Source: VIRGINIA POLYTECHNIC INSTITUTE submitted to NRP
EPIDEMIOLOGIC AND TOXICOLOGIC DISEASE INVESTIGATIONS IN VIRGINIA
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1000011
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
May 31, 2013
Project End Date
Mar 31, 2018
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
VIRGINIA POLYTECHNIC INSTITUTE
(N/A)
BLACKSBURG,VA 24061
Performing Department
College of Vet Medicine
Non Technical Summary
The Commonwealth of Virginia experiences costly disease outbreaks among agricultural animals every year. Recent losses associated with Salmonella outbreaks, avian influenza, cryptosporidiosis, porcine Circovirus, porcine reproductive and respiratory syndrome virus, and equine herpes virus have incurred serious financial loses for food and animal producers. The low pathogenic avian influenza (LPAI) outbreak in 2002 cost farmers $130 million on nearly 200 farms, and resulted in the deaths of 4.7 million birds. The rabies epidemic in raccoons that requires vaccination of pets and livestock has led to numerous post-exposure prophylactic treatments of people and has inflicted severe financial and emotional losses on food animal producers and companion animal owners. Thus, one important objective for these funds is to conduct investigations of disease and impaired productivity of food and companion animal populations in the Commonwealth of Virginia. A means of evaluating enzootic and epizootic diseases can be utilized in the State by relying on modern research technology and expertise. In order to provide an effective means of controlling disease in Virginia, it is essential to provide a mechanism for investigation of emerging known and unknown animal disease that also may directly or indirectly affect human health, food safety, and food security. Early detection and investigation of these outbreaks is essential to prevent significant financial losses in Virginia's agricultural animal population through the conduct of controlled, in-depth research projects designed to identify causative agents, determine pathogenesis and provide tools and procedures for interventions to control and eliminate those diseases. Animal health and productivity problems affecting populations of food animals and companion animals require thorough investigational response. The depth of investigation required often exceeds what is feasible in routine diagnostic procedures. However, facilities for such in-depth studies should be available, particularly in the study of diseases having multiple interactions and for parasitic and infectious diseases of high economic importance to the state. There is no adequate substitute for the more extensive alternative of carefully planned on-site studies.
Animal Health Component
40%
Research Effort Categories
Basic
60%
Applied
40%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3113899109010%
3113899110010%
3113899110130%
3113899111030%
3113899115010%
3113899117010%
Knowledge Area
311 - Animal Diseases;

Subject Of Investigation
3899 - Other animals, general;

Field Of Science
1090 - Immunology; 1101 - Virology; 1100 - Bacteriology; 1110 - Parasitology; 1150 - Toxicology; 1170 - Epidemiology;
Goals / Objectives
To conduct a rapid response investigation of any emerging disease that impairs productivity of food animal populations or threatens public health in the Commonwealth of Virginia. To investigate disease entities which have been identified as being of unknown etiology and/or having potential risk of causing undue economic loss to agricultural animals or a public health risk in the Commonwealth of Virginia. To support the generation of baseline productivity data from flocks and herds where record systems are inadequate in order to assess the need and effect of research on productivity levels. To support economic analysis of the impact of specific diseases on farm animal productivity to initiate control programs and defines research priorities. To generate preliminary epidemiologic data on complex disease interaction, parasitic disease, infectious disease, and toxicological disease problems to support application for specific research funding. To supplement field investigations in which toxicological agents are suspected. To develop analytical techniques for toxic substances of known clinical importance in Virginia. To develop strategies and to identify the scientific expertise available to conduct research studies in the fields of new, emerging, re-emerging disease and agro and bioterrorism.
Project Methods
The Senior Associate Dean for Research and Graduate Studies allocates funds to faculty after receipt of brief descriptions of the problem to be studied, potential impact on agriculture within the state, proposed investigational plan, and budget. The Senior Associate Dean must be satisfied that this problem represents a new and significant condition in the state and/or the potential to reach epizootic proportions or have a public health impact. Long-range studies to monitor existing conditions or to identify evolving disease conditions will be reviewed by the team of consultants. Proposals will be presented in the same format as required for Hatch projects and will be reviewed using similar criteria.

