MODELING THE CONTROL OF BOVINE TUBERCULOSIS IN BADGERS IN ENGLAND - CULLING AND THE RELEASE OF LACTATING FEMALES

1. A simulation model was used to evaluate the effect of different lev els of culling on six badger social groups in an attempt to reduce or eradicate TB infection from the population. Apart from fecundity, all model parameters were derived from a comprehensive study of a naturall y-infected badger population in England. 2. Badger control was simulat ed using a trap-and-cull of 80% of all badgers in either two social gr oups (localized strategy) or all six social groups (wide area strategy ). Lactating females were permitted to infect none or all of their you ng, to simulate the extremes of sow-to-cub (pseudo-vertical) transmiss ion. Trapped lactating sows were either all released or all killed. 3. Simulations where all infected badgers can be correctly diagnosed wer e also run to determine the importance of an improved live test for TB . 4. In the absence of badger control, pseudo-vertical transmission in creased the persistence and prevalence of TB in the simulated populati on. 5. A single control operation was capable of eradicating TB from t he population only if all six badger social groups were subjected to c ulling. If only infected individuals were killed, disease eradication was possible without a marked increase in population extinction. If al l individuals were killed, the increased level of disease eradication occurred as a result of an increase in population extinction. 6. Killi ng lactating sows had no effect on the medium-term prevalence (up to 2 0 years) of the disease and resulted only in a reduced persistence of TB when a wide area badger control strategy was used.