Research from the Universities of Bristol and Cambridge has found that targeting badger-to-badger BTB transmission is less effective than targeting badger-to-cattle and cattle-to-cattle transmission. The research, which was funded by the Engineering and Physical Sciences Research Council, found that Bovine Tuberculosis (BTB) is most likely to be nearly under control in cattle and badgers as separate species taken in isolation. Together, however, control is likely to be considerably more challenging.
Using mathematical modelling techniques combined with data from a range of sources, including badger and cattle population data and BTB infection rates, researchers from Bristol’s School of Social and Community Medicine and Cambridge’s Department of Veterinary Medicine, were able to model the cycle of infection between cattle and badgers and predict the impact of BTB controls.
The findings showed that while infection in both cattle and badgers is most likely nearly under control on their own, targeting badger-to-badger transmission has only had a modest impact on cattle infection. More effective strategies are reducing badger-to-cattle and cattle-to-cattle transmission.
Dr Ellen Brooks-Pollock, the study’s lead author and now lecturer in Infectious Disease Mathematical Modelling at the University of Bristol, said the findings have particular implications for badger vaccination programmes, depending on local incidence of badger infection.
“Bovine TB has had a serious impact on the cattle industry in the UK, as well as across Europe. Our findings show that in areas with badger infection, cattle-to-badger and badger-to-cattle transmission is critical to the whole system. You can’t just consider one species in isolation. Reducing badger-to-cattle transmission is likely to be more effective than reducing prevalence in badgers alone.”
Just last week Irish Minister for Agriculture, Simon Coveney, said he was confident that culling can be replaced by a badger vaccination programme in due course and that the sooner it could be introduced the better. On a precautionary note the minister added that the replacement needs to be done on the basis of science.
In contrast to the Bristol and Cambridge study, research carried out recently by the Agri-Food and Biosciences Institute (AFBI) in Northern Ireland has suggested that it is unlikely that direct contact between badgers and cattle is a major factor in the spread of the disease.
However, Dr Declan O’Mahony of the AFBI, who led the study, added the caveat that “whilst direct interactions between cattle and badgers were not recorded in this study, that does of course not necessarily mean that interactions do not occur. It does support the increasing evidence that such contact is likely to be at a very low level, but still may be important if infected animals are involved.”
(Source – Irish Farmers Journal – 18/05/2015)