Progress 05/31/13 to 03/31/18

Outputs
Target Audience:Veterinarians, researchers, and fellow scientist through the publication of journal articles and presentations of research findings at conferences. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Students and post-docs on the project developed competencies in laboratory skills and information literacy. How have the results been disseminated to communities of interest?Through peer-review publications. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Research continued in the major goals areas above. Work on these goals over the last five years lead to the establishment of expertise at the College of Veterinary Medicine. Most of this reporting period was spent in bulding collaboration among individuals involved in the goals above to produce goals for the next 5 years of this ongoing project.

Publications


    Progress 10/01/16 to 09/30/17

    Outputs
    Target Audience:Veterinarians and scientists through the publications of journal articles and presentation of research findings at conferences. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Students and post-docs on the project developed competencies in laboratory skills and information literacy How have the results been disseminated to communities of interest?Through peer-review publications. What do you plan to do during the next reporting period to accomplish the goals?Continue to investigate outbreaks that occur in the Commonwealth of Virginia.

    Impacts
    What was accomplished under these goals? 1. The currentin vitrotitration method for turkey hemorrhagic enteritis virus (THEV) is the end-point dilution assay (EPD) in suspension cell culture (CC). This assay is subjective and results in high variability among vaccine lots. In this study, a newin vitroinfectivity method combining a SYBR Green I-based qPCR assay and CC was developed for titration of live hemorrhagic enteritis (HE) CC vaccines. The qPCR was used to determine the virus genome copy number (vGCN) of the internalized virus particles following inoculation of susceptible RP19 cells with 1 vaccine label dose. The measured vGCN represents the number of infectious viral particles (IVP) per 1 dose. This method was used to compare 9 vaccine lots from 3 companies in the United States. Significant lot-to-lot variations within the same company and among the various companies were found in genomic and qPCR-based infectious titer per label dose. A positive linear relationship was found between qPCR infectious titer and genomic titer. Further, considerable variations in CCID50titers were found among tested vaccine lots, indicating the high variability of the current titration methods. The new method provides an alternative to classical titration assays and can help reduce variation among HE vaccine products. 2. Studies indicate that persistent Salmonella colonization occurs in poultry that are infected early in life, leading to both food safety and public health concerns. Development of improved preharvest Salmonella management strategies is needed to reduce poultry product contamination. The objective of this study was to evaluate the efficacy of a product containing medium chain fatty acids (MCFA) for reducing early Salmonella colonization in turkey poults. Day-of-hatch turkeys were provided a standard starter diet supplemented with MCFA at 0 (negative and positive controls), 1.5, 3, 4.5, or 6 lbs/ton of feed. Positive control and MCFA treated birds were also crop-gavaged with 108colony forming units (CFU) of bioluminescent Salmonella Typhimurium. Gastrointestinal tissue samples were collected at 3 days postinoculation for bioluminescence imaging (Meckel's diverticulum to the cloaca) and selective enumeration (cecal contents). Quantification of bioluminescence indicated that the 4.5 and 6 lbs/ton MCFA groups had significantly less colonization than the positive control group (p = 0.0412 and p < 0.0001, respectively). Similarly, significantly lower numbers (1-log10CFU/g reduction) of Salmonella were observed in the ceca of the 6 lbs/ton MCFA group compared to the positive control group (p = 0.0153). These findings indicate that incorporation of MCFA in turkey diets can significantly reduce early Salmonella colonization. In addition, this study highlights the utility of bioluminescence imaging as a screening methodology for assessing the efficacy of treatments that may reduce Salmonella in poultry. 