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The variability and seasonality of the environmental reservoir of Mycobacterium bovis shed by wild European badgers.

King HC, Murphy A, James P, Travis E, Porter D, Hung YJ, Sawyer J, Cork J, Delahay RJ, Gaze W, Courtenay O, Wellington EM - Sci Rep (2015)

Bottom Line: The incidence of Mycobacterium bovis, the causative agent of bovine tuberculosis, has been increasing in UK cattle herds resulting in substantial economic losses.The European badger (Meles meles) is implicated as a wildlife reservoir of infection.Here we identify potential infection hotspots in the badger population and quantify the heterogeneity in bacterial load; with infected badgers shedding between 1 × 10(3)- 4 × 10(5) M. bovis cells g(-1) of faeces, creating a substantial and seasonally variable environmental reservoir.

View Article: PubMed Central - PubMed

Affiliation: University of Warwick, School of Life Sciences, Gibbet Hill Campus, Coventry, CV4 7AL.

ABSTRACT
The incidence of Mycobacterium bovis, the causative agent of bovine tuberculosis, has been increasing in UK cattle herds resulting in substantial economic losses. The European badger (Meles meles) is implicated as a wildlife reservoir of infection. One likely route of transmission to cattle is through exposure to infected badger urine and faeces. The relative importance of the environment in transmission remains unknown, in part due to the lack of information on the distribution and magnitude of environmental reservoirs. Here we identify potential infection hotspots in the badger population and quantify the heterogeneity in bacterial load; with infected badgers shedding between 1 × 10(3)- 4 × 10(5) M. bovis cells g(-1) of faeces, creating a substantial and seasonally variable environmental reservoir. Our findings highlight the potential importance of monitoring environmental reservoirs of M. bovis which may constitute a component of disease spread that is currently overlooked and yet may be responsible for a proportion of transmission amongst badgers and onwards to cattle.

No MeSH data available.


Related in: MedlinePlus

Distribution of M. bovis genome equivalents in positive samples by social group.
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f3: Distribution of M. bovis genome equivalents in positive samples by social group.

Mentions: Significant variability in genome equivalents was identified both within and between social groups (Fig. 3) with social groups Nettle, Top, Septic Tank and West shedding more cells over the year than the other social groups (Table 1). Social groups with a high percentage of positive samples consistently shed amongst the highest cumulative numbers of M. bovis cells during the year (Table 1). Social group Old Oak was exceptional as it has one of the highest cumulative M. bovis genome equivalent values yet had the lowest percentage of positive samples in the study (Table 1). This distribution is consistent with the presence of a relatively small number of animals shedding large amounts of bacteria in some groups. However, as we could not assign faecal samples to individuals we cannot discount within-individual variation in shedding from being responsible for this observation. Hence the need for further research into heterogeneity in transmission risks amongst individual badgers.


The variability and seasonality of the environmental reservoir of Mycobacterium bovis shed by wild European badgers.

King HC, Murphy A, James P, Travis E, Porter D, Hung YJ, Sawyer J, Cork J, Delahay RJ, Gaze W, Courtenay O, Wellington EM - Sci Rep (2015)

Distribution of M. bovis genome equivalents in positive samples by social group.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4527091&req=5

f3: Distribution of M. bovis genome equivalents in positive samples by social group.
Mentions: Significant variability in genome equivalents was identified both within and between social groups (Fig. 3) with social groups Nettle, Top, Septic Tank and West shedding more cells over the year than the other social groups (Table 1). Social groups with a high percentage of positive samples consistently shed amongst the highest cumulative numbers of M. bovis cells during the year (Table 1). Social group Old Oak was exceptional as it has one of the highest cumulative M. bovis genome equivalent values yet had the lowest percentage of positive samples in the study (Table 1). This distribution is consistent with the presence of a relatively small number of animals shedding large amounts of bacteria in some groups. However, as we could not assign faecal samples to individuals we cannot discount within-individual variation in shedding from being responsible for this observation. Hence the need for further research into heterogeneity in transmission risks amongst individual badgers.

Bottom Line: The incidence of Mycobacterium bovis, the causative agent of bovine tuberculosis, has been increasing in UK cattle herds resulting in substantial economic losses.The European badger (Meles meles) is implicated as a wildlife reservoir of infection.Here we identify potential infection hotspots in the badger population and quantify the heterogeneity in bacterial load; with infected badgers shedding between 1 × 10(3)- 4 × 10(5) M. bovis cells g(-1) of faeces, creating a substantial and seasonally variable environmental reservoir.

View Article: PubMed Central - PubMed

Affiliation: University of Warwick, School of Life Sciences, Gibbet Hill Campus, Coventry, CV4 7AL.

ABSTRACT
The incidence of Mycobacterium bovis, the causative agent of bovine tuberculosis, has been increasing in UK cattle herds resulting in substantial economic losses. The European badger (Meles meles) is implicated as a wildlife reservoir of infection. One likely route of transmission to cattle is through exposure to infected badger urine and faeces. The relative importance of the environment in transmission remains unknown, in part due to the lack of information on the distribution and magnitude of environmental reservoirs. Here we identify potential infection hotspots in the badger population and quantify the heterogeneity in bacterial load; with infected badgers shedding between 1 × 10(3)- 4 × 10(5) M. bovis cells g(-1) of faeces, creating a substantial and seasonally variable environmental reservoir. Our findings highlight the potential importance of monitoring environmental reservoirs of M. bovis which may constitute a component of disease spread that is currently overlooked and yet may be responsible for a proportion of transmission amongst badgers and onwards to cattle.

No MeSH data available.


Related in: MedlinePlus