Pathogen Competition and Coexistence and the Evolution of Virulence

摘要: Competition between different strains of a micro-parasite which provide complete cross-protection and cross-immunity against each other selects for maximal basic replacement ratio if, in the absence disease, host population is exclusively limited its growth by nonlinear birth rate. For mass action incidence, principle R0 maximization can be extended to exponentially growing populations, if exponential rate small enough that disease limit growth. standard though not full extent, it populations which, without either grow or are growth-limited death rate, provided prevalence low there no immunity disease. If high, strain competition rather fatality. A would go extinct on own coexist with more virulent protecting from it, has strong vertical transmission.