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Robert E, Goonewardene K, El Kanoa I, Hochman O, Nfon C, Ambagala A. Oral Fluids for the Early Detection of Classical Swine Fever in Commercial Level Pig Pens. Viruses 2024; 16:318. [PMID: 38543685 PMCID: PMC10974009 DOI: 10.3390/v16030318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 02/15/2024] [Accepted: 02/17/2024] [Indexed: 05/23/2024] Open
Abstract
The early detection of classical swine fever (CSF) remains a key challenge, especially when outbreaks are caused by moderate and low-virulent CSF virus (CSFV) strains. Oral fluid is a reliable and cost-effective sample type that is regularly surveilled for endemic diseases in commercial pig herds in North America. Here, we explored the possibility of utilizing oral fluids for the early detection of CSFV incursions in commercial-size pig pens using two independent experiments. In the first experiment, a seeder pig infected with the moderately-virulent CSFV Pinillos strain was used, and in the second experiment, a seeder pig infected with the highly-virulent CSFV Koslov strain was used. Pen-based oral fluid samples were collected daily and individual samples (whole blood, swabs) every other day. All samples were tested by a CSFV-specific real-time RT-PCR assay. CSFV genomic material was detected in oral fluids on the seventh and fourth day post-introduction of the seeder pig into the pen, in the first and second experiments, respectively. In both experiments, oral fluids tested positive before the contact pigs developed viremia, and with no apparent sick pigs in the pen. These results indicate that pen-based oral fluids are a reliable and convenient sample type for the early detection of CSF, and therefore, can be used to supplement the ongoing CSF surveillance activities in North America.
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Affiliation(s)
- Erin Robert
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, MB R3E 0W2, Canada
| | - Kalhari Goonewardene
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Ian El Kanoa
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Orie Hochman
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Charles Nfon
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Aruna Ambagala
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, MB R3E 0W2, Canada
- Department of Animal Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada
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Dynamics of Serological and Mucosal Antibody Responses against African Swine Fever Viruses in Experimentally Infected Pigs. Transbound Emerg Dis 2023. [DOI: 10.1155/2023/9959847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
African swine fever virus (ASFV) is a lethal swine pathogen, and there is no effective vaccine or treatment available for ASFV infection. Recently, the occurrence of ASFV genotype I and genotype II natural mutants that manifest as subacute, longer-incubation, or persistent infections poses threats to preventing ASFV infection. The dynamics of antibody responses to ASFV are still completely unrevealed, especially the secretion of mucosal antibodies in oral fluid. Here, a systematic analysis was performed of serological and mucosal antibody secretion against 6 ASFV antigens after direct or indirect infection with four different ASFV strains or genotypes, namely, the field virulent genotype II isolate ASFV HLJ/18, the artificially attenuated genotype II strain HLJ/18-7GD, the naturally attenuated genotype II isolate HLJ/HRB1/20, and genotype I isolate SD/DY-I/21. Severe clinical signs of HLJ/18 infection were observed in pigs from 4 days postinoculation. However, no clinical signs were observed in HLJ/18-7GD-infected pigs. The contact pigs cohoused with the pigs intramuscularly infected with the isolate SD/DY-I/21 or HLJ/HRB1/20 only showed chronic clinical signs. Interestingly, the oral fluid sIgA responses to all the selected antigens were significantly stronger and earlier than the serum IgG responses in both HLJ/18- and HLJ/18-7GD-challenged pigs. Although significant fluctuations and individual differences appeared in oral swab sIgA responses in the contact transmission group, they were earlier than the corresponding serological IgG responses. Moreover, according to the comparative analysis of the three infection groups, P54 was proposed to be a dominant target for serological IgG diagnosis, while P30, CD2v, P54, P22, and P10 were more advantageous as mucosal sIgA diagnosis targets. These results highlight the important role of mucosal antibodies in the early diagnosis of ASFV infection and can provide references to screen appropriate targets for ASFV detection.
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Self-administration of a Salmonella vaccine by domestic pigs. Sci Rep 2023; 13:2972. [PMID: 36806288 PMCID: PMC9941462 DOI: 10.1038/s41598-023-29987-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Hand vaccinating is time consuming and inefficient. Oral vaccines delivered by drenching are less likely to be used due to a lack of labor on farms. Current environmental enrichment (EE) technologies do not allow pigs to express certain natural behaviors such as rooting and getting a reward. We developed a sprayer so that domestic pigs can self-apply any liquid. By adding an attractant (pig maternal pheromone), the use of EE devices by individual pigs can be increased. In this study, we used a Salmonella oral vaccine to evaluate efficacy of three delivery methods: (1) Control, no vaccine, (2) hand drenching as labeled, and (3) self-administration by this EE rooting device. All pigs sprayed themselves within 80 min of exposure to the EE device. While control pigs had little or no Salmonella serum and oral fluid IgG or IgA, hand-drenched and self-vaccinated pigs built similar levels of both serum and oral fluid IgA and IgG. We conclude we were able to significantly reduce human labor needed and achieved 100% efficacy in eliciting a serologic response when pigs self-administered a Salmonella vaccine. This technology could benefit commercial pig production while providing an enriched behavioral environment. Self-vaccination could also assist in control or immunization of feral swine and improve domestic pig health and food safety.
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den Hartog G, Vos ERA, van den Hoogen LL, van Boven M, Schepp RM, Smits G, van Vliet J, Woudstra L, Wijmenga-Monsuur AJ, van Hagen CCE, Sanders EAM, de Melker HE, van der Klis FRM, van Binnendijk RS. Persistence of Antibodies to Severe Acute Respiratory Syndrome Coronavirus 2 in Relation to Symptoms in a Nationwide Prospective Study. Clin Infect Dis 2021; 73:2155-2162. [PMID: 33624751 PMCID: PMC7929058 DOI: 10.1093/cid/ciab172] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Assessing the duration of immunity following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a first priority to gauge the degree of protection following infection. Such knowledge is lacking, especially in the general population. Here, we studied changes in immunoglobulin isotype seropositivity and immunoglobulin G (IgG) binding strength of SARS-CoV-2-specific serum antibodies up to 7 months following onset of symptoms in a nationwide sample. METHODS Participants from a prospective representative serological study in the Netherlands were included based on IgG seroconversion to the spike S1 protein of SARS-CoV-2 (N = 353), with up to 3 consecutive serum samples per seroconverted participant (N = 738). Immunoglobulin M (IgM), immunoglobulin A (IgA), and IgG antibody concentrations to S1, and increase in IgG avidity in relation to time since onset of disease symptoms, were determined. RESULTS While SARS-CoV-2-specific IgM and IgA antibodies declined rapidly after the first month after disease onset, specific IgG was still present in 92% (95% confidence interval [CI], 89%-95%) of the participants after 7 months. The estimated 2-fold decrease of IgG antibodies was 158 days (95% CI, 136-189 days). Concentrations were sustained better in persons reporting significant symptoms compared to asymptomatic persons or those with mild upper respiratory complaints only. Similarly, avidity of IgG antibodies for symptomatic persons showed a steeper increase over time compared with persons with mild or no symptoms (P = .022). CONCLUSIONS SARS-CoV-2-specific IgG antibodies persist and show increasing avidity over time, indicative of underlying immune maturation. These data support development of immune memory against SARS-CoV-2, providing insight into protection of the general unvaccinated part of the population. CLINICAL TRIALS REGISTRATION NL8473 (the Dutch trial registry).
