Badger vaccination may not be enough to eradicate bovine TB, new research from Wageningen University and UCD has suggested.

Research by You Chang, funded by the Department of Agriculture’s Bovine TB Eradication Programme, and based on trials in Co Kilkenny, shows that Ireland’s target of eradicating TB will require a multi-pronged approach.

It would need to target TB transmission between cattle, and between cattle and badgers, as well as movement restrictions in addition to the current test and remove policy in place.

For individual cattle, other cattle are the biggest source of infection (47%-63%), while badgers are the source of infection for 30-41%, and cattle movements account for 6-12% of infection.

However, on a herd basis, multiple sources of infection contribute to herd breakdowns.

Published in the international Journal of Preventive Veterinary Medicine, veterinary epidemiologist Chang wrote: “Our results show that cattle-to-cattle transmission contributes most to new cattle infections at the individual animal (cattle) level, while breakdowns at the herd level usually involve multiple routes.

“Badger vaccination, when combined with cattle test-and-removal programme, may not be sufficient to achieve eradication in this region.”

She added: “We highlight the need for additional interventions that target cattle, badger, and movement to form a comprehensive intervention strategy, including cattle vaccination, improve farm biosecurity, badger vaccination and risk-based trading.”