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Updated: Aug 13, 2026
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Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Natural selection and dynamical coexistence of defective and complementing virus segments
1Laboratory of Mathematical Biology, MRC National Institute for Medical Research, Mill Hill, London, U.K.
Journal of Theoretical Biology
|August 7, 1992
Summary
Defective interfering (DI) particles and covirus segments can stably coexist with wildtype viruses. A novel structured deme model explains this viral dynamics, revealing conditions for segment coexistence.
Area of Science:
- Virology
- Mathematical Biology
- Population Dynamics
Background:
- Defective interfering (DI) particles and covirus segments coexist with wildtype viruses at high multiplicities of infection.
- DI particles act as parasites, while covirus segments are mutualists, necessitating complex models for stable coexistence.
- Within-cell reproductive advantage for viral segments is a common phenomenon.
Purpose of the Study:
- To develop a non-trivial model for the stable dynamical coexistence of viruses and their segments.
- To investigate the coexistence of virus-DI particle, virus-DI particle-resistant virus, covirus pair, and virus-covirus systems.
- To apply the structured deme model to understand virus dynamics.
Main Methods:
- Application of the structured deme model to virus dynamics.
- Modeling biochemical interactions within coinfection groups (cells).
- Assuming complete mixing of viral types between infection cycles.
Main Results:
- Analytic results were obtained for the coexistence of various virus-segment combinations.
- The model provides insights into the conditions enabling stable coexistence.
- Demonstrated the applicability of the structured deme model to complex viral populations.
Conclusions:
- The structured deme model offers a robust framework for analyzing viral coexistence dynamics.
- The model successfully predicts coexistence scenarios for DI particles and covirus segments.
- This approach advances our understanding of viral population stability and evolution.
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