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Affiliation(s)
- Gerco den Hartog
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Eric R A Vos
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
- Centre for Infectious Diseases, Epidemiology and Surveillance, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Lotus L van den Hoogen
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Michiel van Boven
- Centre for Infectious Diseases, Epidemiology and Surveillance, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Rutger M Schepp
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Gaby Smits
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Jeffrey van Vliet
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Linde Woudstra
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Alienke J Wijmenga-Monsuur
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Cheyenne C E van Hagen
- Centre for Infectious Diseases, Epidemiology and Surveillance, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Elisabeth A M Sanders
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Hester E de Melker
- Centre for Infectious Diseases, Epidemiology and Surveillance, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Fiona R M van der Klis
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Robert S van Binnendijk
- Centre for Immunology of Infectious Diseases and Vaccines, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
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Henao-Diaz A, Giménez-Lirola L, Baum DH, Zimmerman J. Guidelines for oral fluid-based surveillance of viral pathogens in swine. Porcine Health Manag 2020; 6:28. [PMID: 33082999 PMCID: PMC7569198 DOI: 10.1186/s40813-020-00168-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 08/26/2020] [Indexed: 12/18/2022] Open
Abstract
Recent decades have seen both rapid growth and extensive consolidation in swine production. As a collateral effect, these changes have exacerbated the circulation of viruses and challenged our ability to prevent, control, and/or eliminate impactful swine diseases. Recent pandemic events in human and animal health, e.g., SARS-CoV-2 and African swine fever virus, highlight the fact that clinical observations are too slow and inaccurate to form the basis for effective health management decisions: systematic processes that provide timely, reliable data are required. Oral fluid-based surveillance reflects the adaptation of conventional testing methods to an alternative diagnostic specimen. The routine use of oral fluids in commercial farms for PRRSV and PCV2 surveillance was first proposed in 2008 as an efficient and practical improvement on individual pig sampling. Subsequent research expanded on this initial report to include the detection of ≥23 swine viral pathogens and the implementation of oral fluid-based surveillance in large swine populations (> 12,000 pigs). Herein we compile the current information regarding oral fluid collection methods, testing, and surveillance applications in swine production.
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Affiliation(s)
- Alexandra Henao-Diaz
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Veterinary Medical Research Institute, Iowa State University, Ames, Iowa 50011 USA
| | - Luis Giménez-Lirola
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Veterinary Medical Research Institute, Iowa State University, Ames, Iowa 50011 USA
| | - David H Baum
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Veterinary Medical Research Institute, Iowa State University, Ames, Iowa 50011 USA
| | - Jeffrey Zimmerman
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Veterinary Medical Research Institute, Iowa State University, Ames, Iowa 50011 USA
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6
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Atkinson BM, Bearson BL, Loving CL, Zimmerman JJ, Kich JD, Bearson SMD. Detection of Salmonella-specific antibody in swine oral fluids. Porcine Health Manag 2019; 5:29. [PMID: 31890253 PMCID: PMC6915926 DOI: 10.1186/s40813-019-0136-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 11/25/2019] [Indexed: 01/01/2023] Open
Abstract
Salmonella is a leading cause of bacterial foodborne-related illness and pork products are a food-associated source. With > 50% of U.S. swine herds testing positive for Salmonella, asymptomatic carrier pigs that shed Salmonella in their feces are a food safety and environmental contamination issue. Herd level surveillance of Salmonella shedding status is useful, but collection of feces and culture methods for Salmonella detection are laborious and time-consuming. Surveillance for Salmonella-exposure through detection of Salmonella-specific serum antibody is a reliable method, but presents labor and animal-welfare issues. Oral fluids are a reliable, antemortem sample with proven utility for surveillance in the swine industry. We tested oral fluid samples as a potential non-invasive, repeatable sample type for the presence of Salmonella-specific antibodies. An indirect enzyme-linked immunosorbent assay (ELISA) detected anti-Salmonella IgG, IgM, and predominantly IgA in oral fluids from Salmonella enterica serovar Typhimurium-exposed pigs. Furthermore, with minor modifications, a commercial ELISA-based kit also detected Salmonella-specific antibodies in oral fluids. Collectively, oral fluids may serve as a prospective surveillance tool for herd level monitoring of Salmonella exposure.
