Aligning Waiting Periods                 forVaccinate-to-live & Vaccinate-to-die                   PLENARY Session II:    ...
Presentation Outline   Context of the QUAD FMD Project   What did the QUAD FMD Code Project conclude?   What is the rat...
Context      In April, 2011 QUAD CVOs tasked a scientific       literature review to see if support for alignment       o...
ContextVaccinate-to-dieVaccinate-to-live            10/28/2012             4
Presentation Outline   Context of the QUAD FMD Project   What did the QUAD FMD Code Project conclude?   What is the rat...
Conclusion   Alignment for vaccinate-to-live and vaccinate-to-    die is NOT feasible for all commodities   But is feasi...
Presentation Outline   Context of the QUAD FMD Project   What did the QUAD FMD Code Project conclude?   What is the rat...
RationaleHISTORICAL: No specific scientific rationale for OIE waiting periodsYears: achieve-with vacc; without vacc/recov...
RationaleVACCINOLOGY: Higher potency (≥ 6PD50) vaccines protect earlier;  single dose; last longer. FMDV replication eve...
RationaleCARRIER: Anecdotal only; No experimental studies show cattle-  cattle transmission; only SAT2 African buffalo-ca...
RationaleDIVA OR NSP ASSAYS: PANAFTOSA tests, recognized by OIE, are the  foundation to FMD eradication in South America...
RationaleSURVEILLANCE: Demonstrate absence of infection impossible in a  vaccinated population (demonstrate is used in  A...
RationaleAnimal Products: [Commodity based trade] Risk of FMDV from vaccinated products can  be negligible with risk miti...
Rationale10/28/2012               14
Presentation Outline   Context of the QUAD FMD Project   What did the QUAD FMD Code Project conclude?   What is the rat...
Conclusions (repeat)   Alignment of a 3 month waiting period for vaccinate-to-    live and vaccinate-to-die is feasible p...
Recommendations      Code needs definitions for “emergency” vaccination,       FMDV “circulation” versus “infection”    ...
Presentation Outline:            FMD vaccinate-to- live   Context of the QUAD FMD Project   What did the QUAD FMD Code P...
Current Status1.    Propose alignment of waiting periods for      vaccinate-to-live and vaccinate-to-die to the      OIE (...
Next Stepsc)   Tabled at SCAD at     end of August 2012d)   Referred back to ad     hoc FMD Working     Group with written...
Next StepsEU Support ?   A principle conclusion of the EU Tervuren    workshops in 2007 was “Vaccination-to-live    polic...
Acknowledgements   QUAD CVOs       Paul Barnett (IAH, NETWORK)- Vaccinology       Grant Clarke (New Zealand) - DIVA    ...
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Session 2: Aligning waiting periods for vaccinate-to-live & vaccinate-to-die

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The CVOs of Australia, Canada, New Zealand and the USA initiated a scientific review to evaluate if waiting periods to regain OIE status of FMD free not practising vaccination could be 3 months irrespective of whether vaccinate-to-live or vaccinate-to-die policies were applied.

The authors reviewed the following designated areas reflecting their expertise [historical review of waiting periods; Carriers; Vaccinology; DIVA technology; Post Outbreak Surveillance and Animal Products].

Current science supports eligibility to return to OIE status of FMD free country where vaccination is not practised in 3 months following an outbreak where stamping-out and
emergency vaccination using higher potency vaccines are applied irrespective of whether vaccinate-to-live or vaccinate-to-die policies. This assumes aspects of vaccination affecting
population immunity such as insufficient match, inadequate coverage, incorrect storage, application, maternal antibody etc are addressed. The alignment of the 3 month waiting period applies only to animal products as in 2006, the Code restricted export of live vaccinated animals from a FMD free country not practising vaccination. However, countries with OIE status, FMD free country where vaccination is practised may accept vaccinated animals and those with no OIE FMD status should not refuse them as per the OIE Code User Guide Part C a). Bilaterally negotiated additional risk mitigation measures may be needed to meet individual importing countries’ Appropriate Level of Protection (ALOP) as in any application of the Code.

