final report - ARCHIVE: Defra

Summary of recommendations
Pathogenesis
7 A full understanding of pathogenesis informs and underpins an understanding of the immune response,
and hence will enhance opportunities in both vaccine development and diagnosis. Strategic research
into the pathogenicity of Mb is therefore likely to contribute in the medium to long-term to new
approaches to control of the disease.
8 It is widely implied in the literature that the pathogenicity of Mb essentially parallels that of Mtb,
although the evidence base for this assumption is in some respects thin. Pathogenicity attributes, in
appropriate in vivo and in vitro models, of representative bovine and badger isolates of Mb should be
assessed to determine the validity of assumptions about the pathogenicity of Mb derived from studies
of Mtb. The same is true of the bovine immune response, and how it relates to the research in mice and
humans, which represents almost all the work done in this area.
9 A productive aspect of new research into the pathogenicity of Mb could be to focus on initial events
in Mb infection in an appropriate model. Adhesion mechanisms and the role of antibodies at mucosal
surfaces appear to have been relatively neglected in research into both Mtb and Mb and could be
appropriate foci for future study.
10 The genome sequences of a cross-section of Mb isolates from cattle, badgers and environmental
sources should be determined by next-generation sequencing technologies. This will allow a number
of important investigations:
(a)
(b)
The evaluation of variation in pathogenicity-associated genes, enabling inferences to be made
about their likely role in virulence;
An assessment of the hypothesis that the current epidemic is due to the emergence of a badgeradapted
ecotype.
Environment and epidemiology
11 There is an urgent need to limit the spread of bTB through integrating the knowledge currently
available to develop improved control strategies. For example, modelling studies might be encouraged
to explore new approaches to better control the spread of bTB, such as zoning.
12 There remains a requirement to enhance the coordination of the many different research projects
investigating different facets of the bTB problem. This should result in various sources of data being
more widely available to researchers. This might prove particularly rewarding for modelling projects.
13 There do not appear to be sufficient detailed descriptive statistics available for general research purposes
into bTB and this indicates the need for further in-depth longitudinal study of affected herds.
14 Further investigation is needed into animal behaviour and farming practices that increase the likelihood
of indirect or (especially) direct contact between badgers and cattle, both while cattle are at pasture and
while they are housed on farm premises. The aim would be to identify high-risk situations towards
which appropriate control measures could be targeted.
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