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Affiliation(s)
- Briony M Atkinson
- 1Food Safety and Enteric Pathogens Research Unit, USDA, ARS, National Animal Disease Center, 1920 Dayton Ave, Room 1403, Ames, IA 50010 United States
| | - Bradley L Bearson
- 2Agroecosystems Management Research Unit, USDA, ARS, National Laboratory for Agriculture and the Environment, Ames, IA United States
| | - Crystal L Loving
- 1Food Safety and Enteric Pathogens Research Unit, USDA, ARS, National Animal Disease Center, 1920 Dayton Ave, Room 1403, Ames, IA 50010 United States
| | - Jeffrey J Zimmerman
- 3College of Veterinary Medicine, Iowa State University, Ames, IA United States
| | - Jalusa D Kich
- 1Food Safety and Enteric Pathogens Research Unit, USDA, ARS, National Animal Disease Center, 1920 Dayton Ave, Room 1403, Ames, IA 50010 United States.,Embrapa Swine and Poultry, Concórdia, SC Brazil
| | - Shawn M D Bearson
- 1Food Safety and Enteric Pathogens Research Unit, USDA, ARS, National Animal Disease Center, 1920 Dayton Ave, Room 1403, Ames, IA 50010 United States
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7
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Almeida MN, Rotto H, Schneider P, Robb C, Zimmerman JJ, Holtkamp DJ, Rademacher CJ, Linhares DCL. Collecting oral fluid samples from due-to-wean litters. Prev Vet Med 2019; 174:104810. [PMID: 31756669 DOI: 10.1016/j.prevetmed.2019.104810] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 10/10/2019] [Accepted: 10/22/2019] [Indexed: 11/17/2022]
Abstract
Oral fluids are a common diagnostic sample in group-housed nursery, grow-finish, and adult swine. Although oral fluids from due-to-wean litters could be a valuable tool in monitoring pathogens and predicting the health status of pig populations post-weaning, it is generally not done because of inconsistent success in sample collection. The objective of this study was to determine the optimum procedure for collecting oral fluid samples from due-to-wean litters. Successful collection of oral fluids from due-to-wean litters using "Litter Oral Fluid" (LOF) or "Family Oral Fluid" (FOF) sampling techniques were compared in 4 phases involving 920 attempts to collect oral fluids. Phase 1 testing showed that prior exposure to a rope improved the success rates of both LOF (33.4%) and FOF (16.4%) techniques. Phase 2 determined that longer access to the rope (4 h vs 30 min) did not improve the success rate for either LOF or FOF. Phase 3 evaluated the effect of attractants and found that one (Baby Pig Restart®) improved the success rate when used with the FOF technique. Phase 4 compared the success rates of "optimized LOF" (litters previously trained) vs "optimized FOF" (litter previously trained and rope treated with Baby Pig Restart®) vs standard FOF. No difference was found between the FOF-based techniques, but both were superior to the "optimized LOF" technique. Thus, FOF-based procedures provided a significantly higher probability of collecting oral fluids from due-to-wean litters (mean success rate 84.9%, range 70% to 92%) when compared to LOF-based methods (mean success rate 24.1%, range 16.5% to 32.2%).
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Affiliation(s)
- M N Almeida
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - H Rotto
- Innovative Agriculture Solutions, LLC, Ames, IA, United States
| | - P Schneider
- Innovative Agriculture Solutions, LLC, Ames, IA, United States
| | - C Robb
- Innovative Agriculture Solutions, LLC, Ames, IA, United States
| | - J J Zimmerman
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - D J Holtkamp
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - C J Rademacher
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - D C L Linhares
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States.
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Popescu LN, Panyasing Y, Giménez-Lirola L, Zimmerman J, Rowland RRR. E2 and E rns isotype-specific antibody responses in serum and oral fluid after infection with classical swine fever virus (CSFV). Vet Microbiol 2019; 235:265-269. [PMID: 31383311 DOI: 10.1016/j.vetmic.2019.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 07/01/2019] [Accepted: 07/07/2019] [Indexed: 11/29/2022]
Abstract
Oral fluid sampling for the detection of classical swine fever virus infection provides a relatively inexpensive method for conducting active CSF surveillance. The purpose of this study was to detect CSFV nucleic acid and antibody in serum and oral fluid samples in a group of 10 pigs infected with the moderate CSFV strain, Paderborn. Based on clinical signs, outcome, and other results, pigs were placed into one of three disease outcome groups; Acute, Chronic and Recovered. Oral fluid and serum samples were analyzed for the presence of CSFV nucleic acid along with E2 and Erns surface protein-specific IgM, IgG and IgA responses. The results were summarized into a timeline of detection events beginning with the appearance of E2-IgM in serum (3 DPI) followed by CSFV nucleic acid in serum (6 DPI), CSFV nucleic acid in oral fluid (8 DPI), E2-IgG in serum (20 DPI), and E2-IgG in oral fluid (24 DPI). The results show that a combination of molecular and serological analyses of oral fluid can be incorporated into CSF surveillance.
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Affiliation(s)
- Luca N Popescu
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary, Kansas State University, Manhattan, KS, 66506, USA
| | - Yaowalak Panyasing
- Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Luis Giménez-Lirola
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary, Medicine, Iowa State University, Ames, IA, 50011, USA
| | - Jeff Zimmerman
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary, Medicine, Iowa State University, Ames, IA, 50011, USA
| | - Raymond R R Rowland
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary, Kansas State University, Manhattan, KS, 66506, USA.
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Holzer B, Martini V, Edmans M, Tchilian E. T and B Cell Immune Responses to Influenza Viruses in Pigs. Front Immunol 2019; 10:98. [PMID: 30804933 PMCID: PMC6371849 DOI: 10.3389/fimmu.2019.00098] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 01/14/2019] [Indexed: 01/31/2023] Open
Abstract
Influenza viruses are an ongoing threat to humans and are endemic in pigs, causing considerable economic losses to farmers. Pigs are also a source of new viruses potentially capable of initiating human pandemics. Many tools including monoclonal antibodies, recombinant cytokines and chemokines, gene probes, tetramers, and inbred pigs allow refined analysis of immune responses against influenza. Recent advances in understanding of the pig innate system indicate that it shares many features with that of humans, although there is a larger gamma delta component. The fine specificity and mechanisms of cross-protective T cell immunity have yet to be fully defined, although it is clear that the local immune response is important. The repertoire of pig antibody response to influenza has not been thoroughly explored. Here we review current understanding of adaptive immune responses against influenza in pigs and the use of the pig as a model to study human disease.