3. Emerging and re-emerging diseases are continuously diagnosed in poultry species. A few of these diseases are known to cross the species barrier, thus posing a public health risk and an economic burden. We identified and synthesized global evidence for poultry nonfoodborne zoonoses to better understand these diseases in people who were exposed to different poultry-related characteristics (e.g., occupational or nonoccupational, operational types, poultry species, outbreak conditions, health status of flocks). This review builds on current knowledge on poultry zoonoses/potentially zoonotic agents transmitted via the nonfoodborne route. It also identifies research gaps and potential intervention points within the poultry industry to reduce zoonotic transmission by using various knowledge synthesis tools such as systematic review (SR) and qualitative (descriptive) and quantitative synthesis methods (i.e., meta-analysis). Overall, 1663 abstracts were screened and 156 relevant articles were selected for further review. Full articles (in English) were retrieved and critically appraised using routine SR methods. In total, eight known zoonotic diseases were reviewed: avian influenza (AI) virus (n = 85 articles), Newcastle disease virus (n = 8), West Nile virus (WNV, n = 2), avian Chlamydia (n = 24), Erysipelothrix rhusiopathiae (n = 3), methicillin-resistant Staphylococcus aureus (MRSA, n = 15), Ornithonyssus sylvarium (n = 4), and Microsporum gallinae (n = 3). In addition, articles on other viral poultry pathogens (n = 5) and poultry respiratory allergens derived from mites and fungi (n = 7) were reviewed. The level of investigations (e.g., exposure history, risk factor, clinical disease in epidemiologically linked poultry, molecular studies) to establish zoonotic linkages varied across disease agents and across studies. Based on the multiple outcome measures captured in this review, AI virus seems to be the poultry zoonotic pathogen that may have considerable and significant public health consequences; however, epidemiologic reports have only documented severe human cases clustered in Asia and not in North America. In contrast, avian Chlamydia and MRSA reports clustered mainly in Europe and less so in North America and other regions. Knowledge gaps in other zoonoses or other agents were identified, including potential direct (i.e., nonmosquito-borne) transmission of WNV from flocks to poultry workers, the public health and clinical significance of poultry-derived (livestock-associated) MRSA, the zoonotic significance of other viruses, and the role of poultry allergens in the pathophysiology of respiratory diseases of poultry workers. Across all pathogens reviewed, the use of personal protective equipment was commonly cited as the most important preventive measure to reduce the zoonotic spread of these diseases and the use of biosecurity measures to reduce horizontal transmission in flock populations. The studies also emphasized the need for flock monitoring and an integrated approach to prevention (i.e., veterinary-public health coordination with regard to diagnosis, and knowledge translation and education in the general population) to reduce zoonotic transmission. 4. Oncolytic virotherapy is a promising novel approach that overcomes the limitations posed by radiation and chemotherapy. In this study, the oncolytic efficacy of a recombinant Newcastle disease virus (rNDV) BC-KLQL-GFP, against prostate cancer stem-like/tumor initiating cells was evaluated. Xenograft derived prostaspheres (XPS) induced tumor more efficiently than monolayer cell derived prostaspheres (MCPS) in nude mice. Primary and secondary XPS show enhanced self-renewal and clonogenic potential compared to MCPS. XPS also expressed embryonic stem cell markers, such as Nanog, CD44 and Nestin. Further, prostate specific antigen (PSA) activated recombinant Newcastle Disease Virus (rNDV) was selectively cytotoxic to tumor derived DU145 prostaspheres. An effective concentration (EC50) of 0.11-0.14 multiplicity of infection was sufficient to cause prostasphere cell death in serum free culture. DU145 tumor xenograft derived prostaspheres were used as tumor surrogates as they were enriched for a putative tumor initiating cell population. PSA activated rNDV was efficient in inducing cell death of cells and prostaspheres derived from primary xenografts ex-vivo, thus signifying a potential in vivo efficacy. The EC50(∼0.1 MOI) for cytolysis of tumor initiating cells was slightly higher than that was required for the parental cell line, but within the therapeutic margin for safety and efficacy.

    Publications

    • Type: Journal Articles Status: Accepted Year Published: 2017 Citation: Mahsoub HM, Evans NP, Beach NM, Yuan L, Zimmerman K, Pierson FW. Real-time PCR-based infectivity assay for the titration of turkey hemorrhagic enteritis virus, an adenovirus, in live vaccines. J Virol Methods. 2017 Jan;239:42-49. doi: 10.1016/j.jviromet.2016.11.002. Epub 2016 Nov 6.
    • Type: Journal Articles Status: Accepted Year Published: 2017 Citation: Evans NP, Collins DA, Pierson FW, Mahsoub HM, Sriranganathan N, Persia ME, Karnezos TP, Sims MD, Dalloul RA. Investigation of Medium Chain Fatty Acid Feed Supplementation for Reducing Salmonella Typhimurium Colonization in Turkey Poults. Foodborne Pathog Dis. 2017 Sep;14(9):531-536. doi: 10.1089/fpd.2016.2273. Epub 2017 Jul 11.
    • Type: Journal Articles Status: Accepted Year Published: 2017 Citation: Raghunath S, Pudupakam RS, Allen A, Biswas M, Sriranganathan N. Genetically engineered oncolytic Newcastle disease virus mediates cytolysis of prostate cancer stem like cells. J Biotechnol. 2017 Oct 20;260:91-97. doi: 10.1016/j.jbiotec.2017.09.015. Epub 2017 Sep 19.


