Host-pathogen system Empirical observations Model supported Reference Humans-measles Humans-pertussis Humans-diphtheria Humans-scarlet fever Found
to be relatively invariant across population sizes. Frequency dependent [15 ] Humans-smallpox Transmission was inverse of population size Frequency dependent [58 ] House finches-mycoplasma Transmission was independent of flock sizes Frequency dependent [59 ] Pigs-Aujeszky’s disease virus (ADV)
was invariant across different population sizesFrequency dependent [21 ] Harbor seals-phocine distemper virus (PDV) Density-dependent scaling did not explain differences in transmission between different-sized seal haul-out sites Frequency dependent [20 ] Rana mucosa-chytridiomycosis Transmission rate increases and saturates with density of infected individuals Frequency dependent [33 ] Tasmanian devil—devil facial tumor disease Maintenance of high prevalence following population decline Frequency dependent [34 ] Brushtail possums-leptospira interogans Density-dependent model fit experimental infection rates Density dependent [60 ] Elk-brucellosis Population density was associated with an increase in seroprevalence but could not differentiate among linear and nonlinear effects of host density. Nonlinear Density dependent [61 ] Rodents-cowpox Both models fit to incidence time series; support for both equivocal. Frequency and density dependent [22 ] Rodents-cowpox Transmission term lies between density- and frequency-dependent and varies seasonally. Model is intermediate [11 ] Indian meal moth-granulosis virus A decline in transmission with increasing density of infectious cadavers Neither [26 ] Possum-tuberculosis Transmission did not fit frequency- or density-dependent models Neither [62 ] Tiger salamander-Abystomatigrinum virus Transmission was best modeled by a power or negative binomial function, that is, nonlinear density dependence. Neither [63 ] Badgers-Mycobacterium bovis Negative relationship between host abundance and infection prevalence Neither [64 ]