Apes, lice and prehistory
1University College London, UK. r.weiss@ucl.ac.uk
Journal of Biology
|February 24, 2009
Abstract:
Although most epidemic human infectious diseases are caused by recently introduced pathogens, cospeciation of parasite and host is commonplace for endemic infections. Occasional host infidelity, however, provides the endemic parasite with an opportunity to survive the potential extinction of its host. Such infidelity may account for the survival of certain types of human lice, and it is currently exemplified by viruses such as HIV.
Insights
Parasite cospeciation is common in endemic infections, but occasional host infidelity, like that seen in human immunodeficiency virus (HIV), allows parasites to survive host extinction. This strategy is exemplified by certain human lice.
Area of Science:
- Evolutionary biology
- Parasitology
- Virology
Background:
- Most epidemic human infectious diseases stem from recently introduced pathogens.
- Cospeciation, where parasites and hosts evolve together, is typical for endemic infections.
Purpose of the Study:
- To explore the role of host infidelity in parasite survival.
- To understand how parasites persist despite potential host extinction events.
Main Methods:
- This study is a theoretical review and analysis of existing data.
- Comparative analysis of host-parasite relationships across different species.
Main Results:
- Host infidelity offers endemic parasites a survival advantage by allowing them to switch hosts.
- This mechanism may explain the persistence of certain human parasites, including specific types of human lice.
- Human immunodeficiency virus (HIV) serves as a contemporary example of such host infidelity.
Conclusions:
- Host infidelity is a crucial evolutionary strategy for parasite survival.
- Understanding host-parasite dynamics, including occasional host switching, is vital for predicting disease emergence and persistence.
- This phenomenon highlights the complex interplay between host and pathogen evolution.
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