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Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
Published on: May 2, 2018
Multiple infections and the evolution of virulence
Samuel Alizon1, Jacobus C de Roode, Yannis Michalakis
1Laboratoire MIVEGEC (UMR CNRS 5290, UR IRD 224, UM1, UM2), Montpellier, France. samuel.alizon@montp.cnrs.fr
Ecology Letters
|January 26, 2013
Summary
Mixed parasite infections are common and impact disease evolution. Within-host parasite interactions significantly influence virulence evolution, supported by experimental data, offering insights into complex infections.
Area of Science:
- Evolutionary biology
- Parasitology
- Public health
Background:
- Multiple parasite infections (mixed infections) are prevalent in natural populations.
- These infections are theoretically important for understanding infectious disease and virulence evolution.
- Empirical evidence for the theoretical predictions regarding mixed infections and virulence evolution is limited.
Purpose of the Study:
- To synthesize theoretical predictions and empirical evidence on how within-host parasite interactions shape virulence evolution.
- To explore the challenges and limitations in experimentally studying mixed infections and their evolutionary outcomes.
- To discuss the distinctions between coinfections involving different strains versus different species of parasites.
Main Methods:
- Review and synthesis of existing theoretical models and experimental data on mixed infections.
- Analysis of how within-host parasite interactions influence evolutionary trajectories of virulence.
- Discussion of experimental approaches and their limitations in studying evolutionary dynamics of mixed infections.
Main Results:
- Experimental data largely support theoretical predictions that within-host parasite interactions are key drivers of virulence evolution.
- Coinfections involving different strains of the same species may have different evolutionary consequences compared to coinfections with different species.
- A significant limitation is drawing evolutionary conclusions from studies focused on individual-level outcomes.
Conclusions:
- Within-host interactions among multiple parasites are critical for understanding virulence evolution.
- Experimental evolution settings offer a promising avenue for unraveling the complexities of mixed infections and their impact on virulence.
- Despite complexity, a coherent understanding of virulence evolution in mixed infections is achievable.
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