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Affiliation(s)
- Barbara Holzer
- Department of Mucosal Immunology, The Pirbright Institute (BBSRC), Pirbright, United Kingdom
| | - Veronica Martini
- Department of Mucosal Immunology, The Pirbright Institute (BBSRC), Pirbright, United Kingdom
| | - Matthew Edmans
- Department of Mucosal Immunology, The Pirbright Institute (BBSRC), Pirbright, United Kingdom
| | - Elma Tchilian
- Department of Mucosal Immunology, The Pirbright Institute (BBSRC), Pirbright, United Kingdom
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10
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Detection of classical swine fever virus (CSFV) E2 and E rns antibody (IgG, IgA) in oral fluid specimens from inoculated (ALD strain) or vaccinated (LOM strain) pigs. Vet Microbiol 2018; 224:70-77. [PMID: 30269793 DOI: 10.1016/j.vetmic.2018.08.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/22/2018] [Accepted: 08/24/2018] [Indexed: 11/22/2022]
Abstract
The objective of this study was to describe oral fluid and serum antibody (IgG, IgA) responses against classical swine fever virus (CSFV) E2 and Erns proteins in pigs (n = 60) inoculated with a moderately virulent field strain (ALD, n = 30) or a modified live virus vaccine strain (LOM, n = 30). Oral fluid (n = 1391) and serum (n = 591) samples were collected from individually-housed pigs between day post inoculation (DPI) -14 to 28. Testing revealed the synchronous appearance of E2- and Erns-specific IgG and IgA antibodies in serum and oral fluids over time, with E2 and Erns IgG ELISAs providing better diagnostic performance than the IgA ELISAs. Overall the data suggest the feasibility of large-scale, cost-effective screening of populations for CSFV using oral fluid samples. Given the historic issues of cross-reactivity among pestiviruses, future research should focus on the development of CSFV-specific testing platforms for the detection of E2 and/or Erns IgG in oral fluid, ideally to be used in combination with DIVA vaccines.
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Newcastle Disease Virus-Based Vectored Vaccine against Poliomyelitis. J Virol 2018; 92:JVI.00976-18. [PMID: 29925653 DOI: 10.1128/jvi.00976-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 06/06/2018] [Indexed: 12/28/2022] Open
Abstract
The poliovirus eradication initiative has spawned global immunization infrastructure and dramatically decreased the prevalence of the disease, yet the original virus eradication goal has not been met. The suboptimal properties of the existing vaccines are among the major reasons why the program has repeatedly missed eradication deadlines. Oral live poliovirus vaccine (OPV), while affordable and effective, occasionally causes the disease in the primary recipients, and the attenuated viruses rapidly regain virulence and can cause poliomyelitis outbreaks. Inactivated poliovirus vaccine (IPV) is safe but expensive and does not induce the mucosal immunity necessary to interrupt virus transmission. While the need for a better vaccine is widely recognized, current efforts are focused largely on improvements to the OPV or IPV, which are still beset by the fundamental drawbacks of the original products. Here we demonstrate a different design of an antipoliovirus vaccine based on in situ production of virus-like particles (VLPs). The poliovirus capsid protein precursor, together with a protease required for its processing, are expressed from a Newcastle disease virus (NDV) vector, a negative-strand RNA virus with mucosal tropism. In this system, poliovirus VLPs are produced in the cells of vaccine recipients and are presented to their immune systems in the context of active replication of NDV, which serves as a natural adjuvant. Intranasal administration of the vectored vaccine to guinea pigs induced strong neutralizing systemic and mucosal antibody responses. Thus, the vectored poliovirus vaccine combines the affordability and efficiency of a live vaccine with absolute safety, since no full-length poliovirus genome is present at any stage of the vaccine life cycle.IMPORTANCE A new, safe, and effective vaccine against poliovirus is urgently needed not only to complete the eradication of the virus but also to be used in the future to prevent possible virus reemergence in a postpolio world. Currently, new formulations of the oral vaccine, as well as improvements to the inactivated vaccine, are being explored. In this study, we designed a viral vector with mucosal tropism that expresses poliovirus capsid proteins. Thus, poliovirus VLPs are produced in vivo, in the cells of a vaccine recipient, and are presented to the immune system in the context of vector virus replication, stimulating the development of systemic and mucosal immune responses. Such an approach allows the development of an affordable and safe vaccine that does not rely on the full-length poliovirus genome at any stage.
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12
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Almeida MN, Zimmerman JJ, Wang C, Linhares DCL. Assessment of abattoir based monitoring of PRRSV using oral fluids. Prev Vet Med 2018; 158:137-145. [PMID: 30220387 DOI: 10.1016/j.prevetmed.2018.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 07/12/2018] [Accepted: 08/07/2018] [Indexed: 02/06/2023]
Abstract
Various porcine reproductive and respiratory syndrome virus (PRRSV) regional elimination projects have been implemented in the U.S., but none have yet succeeded. In part, this reflects the need for efficient methods to monitor over time the progress of PRRSV status of participating herds. This study assessed the feasibility of monitoring PRRSV using oral fluids collected at the abattoir. A total of 36 pig lots were included in the study. On-farm oral fluid (n = 10) and serum (n = 10) collected within two days of shipment to the abattoir were used to establish the reference PRRSV status of the population. Oral fluids (n = 3 per lot) were successfully collected from 32 lots (89%) at the lairage. Three veterinary diagnostic laboratories (VDLs) tested the sera (VDL1 and VDL3: n = 316, VDL2: n = 315) and oral fluids (VDL1 and VDL3: n = 319, VDL2: n = 320) for PRRSV antibodies (ELISA) and RNA (rRT-PCR). Environmental samples (n = 64, 32 before and 32 after pigs were placed in lairage) were tested for PRRSV RNA at one VDL. All oral fluids (farm and abattoir) tested positive for PRRSV antibody at all VDLs. PRRSV positivity frequency on serum ranged from 92.4% to 94.6% among VDLs, with an overall agreement of 97.6%. RNA was detected on 1.3% to 1.9%, 8.1% to 17.7%, and 8.3% to 17.7% of sera, on-farm and abattoir oral fluids, respectively. Between-VDLs rRT-PCR agreement on sera and oral fluids (farm and abattoir) ranged from 97.8% to 99.0%, and 79.0% to 81.2%, respectively. Between-locations agreement of oral fluids varied from 31.3% to 50% depending on the VDL. This study reported the application of swine oral fluids collected at the abattoir for monitoring PRRSV, and describes the between-VDL agreement for PRRS testing of serum and oral fluid field samples.
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Affiliation(s)
- M N Almeida
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - J J Zimmerman
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - C Wang
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - D C L Linhares
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States.
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13
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Herd-level infectious disease surveillance of livestock populations using aggregate samples. Anim Health Res Rev 2018; 19:53-64. [PMID: 29779505 DOI: 10.1017/s1466252318000038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
All sectors of livestock production are in the process of shifting from small populations on many farms to large populations on fewer farms. A concurrent shift has occurred in the number of livestock moved across political boundaries. The unintended consequence of these changes has been the appearance of multifactorial diseases that are resistant to traditional methods of prevention and control. The need to understand complex animal health conditions mandates a shift toward the collection of longitudinal animal health data. Historically, collection of such data has frustrated and challenged animal health specialists. A promising trend in the evolution toward more efficient and effective livestock disease surveillance is the increased use of aggregate samples, e.g. bulk tank milk and oral fluid specimens. These sample types provide the means to monitor disease, estimate herd prevalence, and evaluate spatiotemporal trends in disease distribution. Thus, this article provides an overview of the use of bulk tank milk and pen-based oral fluids in the surveillance of livestock populations for infectious diseases.
