Dr. Aaron Lower, Carthage Veterinary Service, Ltd, 2014 Pork Management Conference, June 17-20 in Tampa, Florida.

1. PEDv
Pork Management Conference
June 19, 2014
Carthage Veterinary Service, Ltd.
alower@hogvet.com

2. 2
Carthage Veterinary Clinic Hancock Veterinary Clinic
Carthage, IL
Suzhou, China
Solutions for the Food Supply Chain

3. Epidemic
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4. 4

5. PEDv Worldwide
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Beek, Vincent

6. Genetics
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Woo, et al. J. Virol. 2012

7. 7
PEDv

8. Swine Deltacoronavirus (SDCoV)
• Non-PED coronavirus
– Clinical signs similar to PED and TGE
– 40% PWM for 2-3 weeks
• Described in Hong Kong - 2012
• First case - June 5, 2013
• Diagnostic capabilities
– SDCv PCR
– No serological testing
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ADDL

9. 9
Woo, et al. J. Virol. 2012

10. 10
SDCoV
Woo, et al. J. Virol. 2012

11. Porcine Deltacoronavirus Bioassay
• Nine - 14 day old piglets
– Inoculated with PDCoV from field samples
• Euthanized on:
– Day 2 post-infection (PI)
– Day 4 PI
– Day 6 PI
• Showed no evidence of enterocyte infection
• Negative for PDCoV by RT-PCR
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University of Minnesota

12. Porcine Deltacoronavirus
Retrospective analysis
• 30% positive rate on cases
• Co-infection (PEDv, TGEv, RVA, RVB, RVC)
– 78% positive for PEDv, RVA, RVB, and/or RVC
– RVC positive >50% of the samples
• 4 complete genomes
– US isolates - 99.8% similar
– Chinese strain - 98.9% - 99.2% similar
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University of Minnesota

13. Outbreak Management
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Day 0
• Wean down in age
• Begin oral live virus exposure
• +/- oral progestins
Day 1-5
• Aggressive oral live exposure
Day 6-
14
• Euthanize all piglets born
• SANITATION

14. PEDv Impact
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15. PEDv Impact
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16. Euthanize pigs on Day 0 – 14 days
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Courtesy of Dr. Jim Lowe

23. Herd Eradication Management
• Aggressive sanitation
– Double de-grease, Double wash, Double disinfect
rooms
• 2 nights downtime
• Wash sows prior to loading
– No carts, change shoe
– Full McREBEL
– Do not touch pigs till day 7
– Wash gestation barns continuously
– Wash hallways after every pig movement
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24. Antibody Response
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ISU. Gimenez-Lirola. NPB #13-264

25. 25
Song, D. Park, B, Virus Genes, 2012

26. 26
SDSU. Clement. NPB #13-263

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SDSU. Clement. NPB #13-263

28. Conditional Vaccine License
Harrisvaccines, Inc
• June 16, 2014 approval
• Qualifications:
– Safety
– Purity
– Reasonable expectation of efficacy
• Long term – Modified Live Vaccine
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29. PRRS and PEDv Site Classification
Guidelines
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PEDv Site Classification
I Infected and Shedding
II Stable, Weaned pigs are negative for PEDv
III Provisionally Negative
IV Negative
PRRS Site Classification
1 Positive Unstable
2v Positive stable, Ongoing exposure
2 Positive Stable
3 Provisionally Negative
4 ELISA Negative

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31. What do we need to learn?
• Epidemiology
– Watch Canada
• Have they identified a key transmission route?
• Feed risk
– Origin of viral introduction to the US
• Herd stability/eradication
– Poor immune response or viral load?
– Vaccine development
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32. Canadian PEDv
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62 cases in Ontario
Accessed on 06/16/2014. http://www.ontariopork.on.ca/ped/ComfirmedCases.aspx

33. Carthage Veterinary Service, Ltd

34. PEDv – Late Finishing Infection
• Looseness observed 2 days prior to ADFI drop
– 7 lb/day prior to break
– 2 lb/day at peak - ~80% reduction 2-3 days
• ADG
– Reduced 31% Day 0-7 post infection
• F/G
– No significant difference
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35. PEDv – Late Finishing Infection
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Water Intake
– Depressed for 7 days

36. One positive trailer in means 1.7
positive trailers at exit
Plant
Contaminated
at entry
Contaminated
at Plant
Contamination
Ratio
A 2.25% 8.05% 3.58
B 7.00% 4.30% 0.61
C 10.84% 10.81% 1.00
D 2.00% 0.00% 0.00
E 14.56% 3.08% 0.62
G 3.00% 1.03% 0.34
All 5.98% 4.31% 0.72

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38. Biosafety of Spray Dried Plasma
Relative to PEDv
1. PEDv does not survive spray-drying
2. Experimentally inoculated spray-dried plasma loses infectivity by 7
days when stored at room temperature
3. Retained samples from Canadian lot of spray-dried porcine
plasma and 2 other samples of PCR positive commercial spray-
dried porcine plasma did not contain infective PED virus
1. FDA acquired samples of the specific lot were negative on bioassay
4. Weaned pigs fed a diet with 5% PCR positive spray-dried plasma
for 14 days post weaning remained PEDv negative for the 21 day
feeding period
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APC Tech Brief – April, 2014

39. Biosafety of Spray Dried Plasma
• Additional Questions
– Is the lab simulation of spray drying similar to the
actual process?
– What is the sensitivity of the bioassay?
– Does the lab strain of PEDv have the same
survivability to the field strain?
– Do all spray dry plants use the same processing
parameters?
– What is the variation in the plasma production
process?
– What are the QA/QC procedures involved?
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40. Working Group
Focusing on research, control, and contamination – 4 Priorities:
• To investigate the effectiveness and cost of treatments that
could be used to mitigate the survival of PEDV and other
viruses in feeds
• To conduct contamination risk assessments at all steps within
the feed processing and delivery chain
• To develop a substitute for the currently used swine bioassay
procedures
• To continue to investigate the risk of feed and other pathways
for pathogen entry into the U.S.
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