1 / 18

Tb Breakdown Still a Zoonotic Risk!

Tb Breakdown Still a Zoonotic Risk!. Paul Doran VI Enniscorthy DVO. Tb Breakdown - Still a Zoonotic Risk!. Epidemiological Investigation (ER76) Herd History Herd Composition and Breakdown Test Management System Spread of Disease Source? Critical Issues Animal Infection

rob
Download Presentation

Tb Breakdown Still a Zoonotic Risk!

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tb BreakdownStill a Zoonotic Risk! Paul Doran VI Enniscorthy DVO

  2. Tb Breakdown - Still a Zoonotic Risk! • Epidemiological Investigation (ER76) • Herd History • Herd Composition and Breakdown Test • Management System • Spread of Disease • Source? • Critical Issues • Animal Infection • Human Infection • Lessons Learned

  3. Herd Tb History • 1993 - 1 reactor • 1995 - 5 reactors • Mar 2003 - 1 reactor (3yo cow, retropharyngeal Tb-type lesion on gross PM) • Apr 2004 – Tb+ive factory lesion in aged cow • Mar 2005 – Breakdown Test

  4. Breakdown Test • Post De-Restriction CT in March 2005 • Dairy Herd – 100 Cattle – 6 reactors • 38 Cows – 2 reactors • 32 Steers – 2 x 1y.o. + 2 x 2y.o. reactors (1L) • 8 Heifers • 22 Calves • Risk Status D → H • ⇒Epidemiological Investigation (ER 76)

  5. Herd Management - Grazing

  6. Herd Management - Housing

  7. Herd Management - General • Closed Herd - No purchased animals • No sharing of machinery, housing, crushes, personnel • Slurry/dung spread by herdowner • Well fenced, no contact with other cattle • Water Supply – mains and on-farm well

  8. Wildlife/Contiguous Herds • No goats or deer • Badger activity on grazing fragments/adjoining lands • Low level incidence on two contig. herds • No current evidence of contiguous infection

  9. Er 76 – Preliminary Assessment of Cause Residual infection (confirmed TB in April 2004) Wildlife source (probable??)

  10. Spread of Disease • R/R June 2005 – 21 reactors • 5 cows (0 L) • 1 x 2yo (1L) • 1 x 1yo (0L) • 10 autumn calves (8L) • 4 spring calves (3L) • Back to the drawing board!

  11. Spread of Disease – Cow 044 • Calved Jan ’05 • High Somatic Cell Count • Chronic Mastitis over two lactations • Milk fed to group of 28 Calves + 1 x 2yo • TB tested 7 times since 2003 • Blood tested: +ive anamnestic Elisa • Milk Sample: +ive M.bovis • PM -Supramammary Lymph Node: NVL, +ive M.bovis

  12. Somatic Cell Count

  13. Further Testing • R/R Sept 2005 - 11 test reactors • 3 autumn calves • 8 spring calves • 4 in-contacts removed • 2 R/R’s in Dec 2005 and Feb 2006 - Clear • Post De-Restriction CT Aug 2006 - Clear • Classification Related SCT Feb 2007 – Clear • Classification Related SCT Aug 2007 – 4 test reactors • 4 cows (incl. 2 cohorts of Cow 044)

  14. Wildlife Capture • 1st Capture (Oct 2005) • 20 Badgers (7 confirmed Tb) KilkennyRVL/UCD • Gross PME: 1 lesion • Histopath: 2+ive TB • Culture: 5+ive M.bovis • 2nd Capture (Feb 2006) • 21 Badgers (4 confirmed Tb) KilkennyRVL/Equine Centre • Gross PME: 1 lesion • Histopath: 3+ive TB • Culture: 3 +ive M.bovis • 11 Badgers with Confirmed Tb = 34%of those examined by histopath and/or culture

  15. Cattle Infection Source ? • F/L aged cow June 2004 • SCC in 044 elevated from June 2004 • Wildlife ? • Latency ? Spread ? • Respiratory ? • Oral (Mastitis)

  16. Human Infection • Cow044 – Milk to bulk tank “once or twice” • Family consumed unpastuerised milk • 3 Adults, 3 Children • 5/6 +ive Mantoux tests • Clinical Signs • Treatment • Remission • Recurrence

  17. Lessons • Epidemiological Investigations Keep an open mind! • Remember Tb still a Zoonosis • Preventable

  18. Thanks • Herdowner’s Family • Kilkenny RVL • Eamon Costello • Denise Murphy • Dan Collins • Simon More • John Carson

More Related