A Feasibility Study of Roadside Oral Fluid Drug Testing, December ...
Oral Fluid Testing: Field Applications and Work In Progress
54
Oral fluid testing: Field applications and work in progress J Zimmerman, J Prickett. Iowa State University
description
Oral Fluid Testing: Field Applications and Work In Progress - Dr. Jeff Zimmerman, D.V.M., Ph.D. and John Prickett Iowa State University, at the Boehringer Ingelheim Vetmedica, Inc. Swine Health Seminar, August 15, 2009, Carolina Beach, North Carolina, USA.
Transcript of Oral Fluid Testing: Field Applications and Work In Progress
Oral fluid testing:Field applications and work in progress
J Zimmerman, J Prickett.Iowa State University
Big Picture
Morrison et al. 2008.Regional control ofPRRS in Minnesota
Morrison et al. 2008.Regional control ofPRRS in Minnesota
= field data
Morrison et al. 2008.Regional control ofPRRS in Minnesota
= field data
… and productionmanagement
Example 1. PredictoutbreaksGiven the same virus,increasing population sizeresults in …
1. Endemicity (no herd immunity)2. Continual cases w/ periodicoutbreaks3. Shorter inter-epidemic intervals4. Larger outbreaks at moreregular intervalsHaggett. 2000. GeographicalStructure of Epidemics
Age- and source-matchednegative controls. Highlyuniform body size
PRRSV = non-uniform size
Example 2. Predict performance
0
50
100
150
200
250
300
350
400
450
Day
42
Day
56
Day
70
Day
84
Day
98
Day
112
Day
119
Day
133
Day
147
Day
161
Day
175
Day
189
Days post-infection
Po
un
ds positive
negative
Difference
Example 2. Predict performance
PRRSV unevenand 2 weeks late
Morrison et al. 2008.Regional control ofPRRS in Minnesota
= field data
… and productionmanagement
• Wean-finish mortality 0.2% per year 1996-2005• Global trend. Not linked w/ PCV2.• Concurrent increase in health costs
Mortality RatesInching Upward. Nov15, 2006
Is the current infrastructure working?
• We are big and complex …
Is the current infrastructure working?
Wayne Spencer. Networkanalysis of the role of pigmovements in area spreadof PRRSV. 2007 Internat’lPRRS Symposium
Morrison et al. 2008.Regional control of PRRS inMinnesota
Is the current infrastructure working?
Images from WHO/CDS/2005.28
Morrison et al. 2008.Regional control ofPRRS in Minnesota
= field data
… and productionmanagement
= YES!!
Morrison et al. 2008.Regional control ofPRRS in Minnesota
= field data
… and productionmanagement
= producer driven, cheap, efficient
Morrison et al. 2008.Regional control ofPRRS in Minnesota
= field data
… and productionmanagement
= it is up to us
How different would thingshave been IF we had ourown spokesman and ourown data on 2009H1N1?
– Dollar-wise?– Public relations-wise?
The real storyon 2009 H1N1
…
To control disease, optimize productivity,and protect our industry, we need cheap,plentiful, current data on infectious agents
Big Picture Conclusions
Oral fluid testing:Field applications - human
• 1988. Rational programme for screening travelersfor antibodies to hepatitis A. Lancet 1(8600):1447.
• 1992. Comparison of saliva and serum for HIVsurveillance in developing countries. Lancet 340: 1496
• 1994. HIV surveillance by testing saliva frominjecting drug users: a national study in NewZealand. J Epidemiol Community Health 48:55
• 1994. The use of oral fluid for hepatitis C antibodyscreening. Am J Gastroenterol 89:2025.
Field applications
• 1997. Surveillance of measles in England andWales: implications of a national saliva testingprogram. Bull World Health Organ 75:515
• 2001. Has oral fluid the potential to replace serumfor the evaluation of population immunity levels? Astudy of measles, rubella, and hepatitis B in ruralEthiopia. Bull World Health Organ 79:588.
Field applications
• 2004. A population-based seroprevalence study ofhepatitis A virus using oral fluid in England and Wales.Am J Epidemiol 159:786. Mail-in population survey.5,500 samples collected.
• 2007. Participant-collected, mail-delivered oral fluidspecimens can replace traditional serosurvey: ademonstration-of-feasibility survey of hepatitis A virus-specific antibodies in adults. Can J Public Health 98:37
• 2009. Feasibility of collecting oral fluid samples in thehome to determine seroprevalence of infections. EpidemiolInfect 137:211. Mailed in samples received from 11,698children.