(c) D.Geale / EuFMD (eufmd@fao.org)

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Session 2: Aligning waiting periods for vaccinate-to-live & vaccinate-to-die

  1. 1. Aligning Waiting Periods forVaccinate-to-live & Vaccinate-to-die PLENARY Session II: FOCUS ON ISSUES AFFECTING FMD CONTROL IN FMD FREE REGIONS Project Leader: Dorothy Geale (Canada) Project Team: Paul Barnett (IAH, Pirbright, United Kingdom) Grant Clarke (New Zealand) Jennifer Davis (Australia) Thomas Kasari (United States)
  2. 2. Presentation Outline Context of the QUAD FMD Project What did the QUAD FMD Code Project conclude? What is the rationale for this conclusion?  Historical basis for 3 and 6 months  Vaccinology/Carrier/Subclinical  DIVA  Post Outbreak Surveillance  Animal Products Conclusion/Recommendations Next Steps 10/28/2012 2
  3. 3. Context  In April, 2011 QUAD CVOs tasked a scientific literature review to see if support for alignment of waiting periods for vaccinate-to-live and vaccinate-to-die strategies Core Project Team  Desirable Outcomes  Dorothy Geale*of economic impediment Grant Clarke (New  Removal (Canada), Tom Kasari (USA), for vaccinate-to- Zealand), Jennifer Davis (Australia), Paul Barnett (WRL FMD) live strategies Collaboration with IAH, Pirbright  Timely decision making regarding FMD vaccination  International FMD Strategic Reserves NETWORK project;  Global reduction of mass culling of livestock through Work vaccination in a FMD outbreak Vaccinology, DIVA, streams History of 3/6 mos, Post-outbreak Surveillance & Trade in animal product 10/28/2012 3
  4. 4. ContextVaccinate-to-dieVaccinate-to-live 10/28/2012 4
  5. 5. Presentation Outline Context of the QUAD FMD Project What did the QUAD FMD Code Project conclude? What is the rationale for this conclusion?  Historical basis for 3 and 6 months  Vaccinology/Carrier/Subclinical/DIVA  Post Outbreak Surveillance  Animal Products Conclusions/ Recommendations Next Steps 10/28/2012 5
  6. 6. Conclusion Alignment for vaccinate-to-live and vaccinate-to- die is NOT feasible for all commodities But is feasible for vaccinated animal products using higher potency FMD vaccines Incremental risk of vaccinated animal products can be deemed negligible with additional risk mitigation measures to meet ALOP. Note Code Article 8.5.9.1 b) and c), deals ONLY with animal products not animals which are restricted by Article 8.5.12 3) 10/28/2012 6
  7. 7. Presentation Outline Context of the QUAD FMD Project What did the QUAD FMD Code Project conclude? What is the rationale for this conclusion?  Historical basis for 3 and 6 months  Vaccinology/Carrier/Subclinical/DIVA  Post Outbreak Surveillance  Animal Products Conclusions/Recommendations Next Steps 10/28/2012 7
  8. 8. RationaleHISTORICAL: No specific scientific rationale for OIE waiting periodsYears: achieve-with vacc; without vacc/recover-with vacc; without vacc  Prior to 1992: 2 yr; 3 yr /6 mos  1992-1998: 2 yr; 12 mos/12 mos; 6 mosVaccinate-to-live  1998-2002: 2 yr; 12 mos/12 mos; 3 mos; 3mos  2002 to present: 2 yr; 12 mos/6 mos (DIVA); 3mos; 3mos; 6mos (DIVA). Relative risk determined by SCAD in 6 mos blocks for free with vacc and 3 mos for free without vaccVaccinate-to-live 10/28/2012 8
  9. 9. RationaleVACCINOLOGY: Higher potency (≥ 6PD50) vaccines protect earlier; single dose; last longer. FMDV replication even inhibited in some animals experimentally proven relationship with potency Infection chain is broken in 1/2 the time; less FMDV in environment exponentially = less challenge dose No unequivocal experimental evidence that conventional vaccine which protects against disease also reduces susceptibility to infection, virus excretion or duration of persistence 10/28/2012 9
  10. 10. RationaleCARRIER: Anecdotal only; No experimental studies show cattle- cattle transmission; only SAT2 African buffalo-cattle Undefined trigger? Strain, serotype & challenge dose differences? Modeling with high potency parameters suggests prevalence of carrier herds is very low 0.2% with one carrier per herd Does waiting 6 vs 3 mos make a difference? Perhaps live animals but for animal products? 10/28/2012 10
  11. 11. RationaleDIVA OR NSP ASSAYS: PANAFTOSA tests, recognized by OIE, are the foundation to FMD eradication in South America High potency vaccines are more purified DIVA kits available with Se (68-94%) & Sp (97- 98%) but Se improved using tests in series. DIVA validated at the herd level (appropriate for products) but lacks Se for individual animal level (already restrict live vaccinates) 10/28/2012 11
