and hepatocellular carcinoma (HCC; n = 69) were recruited. HBV surface antigen (HBsAg), antibodies against surface antigens (anti-HBs), and core antigens (anti-HBc) were determined by ELISA. The presence of hepatitis B viral DNA and hepatitis delta RNA was determined. Distinct HBV and HDV genotypes were phylogenetically reconstructed and vaccine escape mutations in the “a” determinant region of HBV were elucidated. All HBV patients were HbsAg positive, with 99% (n = 204) and 7% (n = 15) of them being positive for anti-HBc and anti-HBs, respectively. Anti-HBs positivity was higher among HCC (15%; n = 9) compared to CHB patients. The HBV-B genotype was predominant (65%; n = 134), followed by HBV-C (31%; n = 64), HBV-D, and HBV-G (3%; n = 7). HCC was observed frequently among young individuals with HBV-C genotypes. A low frequency (2%; n = 4) of vaccine escape mutations was observed. HBV-HDV coinfection was observed in 16% (n = 33) of patients with the predominant occurrence of the HDV-1 genotype. A significant association of genotypes with alanine aminotransferase (ALT) and aspartate aminotransferase (AST) enzyme levels was observed in HBV monoinfections. The prevalence of the HDV-1 genotype is high in Vietnam. No correlation was observed between HDV-HBV coinfections and disease progression when compared to HBV monoinfections.

Low Risk of Occult Hepatitis B Infection among Vietnamese Blood Donors

“…In the present study, in a study population of 623 HBsAg-negative blood donors from Hanoi, we found an OBI prevalence of 0.3%, which is low compared to the number of cases reported in a literature review for Asia (0.013-5.5%) [27,31]. This is noteworthy considering the fact that Vietnam is highly endemic for HBV [19,22], which is confirmed by the high seroprevalence of HBV markers found in this study. In fact, 73% of our samples tested positive for at least one HBV antibody (anti-HBs and anti-HBc), with 39% being positive for anti-HBc.…”

“…After nested PCR, amplicons were purified and sequenced. BLAST searches against the NCBI database revealed that the two OBI cases belonged to HBV genotype B, which is predominant in Vietnam [21][22][23]. A phylogenetic tree was then constructed using the sequences of the two OBI positive samples and 52 representative S/preS HBV sequences of A-H genotypes from the HBV database (HBVdb), which showed the two OBI positive samples clustering with genotype group B, consistent with the BLAST search results (Figure 3).…”

“…HBV DNA in serum samples was investigated using a nested PCR by targeting a highly conserved S/P region (332 bp) of the HBV genome as previously described [8,22]. Amplification reactions were carried out in 25 µL (1× PCR buffer, 0.2 mM dNTPs, 0.4 µM specific primer, and 1U HotStarTaq DNA Polymerase (Qiagen GmbH, Hilden, Germany).…”

“…The rate of HBV infections in the Vietnamese population has been estimated to range from 8 to 13.3% [18], in particular in rural areas and older age groups [19,20]. Furthermore, previous studies have shown that the HBV genotypes B and C are dominant and occur in 75 % and 25 % of cases, respectively [21][22][23]. Nevertheless, reliable data on the occurrence of OBI among blood donors in Vietnam are still lacking.…”

Characterization of Antigen Escape Mutations in Chronic HBV-Infected Patients in Upper Egypt

“…HBV genotyping was determined by amplification and sequencing of 332 bp of HBV S gene using nested PCR reaction as described previously. 21 , 22 Briefly, the first PCR was carried out using the primer pairs HBV-022 (sense primer) and antisense primers HBV-065 and HBV-066. The nested reaction was performed primers HBV-024 (sense primer) and antisense primers HBV-041 and HBV-064.…”