    Progress 10/01/15 to 09/30/16

    Outputs
    Target Audience:Disseminate research findings through publications of journal articles and conference presentations to veterinarians and scientists Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Students and post-docs on the projects developed competencies in laboratory skills and information literacy. How have the results been disseminated to communities of interest?Peer-reviewed publications. What do you plan to do during the next reporting period to accomplish the goals?Continue to investigate outbreaks that occur in the Commonwealth of Virginia.

    Impacts
    What was accomplished under these goals? A gnotobiotic pig model was used to study the infectivity of norovirus; research was performed to develop a more effective brucellosis vaccine in elk; numerous studies were done to understand Hepatitis E virus and develop vaccine candidates. The Toxicology Laboratory has assisted several veterinarians and faculty members involving toxicity related problems. Veterinarians from the Department Homeland of Security requested the analysis of about 100 dog blood and plasma samples for possible exposure to organophosphates or carbamates. Our role was to quantify the acetyl cholinesterase levels in blood and the pseudocholinesterase levels in serum from these dogs. A colorimetric test and a microplate reader were used for thispurpose. Toxicology has also been involved in helping Dr. David Kuhn in the Department of Food Science & Technology to assess the metals and minerals content of farm-raised fish. Fish muscles have been prepared by microwave-assisted acid digestion and the metals/minerals quantified by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). We also have been involved in doing selenium speciation from fish muscle tissues for the same faculty: measuring inorganic and organic selenium species (for example: selenomethionine).The samples were digested with proteases to release the metals bound to proteins; organic and inorganic selenium species were then separated by High Pressure Liquid Chromatography and analyzed in-line by ICP-MS. Toxicology has always been working closely with veterinarians at the Virginia Teaching Hospital (VTH) or from private practices, to measure levels of metals/minerals and vitamins (vitamin A or E) and to determine the possibility ofany nutritional imbalances in livestock and companion animals.

    Publications

    • Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Lei S, Ryu J, Wen K, Twitchell E, Bui T, Ramesh A, Weiss M, Li G, Samuel H, Clark-Deener S, Jiang X, Lee K*, Yuan L*. 2016. Increased and prolonged human norovirus infection in RAG2/IL2RG deficient gnotobiotic pigs with severe combined immunodeficiency. Sci. Rep. 6, 25222; doi:10.1038/srep25222. PMC4846862.
    • Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Lei S, Samuel H, Twitchell E, Bui T, Ramesh A, Wen K, Weiss M, Li G, Yang X, Jiang X, Yuan L*. 2016. Enterobacter cloacae inhibits human norovirus infectivity in gnotobiotic pigs. Sci. Rep. 6, 25017; doi:10.1038/srep25017. PMC4845002.
    • Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Nol, P., Olsen, S. C., Rhyan, J. C., Sriranganathan, N., McCollum, M. P., Hennager, S. G., Salman, M. D. (2016). Vaccination of Elk (Cervus canadensis) with Brucella abortus Strain RB51 Overexpressing Superoxide Dismutase and Glycosyltransferase Genes Does Not Induce Adequate Protection against Experimental Brucella abortus Challenge. Frontiers in Cellular and Infection Microbiology, 6, 10. http://doi.org/10.3389/fcimb.2016.00010.
    • Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Xia M, Wei C, Wang L, Cao D, Meng XJ, Jiang X, Tan M. 2016. Development and evaluation of two subunit vaccine candidates containing antigens of hepatitis E virus, rotavirus, and astrovirus. Sci Rep. May 19;6:25735. doi: 10.1038/srep25735.
    • Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Xia M, Wei C, Wang L, Cao D, Meng XJ, Jiang X, Tan M. A trivalent vaccine candidate against hepatitis E virus, norovirus, and astrovirus. Vaccine. 2016 Feb 10;34(7):905-13. doi: 10.1016/j.vaccine.2015.12.068.
    • Type: Journal Articles Status: Accepted Year Published: 2015 Citation: Kenney SP, Wentworth JL, Heffron CL, Meng XJ. Replacement of the hepatitis E virus ORF3 protein PxxP motif with heterologous late domain motifs affects virus release via interaction with TSG101. Virology. 2015 Dec., 486:198-208. doi: 10.1016/j.virol.2015.09.012.


