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Updated: May 2, 2026
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Quantifying Human Norovirus Virus-like Particles Binding to Commensal Bacteria Using Flow Cytometry
Published on: April 29, 2020
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Within-host evolution results in antigenically distinct GII.4 noroviruses
Kari Debbink1, Lisa C Lindesmith2, Martin T Ferris3
1Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, North Carolina, USA.
Journal of Virology
|March 21, 2014
Summary
Chronic norovirus infections in immunocompromised individuals can lead to the emergence of new, antigenically distinct strains. This evolution may enable viruses to escape herd immunity, potentially driving future outbreaks.
Area of Science:
- Virology
- Immunology
- Molecular Evolution
Background:
- Genogroup II, genotype 4 (GII.4) noroviruses rapidly evolve, with new strains emerging every 2-4 years.
- Chronically infected immunocompromised individuals are hypothesized reservoirs for novel GII.4 strains due to higher viral genetic diversity.
- The relationship between genetic variation and antigenic variation in noroviruses is not well understood.
Purpose of the Study:
- To investigate the antigenic evolution of GII.4 noroviruses during chronic infection.
- To determine if intrahost evolution can produce strains antigenically distinct from epidemic strains.
- To assess the potential of chronically infected individuals as sources for new norovirus outbreak strains.
Main Methods:
- Synthetic reconstruction of virus-like particles (VLPs) from early and late isolates of GII.4 norovirus from a chronically infected patient.
- Comparison of antigenic properties of reconstructed VLPs with parental and previously predominant GII.4 strains.
- Analysis of viral genetic variation and its correlation with antigenic changes.
Main Results:
- Intrahost evolution of GII.4 norovirus resulted in antigenically distinct strains over time.
- The observed antigenic variation during chronic infection was comparable to that between successive epidemic GII.4 strains (e.g., GII.4-2006b and GII.4-2009).
- Specific capsid protein residues showed patterned changes, suggesting positive selection.
Conclusions:
- Chronic norovirus infections can drive viral evolution, leading to the emergence of antigenically novel strains.
- These evolved strains may possess the ability to escape existing herd immunity, contributing to new outbreaks.
- Immunocompromised individuals with chronic norovirus infections represent a significant reservoir for the evolution of epidemic GII.4 strains.
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