Dr. Osiowy is Chief of the Viral Hepatitis and Bloodborne Pathogens Section at the National Microbiology Laboratory (NML) in Winnipeg, Manitoba. She received her doctorate and research training in virology at the University of Calgary with post-doctoral training at Health Canada’s Bureau of Microbiology in Ottawa. At the NML she is responsible for managing serological and molecular diagnostic reference services for the five hepatitis viruses, investigating HAV and HBV outbreaks or suspected transmission events, and conducting viral hepatitis research including collaborators such as the Canadian Blood Services and the Canadian Hepatitis B Network.

Title: Next Generation Sequence (NGS) Analysis for Hepatitis B Virus (HBV) Outbreak Transmission Analysis in Manitoba

Background: Error-prone HBV replication results in higher evolutionary rates than with other DNA viruses. Rates are constrained by overlapping coding regions that can be used to investigate recent or past suspected transmission events.

Purpose: To develop a sensitive and robust sequencing method to analyze HBV quasispecies in specimens from persons involved in potential network transmissions.

Methods: NGS (Illumina) was conducted on HBV amplicons representing conserved (PreS/Pol) and variable (Core/ENHI) genomic regions for long- and short-term HBV evolution analyses, respectively. Phylogenetic analysis and quasispecies complexity tools were used.

Results: From 2016-2023, 98 acute HBV cases having sequence identity (340 bp of HBsAg, gtA2) were identified in Manitoba, suggesting a common transmission source. PreS NGS sequence had low diversity while the Core region displayed increased diversity, suggesting a greater likelihood of indirect transmission among most cases. Phylogenetic networking tools described possible transmission routes.
Conclusion: Deep sequencing will provide comprehensive analysis of HBV transmission events through use of phylogenetic and complexity tools.