Field applications
• 2005 - 10 NY STD clinics implement oral fluidtesting = 40% increase in number tested
• Specificity 99.8%• Sensitivity ~99%• March 2005 – May 2008
– 166,058 oral fluid HIV tests– 442 (0.27%) false positive rate
2009. Ann Emerg Med 53:151
Field applications
OraQuick® Advance Rapid HIV-1/2 Antibody Test
Summary and conclusions• Lots of research on oral fluid diagnostics in humans
beginning as early as 1909• Focus primarily on antibody detection• Widely used in surveillance
– Especially HIV– Large mail-in surveys. Self-collected samples
sent via mail = lots of cheap data• Tests need to be optimized to the specimen
– Some tests better than others
Oral fluid testing:Field applications – wean-to-finish pigs
Summary of PCR field data10 sites x 6 pens per site (n = 600)
1100 head wean-finish barns
Our experience in the field … - Samples collected by site personnel - 10 sites x 6 pens x 10 samples per site = 600 samples - Supplies stored on-site
Rope, coolers, felt-tipped pens, addresslabels, etc. - “How to Collect” poster displayed at each site - Just one set of samples from one barn arrived late
OF sampling in 1,100head wean-finishbarns
Summary of field data: 10 sites x 6 pens per site
Sites show different patterns of infection
Summary of field data: 10 sites x 6 pens per site
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
10 wean-finish sites monitored using oral fluids
Torque teno virus PCR testing [work in progress]
Among 600 oral fluid samples, - 25 of 121 (21%) PCR-positive for TTV-1 - 97 of 121 (80%) PCR-positive for TTV-2 - 23 of 25 TTV-1 samples also positive for TTV-2
10 wean-finish sites monitored using oral fluids
FACT:Impossible to reproduce this study or theseinteractions under experimental conditions
10 wean-finish sites monitored using oral fluids
Observations …. This stuff is not in the books- Pigs arrive at 3 weeks of age shedding PCV2, PRRSV, SIV
10 wean-finish sites monitored using oral fluids
Observations …. This stuff is not in the books- Pigs arrive at 3 weeks of age shedding PCV2, PRRSV, SIV- Sites are in the same system, but very different patterns
• Duration of PCV2, PRRSV, and SIV shedding highlyvariable • Repeat episodes of virus circulation(PRRSV and/or SIV)
• Prolonged PCV2 circulation post-vaccination
10 wean-finish sites monitored using oral fluids
Observations …. This stuff is not in the books- Pigs arrive at 3 weeks of age shedding PCV2, PRRSV, SIV- Sites are in the same system, but very different patterns
• Duration of PCV2, PRRSV, and SIV shedding highlyvariable • Repeat episodes of virus circulation(PRRSV and/or SIV)
• Prolonged PCV2 circulation post-vaccination- Some PCV2 vaccination protocols work better than others!
10 wean-finish sites monitored using oral fluids
Observations …. This stuff is not in the books- Pigs arrive at 3 weeks of age shedding PCV2, PRRSV, SIV- Sites are in the same system, but very different patterns
• Duration of PCV2, PRRSV, and SIV shedding highlyvariable • Repeat episodes of virus circulation(PRRSV and/or SIV)
• Prolonged PCV2 circulation post-vaccination- Some PCV2 vaccination protocols work better than others!- Economic / productivity effects? [work in progress]
10 wean-finish sites monitored using oral fluids
Applications?- Monitor negative status populations (esp boar studs, sow herds)- Evaluate vaccine protocols and vaccine efficacy- Monitor vaccine compliance- Monitor controlled exposure- Monitor antibiotic withdrawal [idea in progress]- Predict disease losses- Predict growth rates and uniformity- Plan, time, and test interventions
Sample number and frequency?
Sample number and frequency?
What’s in the pipeline?
Research in progress
• Antibody test development for oral fluids– KSU (PCV2)– ISU (PCV2, PRRSV, SIV, M hyo)– SDSU (PRRSV)
• PCR optimization (ISU)• Oral fluid sampling
from sows andboars (PIC, UM, ISU)
Research in progress
• Sample collection from boars expands thepossible applications to studs and sowherds– Most boars are cooperators– Sample recovery is easy– And more welfare-friendly than bleeding
Summary
Quick,easy,cheapto collect►
▼ PCR detection of SIV, PCV2, PRRSV. Others?
▼ PRRSV and PCV2 ELISA antibody assays.Others in progress ..
Prickett et al., 2008. Detection of PRRSV infection in porcine oral fluid samples. J Vet Diagn Invest 20:156-163. Prickett et al., 2008. Oral-fluid samples for surveillance of commercial growing pigs for PRRSV and PCV2 infections. JSHAP 16(2):86-91.Hoffman P, Prickett J, et al., 2008. Implementation and validation of swine oral fluid collection in a commercial system. 38th Annual Meeting of the AASV. San Diego, California, pp. 301-302.
Surveillance of commercial swine units using oral fluid samples
ORAL FLUID
• Lower cost than serum• Lower tech than serum• Lower sample numbers
than serum• Some tests available
and additional testsshould be able in 2010(research in progress)
• Barn/site level testing(not pig level) - willrequire a paradigm shift
• PCRs are too expensive• Antibody tests need to
be optimized• Much data missing• New and scary
CONSPROS
Acknowledgements and Thanks
• John Prickett, ApisitKittawornratt, Jeremy Johnson,Trevor Schwartz, Dan
• Drs. Rodger Main, JohnJohnson, SheelaRamamoorthy, Erin Strait, K-JYoon, Wayne Chittick, KentSchwartz, Chong Wang - IowaState University
• Drs. Bob Morrison, MikeMurtaugh - University ofMinnesota
• Dr. Ramon Molina - ITSON,Sonora Mexico
• Dr. Mark Engle - PIC
• Pat Hoffmann, Ann and ErnieKurtz - Murphy-Brown LLCWestern Operations
• Drs. Michael Roof & ReidPhilips - Boehringer IngelhemVetmedica, Inc.
• Drs. Steve Sornsen & RonWhite - Pfizer, Inc.
• Dr. Bob Rowland - KansasState University
• USDA PRRS CAP
