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Allocation to sexual versus nonsexual disease transmission.

Publication ,  Journal Article
Thrall, PH; Antonovics, J; Wilson, WG
Published in: The American naturalist
January 1998

Many diseases have both sexual and nonsexual transmission routes, and closely related diseases often differ in their degree of sexual transmission. We investigate the evolution of transmission mode as a function of host social and mating structure using a model in which disease transmission is explicitly dependent on the numbers of sexual and nonsexual contacts (which are themselves a function of population density) and per-contact infection probabilities. Most generally, and in the absence of trade-offs between the degree of sexual transmission and effects on host fecundity and mortality, nonsexual transmission is favored above the social-sexual crossover point (the host density at which the number of nonsexual contacts exceeds the number of sexual contacts), while sexual transmission is favored below this point. When changes in allocation to the two transmission modes are accompanied by changes in mortality or fecundity, both mixed and pure transmission strategies can be favored. If invading genotypes differ substantially from resident genotypes, genetic polymorphism in transmission mode is possible. The evolutionary outcomes are predictable from a knowledge of the equilibrium population sizes in relation to the social-sexual crossover point. Our results also show that predictions about dynamic outcomes, based on rates of invasion for single pathogens into healthy populations, do not adequately describe the resulting disease prevalence nor predict the subsequent evolutionary dynamics; once invasion of a pathogen has occurred, the conditions for spread of a second pathogen are themselves altered. If the host is considered as a single resource, our results show that two pathogens may coexist on a single resource if they use that resource differentially and have differential feedbacks on resource abundance; such resource feedback effects may be present in other biological systems.

Duke Scholars

Published In

The American naturalist

DOI

EISSN

1537-5323

ISSN

0003-0147

Publication Date

January 1998

Volume

151

Issue

1

Start / End Page

29 / 45

Related Subject Headings

  • Ecology
  • 31 Biological sciences
  • 06 Biological Sciences
 

Citation

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MLA
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Thrall, P. H., Antonovics, J., & Wilson, W. G. (1998). Allocation to sexual versus nonsexual disease transmission. The American Naturalist, 151(1), 29–45. https://doi.org/10.1086/286100
Thrall, P. H., J. Antonovics, and W. G. Wilson. “Allocation to sexual versus nonsexual disease transmission.The American Naturalist 151, no. 1 (January 1998): 29–45. https://doi.org/10.1086/286100.
Thrall PH, Antonovics J, Wilson WG. Allocation to sexual versus nonsexual disease transmission. The American naturalist. 1998 Jan;151(1):29–45.
Thrall, P. H., et al. “Allocation to sexual versus nonsexual disease transmission.The American Naturalist, vol. 151, no. 1, Jan. 1998, pp. 29–45. Epmc, doi:10.1086/286100.
Thrall PH, Antonovics J, Wilson WG. Allocation to sexual versus nonsexual disease transmission. The American naturalist. 1998 Jan;151(1):29–45.
Journal cover image

Published In

The American naturalist

DOI

EISSN

1537-5323

ISSN

0003-0147

Publication Date

January 1998

Volume

151

Issue

1

Start / End Page

29 / 45

Related Subject Headings

  • Ecology
  • 31 Biological sciences
  • 06 Biological Sciences