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Published on: May 31, 2020
Transmission-virulence trade-offs in vector-borne diseases
Samuel Alizon1, Minus van Baalen
1Ecole normale supérieure, UMR 7625 Fonctionnement et Evolution des Systèmes Ecologiques, Paris, F-75005, France. samuel@mast.queensu.ca
Theoretical Population Biology
|May 30, 2008
Summary
This study models vector-borne parasite transmission, revealing an S-shaped transmission function and a less sensitive virulence-transmission trade-off compared to direct transmission. Parasite life-cycle stages significantly impact epidemiology and treatment strategies.
Area of Science:
- Epidemiology
- Parasitology
- Mathematical Modeling
Background:
- The assumed trade-off between parasite virulence and transmission is poorly understood.
- Vector-borne parasites, like those causing malaria, present a unique model for studying this relationship due to complex life cycles.
Purpose of the Study:
- To analyze an embedded model of vector-borne parasites to understand how life-cycle aspects influence the virulence-transmission trade-off.
- To investigate the epidemiological implications of different parasite traits and treatment strategies.
Main Methods:
- Development and analysis of a mathematical model for vector-borne parasites.
- Exploration of the transmission function's shape and its sensitivity to parameter changes.
- Comparison of treatment effects on different parasite life stages.
Main Results:
- The transmission function for vector-borne parasites may exhibit an S-shape.
- The virulence-transmission trade-off is less sensitive to parameter variations than in directly transmitted diseases.
- Parasite traits, such as stage conversion, have significant epidemiological consequences.
Conclusions:
- Life-cycle characteristics critically shape the virulence-transmission dynamics of vector-borne parasites.
- Targeting specific parasite life stages (asexual vs. sexual) can have differential epidemiological impacts.
- The model provides insights into optimizing control strategies for vector-borne diseases.
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