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14
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González W, Giménez-Lirola LG, Holmes A, Lizano S, Goodell C, Poonsuk K, Sitthicharoenchai P, Sun Y, Zimmerman J. Detection of Actinobacillus Pleuropneumoniae ApxIV Toxin Antibody in Serum and Oral Fluid Specimens from Pigs Inoculated Under Experimental Conditions. J Vet Res 2017; 61:163-171. [PMID: 29978069 PMCID: PMC5894388 DOI: 10.1515/jvetres-2017-0021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 05/26/2017] [Indexed: 11/15/2022] Open
Abstract
Introduction The prevention and control of Actinobacillus pleuropneumoniae in commercial production settings is based on serological monitoring. Enzyme-linked immunosorbent assays (ELISAs) have been developed to detect specific antibodies against a variety of A. pleuropneumoniae antigens, including long-chain lipopolysaccharides (LPS) and the ApxIV toxin, a repeats-in-toxin (RTX) exotoxin unique to A. pleuropneumoniae and produced by all serovars. The objective of this study was to describe ApxIV antibody responses in serum and oral fluid of pigs. Material and Methods Four groups of pigs (six pigs per group) were inoculated with A. pleuropneumoniae serovars 1, 5, 7, or 12. Weekly serum samples and daily oral fluid samples were collected from individual pigs for 56 days post inoculation (DPI) and tested by LPS and ApxIV ELISAs. The ApxIV ELISA was run in three formats to detect immunlgobulins M, G, and A (IgM, IgG and IgA) while the LPS ELISA detected only IgG. Results All pigs inoculated with A. pleuropneumoniae serovars 1 and 7 were LPS ELISA serum antibody positive from DPI 14 to 56. A transient and weak LPS ELISA antibody response was observed in pigs inoculated with serovar 5 and a single antibody positive pig was observed in serovar 12 at ≥35 DPI. Notably, ApxIV serum and oral fluid antibody responses in pig inoculated with serovars 1 and 7 reflected the patterns observed for LPS antibody, albeit with a 14 to 21 day delay. Conclusion This work suggests that ELISAs based on ApxIV antibody detection in oral fluid samples could be effective in population monitoring for A. pleuropneumoniae.
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Affiliation(s)
- Wendy González
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | - Ashley Holmes
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | | | - Korakrit Poonsuk
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | - Yaxuan Sun
- College of Liberal Arts and Sciences, Iowa State University, Ames, IA, USA
| | - Jeffrey Zimmerman
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
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15
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Woonwong Y, Kedkovid R, Arunorat J, Sirisereewan C, Nedumpun T, Poonsuk K, Panyasing Y, Poolperm P, Boonsoongnern A, Thanawongnuwech R. Oral fluid samples used for PRRSV acclimatization program and sow performance monitoring in endemic PRRS-positive farms. Trop Anim Health Prod 2017; 50:291-298. [PMID: 28980168 DOI: 10.1007/s11250-017-1428-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 09/20/2017] [Indexed: 12/18/2022]
Abstract
An effective gilt acclimatization program is one of the most important management strategies for controlling porcine reproductive and respiratory syndrome virus (PRRSV) infection. Recently, oral fluid samples have been used as alternative diagnostic samples for various swine diseases. This study utilized oral fluids for PRRSV monitoring during the gilt acclimatization period in PRRSV endemic farms. The study was performed in two selected commercial breeding herds (farm A and farm B). PRRSV RNA and PRRSV-specific antibodies were monitored using oral fluid and serum samples. Sow performance parameters related to PRRSV infection were recorded and assessed. After PRRSV exposure during acclimatization, viral RNA was demonstrated in oral fluids from 1 to 10 weeks post-exposure (WPE). PRRSV RNA was detected in serum at 1 and 4 WPE in farm A and at 1, 4, 8, and 12 WPE in farm B. Prolonged viremia of gilts from farm B was possibly due to re-infection (within the herd) and later, reproductive problems were found in the breeding herd. The correlation of PRRSV RNA concentration in oral fluids and serum was evident. The S/P ratio values of PRRSV antibodies in oral fluid samples were higher and had similar patterns of antibody responses to the serum samples. The results suggest that the use of oral fluid samples for PRRSV monitoring during gilt acclimatization in endemic farms is effective, convenient, practical, and economical and would be most beneficial when used with other parameters.
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Affiliation(s)
- Yonlayong Woonwong
- Graduate Program in Veterinary Pathobiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand
| | - Roongtham Kedkovid
- Graduate Program in Veterinary Pathobiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand
| | - Jirapat Arunorat
- Graduate Program in Veterinary Pathobiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand
| | - Chaitawat Sirisereewan
- Graduate Program in Veterinary Pathobiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand
| | - Teerawut Nedumpun
- Inter-Department of Medical Microbiology, Graduate School, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand
| | - Korakrit Poonsuk
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, 50011, USA
| | - Yaowalak Panyasing
- Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand
| | - Pariwat Poolperm
- Department of Farm Resources and Production Medicine, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen, Nakhon Pathom, 73140, Thailand
| | - Alongkot Boonsoongnern
- Department of Farm Resources and Production Medicine, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen, Nakhon Pathom, 73140, Thailand.
| | - Roongroje Thanawongnuwech
- Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand.
