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Updated: Feb 4, 2026
15:03
Building a Better Mosquito: Identifying the Genes Enabling Malaria and Dengue Fever Resistance in A. gambiae and A. aegypti Mosquitoes
Published on: July 4, 2007
11.4K
Timing malaria transmission with mosquito fluctuations.
Romain Pigeault1,2, Quentin Caudron3, Antoine Nicot4
1MIVEGEC (UMR CNRS 5290) University of Montpellier Montpellier France.
Evolution Letters
|October 5, 2018
Summary
Pathogens evolve to time their transmission to match vector activity. This study shows Plasmodium parasites increase infectivity in birds during peak mosquito biting times, optimizing transmission.
Area of Science:
- Evolutionary Biology
- Parasitology
- Epidemiology
Background:
- Temporal variations in vector activity influence vector-borne pathogen epidemiology and evolution.
- The
- Hawking hypothesis
- proposes pathogens evolve to time transmission with vector activity.
Purpose of the Study:
- To identify conditions favoring evolution of time-varying pathogen transmission strategies.
- To experimentally test the
- Hawking hypothesis
- using Plasmodium relictum in birds.
Main Methods:
- Theoretical modeling to determine conditions for time-varying transmission.
- Experimental monitoring of Plasmodium relictum within-host dynamics.
- Assessing parasitemia and mosquito infection correlating with vector biting times.
Main Results:
- Periodic increases in parasitemia and mosquito infection detected in the late afternoon.
- Increased Plasmodium replication observed following mosquito bites in both acute and chronic infection phases.
- Plasmodium parasites employ distinct strategies to synchronize transmission with vector availability.
Conclusions:
- Plasmodium parasites exhibit adaptive, time-varying transmission strategies, both unconditional and plastic.
- These strategies enhance the match between parasite transmission potential and vector activity patterns.
- Findings support the adaptive nature of pathogen strategies in response to predictable vector activity fluctuations.
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