A simulation model for the spread of bovine tuberculosis within New Zealand cattle herds

Bovine tuberculosis (bTB) remains a significant endemic pathogen of cattle herds, despite multi-decadal control programmes being in place in several countries. Understanding the risks of future bTB breakdown (BD) and the associated characteristics of herds and index breakdowns could help inform risk categorisation. Such risk categories could then contribute to tailored management and policies. Here, we estimated the future risk of herd BD for the cohort of herds that were derestricted during 2013 in Ireland using multivariable logit regression models, with a dominance analysis approach. One third of herds that were derestricted in 2013 experienced a breakdown during the follow-up five year period (1469/4459; 33%). BD length was a significant predictor of future risk, primarily driven by long BDs > 230 days relative to short BDs < 130 days (OR 95%CI: 1.157–1.851), as was having had a previous BD (OR 95%CI: 1.012–1.366). Herd-size was the dominant predictor of future risk (accounted for 46% of predicted variance), suggesting significant increase in risk of future breakdown with increasing (log) herd-size (OR 95%CI: 1.378–1.609). There was significant spatial variation in future risk across counties, and it was the second most dominant predictor of future risk (25% of predicted variance). The size of index breakdowns was not a strong predictor of future risk over a 5-year period. These findings can inform a risk-based policy development.

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Bovine tuberculosis control and eradication programs in Australia and New Zealand

Veterinary Microbiology ◽

10.1016/0378-1135(94)90044-2 ◽

1994 ◽

Vol 40 (1-2) ◽

pp. 23-39 ◽

Cited By ~ 77

Author(s):

Neil E. Tweddle ◽

Paul Livingstone

Keyword(s):

New Zealand ◽

Bovine Tuberculosis ◽

Tuberculosis Control ◽

Control And Eradication

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Using whole genome sequencing to investigate transmission in a multi-host system: bovine tuberculosis in New Zealand

BMC Genomics ◽

10.1186/s12864-017-3569-x ◽

2017 ◽

Vol 18 (1) ◽

Cited By ~ 31

Author(s):

Joseph Crispell ◽

Ruth N. Zadoks ◽

Simon R. Harris ◽

Brent Paterson ◽

Desmond M. Collins ◽

...

Keyword(s):

New Zealand ◽

Whole Genome Sequencing ◽

Genome Sequencing ◽

Bovine Tuberculosis ◽

Whole Genome ◽

Host System

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Evaluation of the sensitivity and specificity of bovine tuberculosis diagnostic tests in naturally infected cattle herds using a Bayesian approach

Veterinary Microbiology ◽

10.1016/j.vetmic.2011.07.034 ◽

2012 ◽

Vol 155 (1) ◽

pp. 38-43 ◽

Cited By ~ 51

Author(s):

Julio Álvarez ◽

Andrés Perez ◽

Javier Bezos ◽

Sergio Marqués ◽

Anna Grau ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Bayesian Approach ◽

Bovine Tuberculosis ◽

Diagnostic Tests ◽

Infected Cattle ◽

Cattle Herds

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Simulating the next steps in badger control for bovine tuberculosis in England

PLoS ONE ◽

10.1371/journal.pone.0248426 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0248426

Author(s):

Graham C. Smith ◽

Richard Budgey

Keyword(s):

Simulation Model ◽

Carrying Capacity ◽

Bovine Tuberculosis ◽

Management Strategies ◽

Fertility Control ◽

Host Population ◽

Dramatic Reduction ◽

Control Option ◽

Badger Vaccination ◽

The Uk

Industry-led culling of badgers has occurred in England to reduce the incidence of bovine tuberculosis in cattle for a number of years. Badger vaccination is also possible, and a move away from culling was “highly desirable” in a recent report to the UK government. Here we used an established simulation model to examine badger control option in a post-cull environment in England. These options included no control, various intermittent culling, badger vaccination and use of a vaccine combined with fertility control. The initial simulated cull led to a dramatic reduction in the number of infected badgers present, which increased slowly if there was no further badger management. All three approaches led to a further reduction in the number of infected badgers, with little to choose between the strategies. We do note that of the management strategies only vaccination on its own leads to a recovery of the badger population, but also an increase in the number of badgers that need to be vaccinated. We conclude that vaccination post-cull, appears to be particularly effective, compared to vaccination when the host population is at carrying capacity.

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Bovine tuberculosis and its risk factors among dairy cattle herds in and around Bahir Dar City, Northwest Ethiopia

Ethiopian Veterinary Journal ◽

10.4314/evj.v19i2.3 ◽

2015 ◽

Vol 19 (2) ◽

pp. 27 ◽

Cited By ~ 10

Author(s):

Anwar Nuru ◽

Gezahegne Mamo ◽

Leakemariam Teshome ◽

Aboma Zewdie ◽

Girmay Medhin ◽

...

Keyword(s):

Risk Factors ◽

Dairy Cattle ◽

Bovine Tuberculosis ◽

Northwest Ethiopia ◽

Bahir Dar ◽

Cattle Herds

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Assessment of the specificity of a gamma-interferon test performed with specific antigens to detect bovine tuberculosis, after non-negative results to intradermal tuberculin testing

Veterinary Record Open ◽

10.1136/vetreco-2019-000335 ◽

2019 ◽

Vol 6 (1) ◽

pp. e000335 ◽

Cited By ~ 1

Author(s):

Anne Praud ◽

Clémence Bourély ◽

Maria-Laura Boschiroli ◽

Barbara Dufour

Keyword(s):

Bovine Tuberculosis ◽

Gamma Interferon ◽

Skin Tests ◽

Negative Results ◽

In Series ◽

Specific Antigens ◽

Ifn Γ ◽

Tuberculin Testing ◽

Cattle Herds ◽

Higher Sensitivity

In cattle herds in France, cervical skin tests (STs) using simple intradermal tuberculin (SIT) are performed to detect bovine tuberculosis (bTB). When positive results are found on ST screening, the herd is considered to be ‘under suspicion’ and confined, raising economic issues. The suspicion can be lifted by carrying out a single intradermal cervical comparative test (SICCT) at least six weeks later.The authors conducted an experimental study in France between 2013 and 2015 to assess the accuracy of the gamma-interferon test (IFN-γ), used in series after a non-negative result to ST screening, and to study the possibility of replacing the SICCT performed six weeks later by an IFN performed within a few days. Data were collected concerning 40 infected and 1825 bTB-free animals from herds with non-negative results to ST screening. This study showed that the IFN-γ test based on specific antigens and performed within a few days of a non-negative result to the ST has higher sensitivity than the SICCT performed six weeks later and equal specificity. The IFN test is more convenient to perform; however, it is more expensive. The IFN-γ test based on MIX antigens may be a useful alternative to the SICCT, to shorten the confinement period of suspect herds without underdetecting bTB.

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