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16
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Rotolo ML, Sun Y, Wang C, Giménez-Lirola L, Baum DH, Gauger PC, Harmon KM, Hoogland M, Main R, Zimmerman JJ. Sampling guidelines for oral fluid-based surveys of group-housed animals. Vet Microbiol 2017; 209:20-29. [PMID: 28284415 DOI: 10.1016/j.vetmic.2017.02.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 02/05/2017] [Accepted: 02/09/2017] [Indexed: 11/17/2022]
Abstract
Formulas and software for calculating sample size for surveys based on individual animal samples are readily available. However, sample size formulas are not available for oral fluids and other aggregate samples that are increasingly used in production settings. Therefore, the objective of this study was to develop sampling guidelines for oral fluid-based porcine reproductive and respiratory syndrome virus (PRRSV) surveys in commercial swine farms. Oral fluid samples were collected in 9 weekly samplings from all pens in 3 barns on one production site beginning shortly after placement of weaned pigs. Samples (n=972) were tested by real-time reverse-transcription PCR (RT-rtPCR) and the binary results analyzed using a piecewise exponential survival model for interval-censored, time-to-event data with misclassification. Thereafter, simulation studies were used to study the barn-level probability of PRRSV detection as a function of sample size, sample allocation (simple random sampling vs fixed spatial sampling), assay diagnostic sensitivity and specificity, and pen-level prevalence. These studies provided estimates of the probability of detection by sample size and within-barn prevalence. Detection using fixed spatial sampling was as good as, or better than, simple random sampling. Sampling multiple barns on a site increased the probability of detection with the number of barns sampled. These results are relevant to PRRSV control or elimination projects at the herd, regional, or national levels, but the results are also broadly applicable to contagious pathogens of swine for which oral fluid tests of equivalent performance are available.
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Affiliation(s)
- Marisa L Rotolo
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA.
| | - Yaxuan Sun
- Department of Statistics, College of Liberal Arts and Sciences, Iowa State University, Ames, IA, USA
| | - Chong Wang
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA; Department of Statistics, College of Liberal Arts and Sciences, Iowa State University, Ames, IA, USA
| | - Luis Giménez-Lirola
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - David H Baum
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Phillip C Gauger
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Karen M Harmon
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | - Rodger Main
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Jeffrey J Zimmerman
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
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17
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Gerber PF, Dawson L, Strugnell B, Burgess R, Brown H, Opriessnig T. Using oral fluids samples for indirect influenza A virus surveillance in farmed UK pigs. Vet Med Sci 2016; 3:3-12. [PMID: 29067204 PMCID: PMC5645835 DOI: 10.1002/vms3.51] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 10/06/2016] [Accepted: 11/01/2016] [Indexed: 12/03/2022] Open
Abstract
Influenza A virus (IAV) is economically important in pig production and has broad public health implications. In Europe, active IAV surveillance includes demonstration of antigen in nasal swabs and/or demonstration of antibodies in serum (SER) samples; however, collecting appropriate numbers of individual pig samples can be costly and labour‐intensive. The objective of this study was to compare the probability of detecting IAV antibody positive populations using SER versus oral fluid (OF) samples. Paired pen samples, one OF and 5–14 SER samples, were collected cross‐sectional or longitudinally. A commercial nucleoprotein (NP)‐based blocking ELISA was used to test 244 OF and 1004 SER samples from 123 pens each containing 20–540 pigs located in 27 UK herds. Overall, the IAV antibody detection rate was higher in SER samples compared to OFs under the study conditions. Pig age had a significant effect on the probability of detecting positive pens. For 3–9‐week‐old pigs the probability of detecting IAV antibody positive samples in a pen with 95% confidence intervals was 40% (23–60) for OF and 61% (0.37–0.80) for SER (P = 0.04), for 10–14‐week‐old pigs it was 19% (8–40) for OF and 93% (0.71–0.99) for SER (P < 0.01), and for 18–20‐week‐old pigs it was 67% (41–85) for OF and 81% (0.63–0.91) for SER (P = 0.05). Collecting more than one OF sample in pens with more than 25 less than 18‐week‐old pigs should be further investigated in the future to elucidate the suitability of OF for IAV surveillance in herds with large pen sizes.
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Affiliation(s)
- Priscilla F Gerber
- The Roslin Institute and The Royal (Dick) School of Veterinary StudiesUniversity of EdinburghMidlothianScotlandUK
| | - Lorna Dawson
- School of AgricultureFood and Rural DevelopmentNewcastle UniversityNewcastle upon TyneUK
| | - Ben Strugnell
- Evidence-based Veterinary Consultancy (EBVC) Ltd.Rural Enterprise CentreRedhillsPenrithCumbriaUK
| | - Robert Burgess
- Evidence-based Veterinary Consultancy (EBVC) Ltd.Rural Enterprise CentreRedhillsPenrithCumbriaUK
| | - Helen Brown
- The Roslin Institute and The Royal (Dick) School of Veterinary StudiesUniversity of EdinburghMidlothianScotlandUK
| | - Tanja Opriessnig
- The Roslin Institute and The Royal (Dick) School of Veterinary StudiesUniversity of EdinburghMidlothianScotlandUK.,Department of Veterinary Diagnostic and Production Animal MedicineIowa State UniversityAmesIowaUSA
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18
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Senthilkumaran C, Bittner H, Ambagala A, Lung O, Babiuk S, Yang M, Zimmerman J, Giménez-Lirola LG, Nfon C. Use of Oral Fluids for Detection of Virus and Antibodies in Pigs Infected with Swine Vesicular Disease Virus. Transbound Emerg Dis 2016; 64:1762-1770. [PMID: 27632937 DOI: 10.1111/tbed.12563] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Indexed: 01/05/2023]
Abstract
The use of swine oral fluid (OF) for the detection of nucleic acids and antibodies is gaining significant popularity. Assays have been developed for this purpose for endemic and foreign animal diseases of swine. Here, we report the use of OF for the detection of virus and antibodies in pigs experimentally infected with swine vesicular disease virus (SVDV), a virus that causes a disease clinically indistinguishable from the economically devastating foot-and-mouth disease. Viral genome was detected in OF by real-time reverse transcription polymerase chain reaction (RRT-PCR) from 1 day post-infection (DPI) to 21 DPI. Virus isolation from OF was also successful at 1-5 DPI. An adapted competitive ELISA based on the monoclonal antibodies 5B7 detected antibodies to SVDV in OF starting at DPI 6. Additionally, using isotype-specific indirect ELISAs, SVDV-specific IgM and IgA were evaluated in OF. IgM response started at DPI 6, peaking at DPI 7 or 14 and declining sharply at DPI 21, while IgA response started at DPI 7, peaked at DPI 14 and remained high until the end of the experiment. These results confirm the potential use of OF for SVD surveillance using both established and partially validated assays in this study.
