Molecular genotyping of duck hepatitis A viruses (DHAV) in Vietnam
Introduction: The aim of this study was to identify the genetic characteristics and molecular genotyping of duck hepatitis A virus (DHAV) isolated in Vietnam during 2009–2013.
Methodology: Thirty duckling livers from outbreaks between 2009 and 2013 in seven provinces were collected and identified by polymerase chain reaction (PCR). Then, VP1 genes of eleven positive samples and two attenuated vaccine strains were sequenced and analyzed.
Results: Genotypic and phylogenetic analyses indicated that the 13 Vietnamese isolates were classified into two genotypes, DHAV-1 and DHAV-3. The rate of identity and homology was 91%–100% between the 10 Vietnamese and 26 global strains of DHAV-3, and 92%–100% between 3 Vietnamese and 16 strains of DHAV-1. Between the DHAV-3 and DHAV-1 strains, the divergence reached 30%. At the C-terminal of VP1 for the different strains, a hypervariable region was observed, and notably, six of the Vietnamese DHAV-3 strains in this study showed four consistent differences (at positions T184M, Q200H, K207N, and K214R) within this group that were distinct from all other DHAV-3 strains.
Conclusions: This is the first report of molecular characterization of DHAVs in Vietnam. At least two genotypes were identified, DHAV-1 and DHAV-3, with diversified clades within and between genotypes. DHAV-3 seemed to be dominant in Vietnam.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).