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Updated: Jul 12, 2025
07:02
Quantifying Human Norovirus Virus-like Particles Binding to Commensal Bacteria Using Flow Cytometry
Published on: April 29, 2020
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Norovirus evolves as one or more distinct clonal populations in immunocompromised hosts
Natthawan Chaimongkol1, Nathânia Dábilla1,2, Kentaro Tohma3
1Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
Mbio
|October 31, 2023
Summary
Noroviruses cause chronic diarrhea in immunocompromised individuals. This study reveals diverse norovirus strains can persist, with some patients shedding co-evolving viral populations.
Area of Science:
- Virology
- Immunology
- Gastroenterology
Background:
- Noroviruses are a significant cause of chronic diarrhea in immunocompromised patients.
- Current therapies are ineffective at clearing persistent norovirus infections, which can last for years.
Purpose of the Study:
- To investigate the genetic diversity of norovirus strains associated with chronic infections in immunocompromised individuals.
- To understand the mechanisms of viral persistence and adaptation during long-term norovirus shedding.
Main Methods:
- High-resolution next-generation sequencing was used to analyze near full-length norovirus genomes.
- Genetic data from a cohort of immunocompromised patients with chronic norovirus infection were analyzed.
- Analysis focused on identifying distinct viral populations and their evolutionary dynamics.
Main Results:
- A remarkable diversity of norovirus strains was observed in the studied patient cohort.
- Most, if not all, circulating noroviruses may have the potential to establish chronic infections in immunocompromised individuals.
- Certain patients shed noroviruses divisible into distinct, independently co-evolving haplotypes.
Conclusions:
- Understanding norovirus haplotypes is crucial for comprehending viral adaptation and persistence in chronic infections.
- Tracking viral haplotypes can inform strategies for managing norovirus infections, especially under selective pressures like antiviral drugs.
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