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Affiliation(s)
- C Senthilkumaran
- National Centre for Foreign Animal Disease (NCFAD), Winnipeg, MB, Canada
| | - H Bittner
- National Centre for Foreign Animal Disease (NCFAD), Winnipeg, MB, Canada
| | - A Ambagala
- National Centre for Foreign Animal Disease (NCFAD), Winnipeg, MB, Canada
| | - O Lung
- National Centre for Foreign Animal Disease (NCFAD), Winnipeg, MB, Canada
| | - S Babiuk
- National Centre for Foreign Animal Disease (NCFAD), Winnipeg, MB, Canada
| | - M Yang
- National Centre for Foreign Animal Disease (NCFAD), Winnipeg, MB, Canada
| | | | | | - C Nfon
- National Centre for Foreign Animal Disease (NCFAD), Winnipeg, MB, Canada.,Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada
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19
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Mao S, Ou X, Zhu D, Chen S, Ma G, Wang M, Jia R, Liu M, Sun K, Yang Q, Wu Y, Chen X, Cheng A. Development and evaluation of indirect ELISAs for the detection of IgG, IgM and IgA1 against duck hepatitis A virus 1. J Virol Methods 2016; 237:79-85. [PMID: 27577105 DOI: 10.1016/j.jviromet.2016.08.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 08/22/2016] [Accepted: 08/26/2016] [Indexed: 11/16/2022]
Abstract
Duck hepatitis A virus 1 (DHAV-1) is the principal pathogen that causes duck viral hepatitis (DHV), a highly fatal infectious disease in ducklings. Given the importance of the humoral immune response in the clearance of DHAV-1, indirect enzyme-linked immunosorbent assays (I-ELISAs) to detect immune indices, including IgG, IgM and IgA1, were developed and evaluated in this study. The optimal concentrations of coating-antigen were 1.79μg/ml, 2.23μg/ml and 2.23μg/ml for IgG, IgM and IgA1, respectively. Meanwhile, the optimal dilutions of sera were 1:80, 1:40 and 1:40, respectively; and of the conjugates were 1:300, 1:1800 and 1:800, respectively. Based on these conditions, three linear regression equations, y=1.363+1.954x (r2=0.983), y=1.141+2.228x (r2=0.970) and y=1.103+1.559x (r2=0.995) were derived for IgG, IgM and IgA1, respectively. Analytical sensitivities of the new methods were 1:2560, 1:1280 and 1:640 for IgG, IgM and IgA1, respectively. The concordances between the I-ELISAs and serum-neutralization were 95.2% for IgG and IgA1, and 75% for IgM. Although there was a weak cross-reaction with DHAV-3 positive serum for the IgG and IgA1 tests, it didn't affect the ability to detect DHAV-1 specific antibodies. Thus, these new I-ELISAs were shown to be potentially convenient methods to survey the status of humoral immune response to DHAV-1.
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Affiliation(s)
- Sai Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - XuMin Ou
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - DeKang Zhu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - GuangPeng Ma
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - MingShu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China.
| | - RenYong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - MaFeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - KunFeng Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - XiaoYue Chen
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China
| | - AnChun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, 611130, Sichuan, People's Republic of China; China Rural Technology Development Center, Beijing, 100045, People's Republic of China.
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20
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Bjustrom-Kraft J, Woodard K, Giménez-Lirola L, Rotolo M, Wang C, Sun Y, Lasley P, Zhang J, Baum D, Gauger P, Main R, Zimmerman J. Porcine epidemic diarrhea virus (PEDV) detection and antibody response in commercial growing pigs. BMC Vet Res 2016; 12:99. [PMID: 27287624 PMCID: PMC4902975 DOI: 10.1186/s12917-016-0725-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/03/2016] [Indexed: 11/10/2022] Open
Abstract
Background Longitudinal samples from two production sites were used to (1) describe the pattern of PEDV shedding (rRT-PCR) in individual rectal swabs, pen fecal samples, and pen oral fluids (OF); (2) describe the kinetics of PEDV antibody by ELISA (IgA, IgG) testing of pig serum and pen oral fluid samples; and (3) establish cutoffs and performance estimates for PEDV WV ELISAs (IgA, IgG). Site One was PEDV positive; Site Two was PEDV negative. On Site One, pen samples (feces and oral fluids) and pig samples (rectal swabs and sera) were collected both before and after the population was exposed to PEDV. Results On Site Two, pen oral fluid samples and individual pig serum samples were negative for both PEDV antibody and nucleic acid. On Site One, PEDV was detected by rRT-PCR at 6 days post exposure (DPE) in all sample types. The last rRT-PCR positives were detected in rectal swabs and oral fluids on 69 DPE. IgG and IgA were detected in oral fluids and serum samples by 13 DPE. Analysis of the PEDV serum IgG WV ELISA data showed that a sample-to-positive (S/P) cutoff of ≥ 0.80 provided a diagnostic sensitivity of 0.87 (95 % CI: 0.82, 0.91) and specificity of 0.99 (95 % CI: 0.98, 1.00). Serum IgG results declined slowly over the monitoring period, with 60 % of serum samples positive (S/P ≥ 0.80) at the final sampling on 111 DPE. Analysis of the PEDV oral fluid IgA WV ELISA found that a cutoff of S/P ≥ 0.80 provided a diagnostic sensitivity of 1.00 (95 % CI: 0.92, 1.00) and a diagnostic specificity of 1.00 (95 % CI: 0.99, 1.00). The oral fluid IgA response increased through 96 DPE and began to decline at the last sampling on 111 DPE. Conclusions This study showed that oral fluid-based testing could provide an easy and “animal-friendly” approach to sample collection for nucleic acid and/or antibody-based surveillance of PEDV in swine populations.
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Affiliation(s)
- Jordan Bjustrom-Kraft
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - Katie Woodard
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - Luis Giménez-Lirola
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - Marisa Rotolo
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - Chong Wang
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA.,Department of Statistics, College of Liberal Arts and Sciences, Iowa State University, Osborn Drive, Ames, IA, 50011, USA
| | - Yaxuan Sun
- Department of Statistics, College of Liberal Arts and Sciences, Iowa State University, Osborn Drive, Ames, IA, 50011, USA
| | - Peter Lasley
- Smithfield Hog Production Missouri, 17999 US Highway 65, Princeton, MO, 64673, USA
| | - Jianqiang Zhang
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - David Baum
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - Phillip Gauger
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - Rodger Main
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA
| | - Jeffrey Zimmerman
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1850 Christensen Drive, Ames, IA, 50011-1134, USA.
