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Published on: March 19, 2015
The evolutionary dynamics of human influenza B virus
1Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, PA 16802, USA.
Journal of Molecular Evolution
|May 28, 2008
Summary
Influenza B virus evolution is shaped by herd immunity and reassortment, with influenza A virus potentially influencing lineage dominance. This study reveals key drivers of influenza B
Area of Science:
- Virology
- Evolutionary Biology
- Epidemiology
Background:
- Influenza B virus is less common and severe than influenza A virus in humans.
- Evolutionary dynamics and inter-virus interactions of influenza B are not well understood.
Purpose of the Study:
- To investigate the evolutionary dynamics of human influenza B virus.
- To determine the role of reassortment and interactions with influenza A virus.
Main Methods:
- Phylogenetic analysis of complete influenza B virus genomes with isolation dates.
- Comparison of phylogenetic patterns across all eight viral segments.
- Analysis of nucleotide substitution rates and selection pressures.
Main Results:
- Segment reassortment occurs sporadically in influenza B virus over a 30-year period.
- Adaptive evolution, particularly in hemagglutinin, is observed, consistent with antigenic drift.
- Influenza B virus shows lower substitution rates than influenza A virus.
Conclusions:
- Herd immunity changes and reassortment drive evolutionary changes within and between influenza B lineages (Yam88, Vic87).
- Influenza A virus interaction may be crucial for shifting dominance between influenza B lineages.
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