  12. 12. RationaleSURVEILLANCE: Demonstrate absence of infection impossible in a vaccinated population (demonstrate is used in Article 8.5.9.1 c); use “substantiate” for “demonstrate” as NSP assays lack Se. Even census surveillance (EU) does not provide absolute certainty; S Korea used <1% prevalence. South America 5% @ 95%(follow-up per Code 8.5.49) Need to change OIE paradigm from waiting time to Sentinels of limited use due to low transmission statistical certainty or concept of threshold of surveillance (long term solution) 10/28/2012 12
  13. 13. RationaleAnimal Products: [Commodity based trade] Risk of FMDV from vaccinated products can be negligible with risk mitigation measures Risk of mechanical contamination from carriers is negligible if correctly processed Neutralizing antibodies are best guarantee of the absence of FMDV; No Code for milk from vaccinates Embryos are not a risk provided handled as per IETS Manual (2007) 10/28/2012 13
  14. 14. Rationale10/28/2012 14
  15. 15. Presentation Outline Context of the QUAD FMD Project What did the QUAD FMD Code Project conclude? What is the rationale for this conclusion?  Historical basis for 3 and 6 months  Vaccinology/Carrier/Subclinical/DIVA  Post Outbreak Surveillance  Animal Products Conclusions/Recommendations Next Steps 10/28/2012 15
  16. 16. Conclusions (repeat) Alignment of a 3 month waiting period for vaccinate-to- live and vaccinate-to-die is feasible provided the incremental risk of vaccinated animal products is deemed negligible with additional risk mitigation. Article 8.5.9.1 b) and c), deals ONLY with animal products as animals are restricted by Article 8.5.12 3) Additional risk mitigation measures determined bilaterally to meet ALOP but may include bovine only (DIVA herd validated); animal identification & traceabilitiy; protection zone vaccination only; serology; no wildlife reservoir etc 10/28/2012 16
  17. 17. Recommendations  Code needs definitions for “emergency” vaccination, FMDV “circulation” versus “infection”  OIE convene ad hoc group to define statistical certainty or threshold ,of surveillance to demonstrate the absence of FMDV infection and FMDV circulation.  DIVA for higher potency vaccines for all species.  Promote novel vaccine such as marker VP1 gene segment with duplicate DIVA capability.  Encourage concurrent revision of EU 2003/85/EC.Article 62 of this Directive permits derogation of the OIE waiting periods of 3 and 6 mos. provided, “…the clinical and serological survey provided for in Article 56 and the measures provided for in Article 57 have been completedand confirmed the absence of foot-and-mouth disease virus infection” (EU, 2003). 10/28/2012 17
  18. 18. Presentation Outline: FMD vaccinate-to- live Context of the QUAD FMD Project What did the QUAD FMD Code Project conclude? What is the rationale for this conclusion?  Historical basis for 3 and 6 months  Vaccinology/Carrier/Subclinical/DIVA  Post Outbreak Surveillance  Animal Products Conclusions/Recommendations Next Steps 10/28/2012 18
  19. 19. Current Status1. Propose alignment of waiting periods for vaccinate-to-live and vaccinate-to-die to the OIE (8.5.9 1. b) & c) a) Concept presentation was made at July 3-5 ad hoc FMD Group under SCAD b) Formal letter to Dr Vallat from QUAD CVOs on August 1 with revised QUAD paper with scientific evidence to support Code change 10/28/2012 19
  20. 20. Next Stepsc) Tabled at SCAD at end of August 2012d) Referred back to ad hoc FMD Working Group with written rationalee) To be reviewed in Code Commission meeting February 2013 10/28/2012 20
  21. 21. Next StepsEU Support ? A principle conclusion of the EU Tervuren workshops in 2007 was “Vaccination-to-live policy with subsequent freedom from infection substantiated by a survey system including NSP testing is a realistic and achievable option in FMD control.” 10/28/2012 21
  22. 22. Acknowledgements QUAD CVOs  Paul Barnett (IAH, NETWORK)- Vaccinology  Grant Clarke (New Zealand) - DIVA  Jennifer Davis (Australia) – Animal Products  Thomas Kasari (United States)- Surveillance QUAD CVOs  John Clifford (United States)-  Brian Evans/Francine Lord ( Canada)   Mark Schipp (Australia) Matthew Stone (New Zealand) Questions? Technical Reviewers  QUAD EMWG Reviewers  Soren Alexandersen  Jane Rooney/ Pam Hullinger/Randy Crom/Hernando Duque  Alex Donaldson  Tom Smylie/ Jim Clark/ Al Barton/ Randy Morley  Paul Kitching  Andre van Halderen/ Katie Owen/ Brendan Pollard  Victor Saraiva  Jill Mortier/ Dick Rubira  Keith Sumption  Gavin Thomson 10/28/2012 22

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