Population Biology of Multihost Pathogens
Abstract
The majority of pathogens, including many of medical and veterinary importance, can infect more than one species of host. Population biology has yet to explain why perceived evolutionary advantages of pathogen specialization are, in practice, outweighed by those of generalization. Factors that predispose pathogens to generalism include high levels of genetic diversity and abundant opportunities for cross-species transmission, and the taxonomic distributions of generalists and specialists appear to reflect these factors. Generalism also has consequences for the evolution of virulence and for pathogen epidemiology, making both much less predictable. The evolutionary advantages and disadvantages of generalism are so finely balanced that even closely related pathogens can have very different host range sizes.
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We gratefully acknowledge colleagues at the Centre for Tropical Veterinary Medicine for valuable discussions, and the Wellcome Trust for financial support.
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Volume 292 | Issue 5519
11 May 2001
11 May 2001
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Published in print: 11 May 2001
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- Mark E. J. Woolhouse et al.
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