A paper in People and Nature presents a 4-year badger vaccination initiative, which suggests that badger vaccination could be a “technically effective and socially acceptable component” of bovine tuberculosis (bTB) control. The authors emphasise that badger culling has been central to the bTB control policy for “decades”, with farming leaders concerned that badger vaccination is an “impractical and potentially ineffective” approach. Therefore, a wider rollout of badger vaccination would need to engage the farming community to be successful. In the recent initiative, farmers expressed enthusiasm and a desire to continue with vaccination.
An “intractable” challenge to coexistence
The paper highlights that the coexistence of people and wildlife is “especially challenging” where there is “socio-cultural conflict over alternative management approaches”. In the UK, bovine tuberculosis (bTB), caused by Mycobacterium bovis, is “one of the most intractable challenges” to human-wildlife coexistence. The disease has “substantial” effects on the farming community and can be costly for taxpayers as well as farmers. Although transmission among cattle herds causes most bTB incidents, transmission among wild badgers (Meles meles), also plays a role and undermines bTB control efforts.
Culling or vaccination?
Badger culling contributes to bTB policy but “remains a source of intense public debate”, and the government expressed an intention to scale back badger culling and increase badger vaccination efforts.
“The potential contribution of badger vaccination to bTB control depends not only on its technical effectiveness, but also on farmers’ willingness to adopt it.”
Farmers comment on a lack of empirical evidence of effectiveness and the possibility that badger vaccination could even increase bTB risks for cows. Indeed, recent workshops found that farmers who had little experience of badger vaccination viewed the approach as “impractical, expensive, and probably ineffective”. The paper authors recognise that these concerns are justified, as badger vaccination has not undergone “rigorous assessment”. However, repeated vaccination of a badger population “would be expected” to reduce prevalence based on individual- and group-level effects.
Concern about the viability of plans to expand badger vaccination includes the risk that, as cull licences expire, some farmers might consider killing badgers unlawfully. This would not only harm badger conservation and welfare, but could undermine bTB eradication efforts; small-scale, localised culling has been shown to increase cattle bTB incidence.
The study
The authors present an observational case study of badger vaccination initiated by farmers. The project took place in an area of mid-Cornwall, near the village of St Stephen, and was initiated in November 2018 when a single farmer contacted Cornwall Wildlife Trust (CWT) about badger vaccination as an alternative to a cull. At a meeting attended by around 20 farmers, many attendees expressed an informal interest in paying for badger vaccination on their land.
A follow-up meeting in January 2019 hosted scientists from the Zoological Society of London (ZSL), who presented their knowledge about badger vaccination and limits to that knowledge. They offered to monitor the epidemiological outcomes at no additional cost if farmers wished to pay for vaccination.
Between the months of May and September in 2019-2022, badger trapping was conducted annually on each participating property for two consecutive nights. Captured badgers underwent a rapid visual health check before intramuscular injection of the vaccine Bacille Calmette Guerin (BCG), with the “Sofia strain”. Badgers that had been vaccinated were temporarily marked with a fur clip and released at the point of capture. Over 4 years, 265 badger vaccinations were achieved.
“Practicable, technically effective, and acceptable”
Although the case study was small-scale, the authors infer that badger vaccination can be “practicable, technically effective, and acceptable to farmers”. The percentage of badgers that tested positive for M. bovis exposure declined from 16.0% to 0%, and participating landholders were “happy” with the delivery and outcomes. Although the study doesn’t demonstrate a causal link between badger vaccination and declining bTB, it does indicate that a larger-scale evaluation of badger vaccination is warranted.
The thematic analysis suggests two main reasons for the observed positive attitudes from farmers. The first is that the project was initiated by local farmers, rather than proposed or imposed from the outside. The second is that farmers appreciated the blood testing of badgers, which offered feedback on the likely success of the approach.
Policy implications
The authors suggest that the findings could “allay farmers’ fears that badger vaccination is impractical, expensive, and ineffective”. Indeed, they “provide grounds for optimism”. The study also shows that monitoring of M. bovis in badgers can encourage participation in vaccination efforts as well as measuring technical outcomes and highlights the importance of farmer-to-farmer networks in scaling badger vaccination to the level required to influence national bTB eradication. To mobilise these networks, the authors highlight the need for further implementation of “well-monitored badger vaccination”.
“Finally, our findings reinforce the importance of co-management and scientific evidence in fostering coexistence of people and wildlife.”
Professor Rosie Woodroffe, project lead and researcher at the ZSL Institute of Zoology, is quoted by the BBC reflecting on the devastating effects of bovine tuberculosis on farmers’ livelihoods.
“Everyone wants to see this disease eradicated. Our hope is that this work will help to move bTB control into a place where farmers and wildlife groups can work together towards this shared goal.”
Keith Truscott is founder of the Mid Cornwall Badger Vaccination Farmers Group and senior author on the report; he demands a “solution”.
“As a cattle farmer, I’m living with the constant worry that one of our cows might test positive for the disease, so doing nothing is not an option. I sleep better at night knowing that there are people out there working to eradicate the disease through vaccination.”
Professor Malcom Bennett, Professor of Zoonotic and Emerging Disease at University of Nottingham, describes the study as “interesting and useful”. Although, as the authors “rightly point out”, it is a “relatively small scale” study, it supports previous research that indicates that vaccination can “drive down TB in badger populations”. Furthermore, the collaboration between local farmers and landowners and researchers is an “important aspect” of the study.
“Badgers and their role in the epidemiology of bovine TB are controversial matters, with the ‘debate’ perhaps generating more heat than light. So that people who might take very different views – and the paper is strong on this – worked together is itself a hopeful sign.”
Professor Bennett calls for “further, bigger trials”, echoed by Professor James Wood, Infectious Disease Epidemiologist at the University of Cambridge and Co-Director of Cambridge Infectious Diseases, University of Cambridge.
“As the authors suggest, the findings vindicate that a larger scale study of badger vaccination, especially if farmer led, would be warranted. Scaling up this work is regarded by many as a particular challenge.”
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