Premium
The ecology of virulence
Author(s) -
Lively Curtis M.
Publication year - 2006
Publication title -
ecology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.852
H-Index - 265
eISSN - 1461-0248
pISSN - 1461-023X
DOI - 10.1111/j.1461-0248.2006.00969.x
Subject(s) - ecology , virulence , biology , applied ecology , geography , biodiversity , gene , biochemistry
Theoretical work has shown that parasites should evolve intermediate levels of virulence. Less attention has been given to the ecology of virulence. Here I explore population‐dynamic models of infection in an annual host. The infection does not kill the host; but it can decrease the number of offspring produced by the host, and the magnitude of this effect depends on host population size. Hence, ‘virulence’ is density dependent, and is defined here as the difference in birth rates between uninfected and infected hosts, divided by the birth rate of uninfected hosts. The results suggest that infection can be highly virulent at the host's equilibrium density, even though the parasite has no effect on the host's intrinsic birth rate. The results also suggest that parasites may help to stabilize host population dynamics. In general, the impact of infection may be underestimated in natural populations.