Vaccinating wild badgers against bovine tuberculosis: an overview of 16 years of vaccine delivery in England.

Introduction: The European badger ( Methods: Here we provide a comprehensive overview of 16 years of badger vaccination delivery in England, summarizing national deployment trends, geographical expansion, recorded welfare-related observations, operational efficiency in government led programmes, and the effects of culling history on trapping success. Results: From 2010 to 25 there were 84,085 trap nights, resulting in 25,692 vaccine doses administered to wild badgers in England. Visual welfare assessments by lay vaccinators recorded >99% of badgers as normal for demeanor, respiration, condition, and movement. Minor injuries such as abrasions to the forelimbs were recorded in 4.2% of badgers with serious injuries extremely rare (0.03% of captures) and veterinary callouts required in only 0.04% of events. Trapping efficiency varied by month and trap location and was significantly higher in unculled populations, than those where culling had recently taken place. In post-cull areas, trapping success increased steadily with time, which may suggest partial population recovery and increasing trap encounter rates. Discussion: These results show that badger vaccination in England has expanded substantially and can be delivered across diverse landscapes, including areas recently subject to culling. While vaccination using traps is unlikely to become a landscape-wide tool due to costs and logistical constraints, it can act as a targeted intervention in areas where badgers contribute meaningfully to disease transmission. These findings provide robust operational evidence to inform policy and support the strategic deployment of badger vaccination as part of England's evolving bTB control strategy.