PRRS The Challenge Continues. Cameron Schmitt, DVM, MS Iowa Pork Congress

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1 PRRS The Challenge Continues Cameron Schmitt, DVM, MS Iowa Pork Congress

2 My Background 2002 graduate of Iowa State University Completed DVM and MS (Veterinary Microbiology) Joined Pipestone Vet Clinic in 2002 Started Pipestone Vet Clinic of Iowa 2008 Married, 3 boys

4 Outline Biosecurity Review Transmission Filtration Immunological Review Vaccines Sow Farm Clean up Epidemiological Data Summary Comments

5 PRRS Biosecurity Transmission via: Animals Semen Fomites Air

6 Biosecurity - Animals Animals are the highest risk for PRRS transmission They propagate the agent Shed in all secretions/excretions

7 Biosecurity - Animals Animals Sow Herds Gilts It is critical to have isolation/quarantine space for breeding herds Testing placement and 2 weeks post placement Oral Fluids or Serum Wean-to-Finish sites All In/All Out flow Continuous flow sites tend to circulate PRRS and other diseases once infected

8 Biosecurity - Semen Semen is still a risk today Critical to work with a reputable source and understand their testing protocols Do not use semen until test cleared for the batch/boars that collection day

9 Biosecurity - Fomites Standardized D&D D&D = Disinfection and Down time All inanimate objects entering a farm subject to D&D Spray all materials, equipment, etc with Synergize and dry 1 hour and Dry are the critical elements must meet both criterion

10 Biosecurity - Trucks Transport is highly correlated with most disease movement Are your trucks clean, really clean? Inspected? Audited? The industry needs to re-evaluate current transport biosecurity

11 Biosecurity - Air A lot of new knowledge we continue to learn

12 Aerosols Viral quantities found in air were significantly higher in 2011 than in previous years Hypothesized strains continue to become more virulent/more readily shed Vaccination with Modified Live Vaccines significantly reduces aerosol shedding Vaccination of sites surrounding sow farms is a good idea

13 * It was used one cyclonic collector for each room Project 1: Experimental design D&D West Controls Treatments Challenge Control Room (West) Challenge Vaccine Room (East) 1,000 pigs PRRSv infected Sham inoculated 2x saline 1,000 pigs PRRSv infected Vaccinated 2x ATP D&D East

14 Results (Linhares et al., Vaccine, 2011) Outcome Vaccine group Control group # PRRSV positive air days* Duration of aerosol shedding* 17 days 31 days 45 days 70 days * = Differences significant at p < 0.05

15 Project 2 Recently completed: Vaccinate first Challenge second Outcomes: shedding and performance

16 * It was used one cyclonic collector for each room Experimental design D&D West Controls Treatments Challenge Control Room (West) Challenge Vaccine Room (East) 1,000 pigs Sham inoculated 1x saline Challenged ,000 pigs Vaccinated 1x MLV Challenged D&D East

17 8/15/2012 8/16/2012 8/17/2012 8/18/2012 8/19/2012 8/20/2012 8/21/2012 8/22/2012 8/23/2012 8/24/2012 8/25/2012 8/26/2012 8/27/2012 8/28/2012 8/29/2012 8/30/2012 8/31/2012 9/1/2012 9/2/2012 9/3/2012 9/4/2012 9/5/2012 6/12/2012 6/13/2012 6/14/2012 6/15/2012 6/16/2012 6/17/2012 6/18/2012 6/19/2012 6/20/2012 6/21/2012 6/23/2012 6/24/2012 6/25/2012 6/26/2012 6/27/2012 6/28/2012 6/29/2012 6/30/2012 7/1/2012 7/3/2012 7/4/2012 7/5/2012 7/6/2012 7/7/2012 7/8/2012 7/9/2012 7/10/2012 7/11/2012 7/12/2012 7/13/2012 7/14/2012 7/15/2012 7/16/2012 7/17/2012 7/18/2012 7/19/2012 7/20/2012 7/21/2012 7/22/2012 7/23/2012 7/24/2012 7/25/2012 7/26/2012 7/27/2012 7/28/2012 7/29/2012 7/30/2012 7/31/2012 8/1/2012 8/2/2012 8/3/2012 8/4/2012 8/5/2012 8/6/2012 8/7/2012 8/8/2012 8/9/2012 8/10/2012 8/11/2012 8/12/2012 8/13/2012 8/14/2012 Preliminary data: Air Sampling Days From Inoculation Treatment Group North - NoVax South - Vax Days From Innoculation Treatment Group North - NoVax South - Vax

18 Filtered Farms Filter bypass continues to be a challenge Backdrafting through fans Filter Box design/seal Cracks, leaks, drains, etc.