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21
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Oral Fluids as a Live-Animal Sample Source for Evaluating Cross-Reactivity and Cross-Protection following Intranasal Influenza A Virus Vaccination in Pigs. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2015; 22:1109-20. [PMID: 26291090 DOI: 10.1128/cvi.00358-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 08/13/2015] [Indexed: 12/13/2022]
Abstract
In North American swine, there are numerous antigenically distinct H1 influenza A virus (IAV) variants currently circulating, making vaccine development difficult due to the inability to formulate a vaccine that provides broad cross-protection. Experimentally, live-attenuated influenza virus (LAIV) vaccines demonstrate increased cross-protection compared to inactivated vaccines. However, there is no standardized assay to predict cross-protection following LAIV vaccination. Hemagglutination-inhibiting (HI) antibody in serum is the gold standard correlate of protection following IAV vaccination. LAIV vaccination does not induce a robust serum HI antibody titer; however, a local mucosal antibody response is elicited. Thus, a live-animal sample source that could be used to evaluate LAIV immunogenicity and cross-protection is needed. Here, we evaluated the use of oral fluids (OF) and nasal wash (NW) collected after IAV inoculation as a live-animal sample source in an enzyme-linked immunosorbent assay (ELISA) to predict cross-protection in comparison to traditional serology. Both live-virus exposure and LAIV vaccination provided heterologous protection, though protection was greatest against more closely phylogenetically related viruses. IAV-specific IgA was detected in NW and OF samples and was cross-reactive to representative IAV from each H1 cluster. Endpoint titers of cross-reactive IgA in OF from pigs exposed to live virus was associated with heterologous protection. While LAIV vaccination provided significant protection, LAIV immunogenicity was reduced compared to live-virus exposure. These data suggest that OF from pigs inoculated with wild-type IAV, with surface genes that match the LAIV seed strain, could be used in an ELISA to assess cross-protection and the antigenic relatedness of circulating and emerging IAV in swine.
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22
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Sun H, Cunningham FL, Harris J, Xu Y, Long LP, Hanson-Dorr K, Baroch JA, Fioranelli P, Lutman MW, Li T, Pedersen K, Schmit BS, Cooley J, Lin X, Jarman RG, DeLiberto TJ, Wan XF. Dynamics of virus shedding and antibody responses in influenza A virus-infected feral swine. J Gen Virol 2015; 96:2569-2578. [PMID: 26297148 DOI: 10.1099/jgv.0.000225] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Given their free-ranging habits, feral swine could serve as reservoirs or spatially dynamic 'mixing vessels' for influenza A virus (IAV). To better understand virus shedding patterns and antibody response dynamics in the context of IAV surveillance amongst feral swine, we used IAV of feral swine origin to perform infection experiments. The virus was highly infectious and transmissible in feral swine, and virus shedding patterns and antibody response dynamics were similar to those in domestic swine. In the virus-inoculated and sentinel groups, virus shedding lasted ≤ 6 and ≤ 9 days, respectively. Antibody titres in inoculated swine peaked at 1 : 840 on day 11 post-inoculation (p.i.), remained there until 21 days p.i. and dropped to < 1 : 220 at 42 days p.i. Genomic sequencing identified changes in wildtype (WT) viruses and isolates from sentinel swine, most notably an amino acid divergence in nucleoprotein position 473. Using data from cell culture as a benchmark, sensitivity and specificity of a matrix gene-based quantitative reverse transcription-PCR method using nasal swab samples for detection of IAV in feral swine were 78.9 and 78.1 %, respectively. Using data from haemagglutination inhibition assays as a benchmark, sensitivity and specificity of an ELISA for detection of IAV-specific antibody were 95.4 and 95.0 %, respectively. Serological surveillance from 2009 to 2014 showed that ∼7.58 % of feral swine in the USA were positive for IAV. Our findings confirm the susceptibility of IAV infection and the high transmission ability of IAV amongst feral swine, and also suggest the need for continued surveillance of IAVs in feral swine populations.
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Affiliation(s)
- Hailiang Sun
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MI, USA
| | - Fred L Cunningham
- Mississippi Field Station, National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, US Department of Agriculture, Mississippi State, MI, USA
| | - Jillian Harris
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MI, USA
| | - Yifei Xu
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MI, USA
| | - Li-Ping Long
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MI, USA
| | - Katie Hanson-Dorr
- Mississippi Field Station, National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, US Department of Agriculture, Mississippi State, MI, USA
| | - John A Baroch
- National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, US Department of Agriculture, Fort Collins, CO, USA
| | - Paul Fioranelli
- Mississippi Field Station, National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, US Department of Agriculture, Mississippi State, MI, USA
| | - Mark W Lutman
- US Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Fort Collins, CO, USA
| | - Tao Li
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Kerri Pedersen
- US Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Fort Collins, CO, USA
| | - Brandon S Schmit
- National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, US Department of Agriculture, Fort Collins, CO, USA
| | - Jim Cooley
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Mississippi State, MI, USA
| | - Xiaoxu Lin
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Richard G Jarman
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Thomas J DeLiberto
- National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, US Department of Agriculture, Fort Collins, CO, USA
| | - Xiu-Feng Wan
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MI, USA
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23
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Panyasing Y, Goodell C, Kittawornrat A, Wang C, Levis I, Desfresne L, Rauh R, Gauger PC, Zhang J, Lin X, Azeem S, Ghorbani-Nezami S, Yoon KJ, Zimmerman J. Influenza A Virus Surveillance Based on Pre-Weaning Piglet Oral Fluid Samples. Transbound Emerg Dis 2014; 63:e328-38. [DOI: 10.1111/tbed.12307] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Indexed: 11/27/2022]
Affiliation(s)
- Y. Panyasing
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - C. Goodell
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - A. Kittawornrat
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - C. Wang
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
- Department of Statistics; College of Liberal Arts and Sciences; Iowa State University; Ames IA USA
| | - I. Levis
- Seaboard Farms, Inc.; Guymon OK USA
| | | | - R. Rauh
- Tetracore , Inc.; Rockville MD USA
| | - P. C. Gauger
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - J. Zhang
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - X. Lin
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - S. Azeem
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - S. Ghorbani-Nezami
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - K.-J. Yoon
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - J. Zimmerman
- Department of Veterinary Diagnostic and Production Animal Medicine; College of Veterinary Medicine; Iowa State University; Ames IA USA
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