Control of endemic bovine Tb in New Zealand possum populations: Results from a simple model

Detailed formulae, and approximate ones based on disease reproductive rates, are derived for the rates of harvesting, sterilization and vaccination required to eliminate Tb from a possum (Trichosurus vulpecula ) population, assuming either density-dependent recruitment or density-dependent mortality, asymmetric population growth and pseudo-vertical disease transmission. The threshold density of susceptible possums for disease elimination is about half the uncontrolled population density, achieved by harvesting or sterilizing an annual proportion of the population approximately equal to r (0 multiplied by 2-0 multiplied by 3) or immunizing an approximate annual proportion 3r/2. The required immunization rate for disease elimination is highly sensitive to the nature of host density dependence.

Author N. D. Barlow
Year 1991
Secondary title Journal of Applied Ecology
Volume 28
Number 3
Pages 794-809