19 Filter Farm Data Our data would indicate there is a significant reduction in the frequency of PRRS infections on filtered farms, but it isn t perfect When comparing pre and post filtration, we are observing a 61% reduction in new viral introductions

20 Breeding herds The impact of air filtration is significant, but not perfect Pre-filtration Postfiltration New PRRSV infection Time pre and post air filtration (months)

21 How often are farms challenged? PRRS

Recipient Populations: Perimeter Testing 5 filtered farms selected for sampling Recipient farms (PRRSV-negative) n = 4 sampled 30 m outside of building collector placed into direction of prevailing

22 Recipient Populations: Perimeter Testing 5 filtered farms selected for sampling Recipient farms (PRRSV-negative) n = 4 sampled 30 m outside of building collector placed into direction of prevailing wind Source farm (PRRSV-positive) n =1 sampled at exhaust fan 1 mile SE of neighboring recipient farm Daily air sampling: March 1-31, 30 minutes per day Outcomes Frequency: # PCR-positive air days Dose: Quantity of viable virus (TCID50/mL) Diversity: ORF 5 sequencing of selected samples

23 Farm 4 Farm 3

24 Results Frequency Farm number PRRSV positive air days 1 (recipient) 64% 2 (recipient) 41% 3 (source) 75% 4 (recipient) 65% 5 (recipient) 0% Historical 3-11%

25 Log concentration virus Dose Farm2 Farm 3 Farm1 Farm 4 Farm Historical ANOVA Farm 1 a Farm 2 a Farm 3 a Farm 4 a Historical b

26 # sequences Diversity Recipient Recipient Recipient (new) (new) (MLV) (old) (new) (new) (n=2) Source (source), (ATP) (source) (source) (n=2) (source) Farm number

27 Conclusions Under the conditions of this study: 1. Viral loads in aerosols from source populations infected with new variants were significantly higher than historical levels. 2. PRRSV aerosol challenge of recipient populations was a frequent event. 3. Viral loads in recipient aerosol samples collected at the perimeter level were significantly higher than historical levels. 4. Extensive viral diversity was observed in air samples collected around the perimeter of recipient populations.

28 Slurry Pigs shed PRRS in feces for 7 days Virus survives in slurry for 14 days at 40 degrees and 5 days at degrees Virus survival in solids is less than 14 days in standard pit environments Virus is aerosolized during agitation if population is shedding virus Virus can be found at least at 30 meters from applicators during application Pumping equipment can be fomites for transmission of virus

29 Slurry application risk: Proof of concept

30 PRRS Immunology Vaccines New vaccine in the market Modified Live Products PRRS MLV Boehringer Ingelheim PRRS ATP Boehringer Ingelheim Fostera PRRS Pfizer Killed Products MJ PRRS Sirrah Autogenous

31 PRRS Vaccines Ongoing research on efficacy Have been proven scientifically to: Reduce lung lesions Reduce duration of viremia Reduce shedding of virus via aerosols Improve certain production parameters

32 Load%close%homogenize0to0eliminate0PRRSv0 from0acutely0infected0breeding0herds.0 0 Part01:0>me0to0neg0pig0produc>on0(TTNP)0 Part02:0produc>on0analysis0(TTBP/total0loss)0 Part03:0nega>ve0herd0(factors,0gilt0mgmt)0 Linhares D, DVM, MBA; Cano JP, DVM, PhD; Torremorell M, DVM, PhD; Morrison R, DVM, MBA, PhD. 10

33 TTNP0probability0 Treatment:(LVI(vs(MLV(

34 Prior(PRRSvBinfec9on:(yes(vs(no( 80

35 Vaccinated0herds0had0significantly0less0 total0loss0

36 G(e(n(e(r(a(l((((((S(u(m(m(a(r(y( LVI(herds(reached( nega9ve(sooner( MLV(herds(had(less( total(loss( Median(9meBtoBnega9ve(was((~(210(days( Herds(with(prior(PRRSv(infec9on(reached(nega9ve(sooner,( recovered(produc9on(faster(and(had(less(total(loss( Farms(with(up(to(3(monthly(PCRBnega9ve(tests(with( produc9on(levels( in(control (might(s9ll(have(prrsv( circula9ng(at(low(prevalence(levels( PRRSv(monitoring(must(be(done(over(9me(

37 Data Provided from Steve Tousignant, Bob Morrison Funding from National Pork Board

38 Data Provided from Steve Tousignant, Bob Morrison Funding from National Pork Board

39 Summary Comments As an industry, we need to continue to come together to prevent the spread of PRRS We need to utilize proven scientific knowledge, not just what might work/seems to work We need to continue to research disease movement, immunology, genetics, etc. We (as an industry) have cut many corners to decrease cost that are causing problems Down time Sanitation Etc

40 Acknowledgements Daniel Linhares Steve Tousignant Dr. Bob Morrison Dr. Scott Dee Pipestone Research Committee Dr. Scott Dee, Dr. Joel Nerem, Dr. Barry Kerkaert, Dr. Luke Minion, Dan Hanson

MINNESOTA VOLUNTARY PRRS ELIMINATION PROJECT. Pork Lenders Meeting July 29, 2011 Dave Wright, D.V.M.

MINNESOTA VOLUNTARY PRRS ELIMINATION PROJECT Pork Lenders Meeting July 29, 2011 Dave Wright, D.V.M. Coordinator Minnesota Voluntary Regional PRRS Elimination Project N212 Funding USDA APHIS PRRS CAP AASV