    Progress 10/01/14 to 09/30/15

    Outputs
    Target Audience:Veterinarians and scientists through the publications of journal articles and presentation of research findings at conferences. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Students and Post-Docs on the project developed competencies in laboratory skills and information literacy. How have the results been disseminated to communities of interest?Through peer-reviewed publications. What do you plan to do during the next reporting period to accomplish the goals?Continue to investigate outbreaks that occur in the Commonwealth of Virginia.

    Impacts
    What was accomplished under these goals? Discovery of a novel pathogenic Mammalian orthoreovirus from diarrheic pigs and Swine blood meal in the United States. We isolated and characterized a novel mammalian orthoreovirus 3 (MRV3) from diarrheic feces of piglets from these outbreaks in three states and ring-dried swine blood meal from multiple sources. MRV3 could not be isolated from healthy or pigs that had recovered from epidemic diarrhea from four states. Several MRV3 isolates were obtained from chloroform-extracted pig feces or blood meal in cell cultures or developing chicken embryos. Biological characterization of two representative isolates revealed trypsin resistance and thermostability at 90°C. NextGen sequencing of ultrapurified viruses indicated a strong homology of the S1 segment to mammalian and bat MRV3. Neonatal piglets experimentally infected with these viruses or a chloroform extract of swine blood meal developed severe diarrhea and acute gastroenteritis with 100% mortality within 3 days postinfection. Therefore, the novel porcine MRV3 may contribute to enteric disease along with other swine enteric viruses. Development of a novel vaccine that confers heterologous protection against porcine reproductive and respiratory syndrome virus (PRRSV). Wepreviously demonstrated that chimeric PRRSVs in which a single envelope gene (ORF3, ORF4, ORF5 or ORF6) was shuffled via DNA shuffling had an improved heterologous cross-neutralizing ability. Subsequently, we incorporate all of the individually-shuffled envelope genes together in different combinations into an infectious clone backbone of PRRSV MLV. Five viable progeny chimeric viruses were rescued, and their growth characteristics were characterized in vitro. Two chimeric viruses were found to induce cross-neutralizing antibodiesagainst heterologous strains. A subsequent vaccination/challenge study in 72 pigs revealed that chimeric virus FV-SPDS-VR2 and parental virus conferred partial cross-protection when challenged with heterologous strains NADC20 or MN184B.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Pavio N, X.J. Meng, and V. Doceul. 2015. Zoonotic origin of hepatitis E. Current Opinion in Virology. 10:34-41.
    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Park SJ, Lee B-W, Moon H-W, Sung HW, Yoon B-I, Meng XJ, and Kwon HM. 2015. Construction of an infectious cDNA clone of genotype 1 avian hepatitis E virus: Characterization of its pathogenicity in broiler breeders and demonstration of its utility in studying the role of the hypervariable region in virus replication. Journal of General Virology. 96(Pt 5):1015-26.
    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Thimmasandra Narayanappa A, Sooryanarain H, Deventhiran J, Cao D, Ammayappan Venkatachalam B, Kambiranda D, LeRoith T, Heffron CL, Lindstrom N, Hall K, Jobst P, Sexton C, Meng XJ, Elankumaran S. 2015. A novel pathogenic mammalian orthoreovirus from diarrheic pigs and swine blood meal in the United States. mBio 6(3):e00593-15.
    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Richmond O, T.E. Cecere, E. Edrogan, X.J. Meng, P. Pi�eyro, S. Subramaniam, S. Todd, and T. LeRoith. 2015. PD-L1 expression is increased in monocyte derived dendritic cells in response to porcine circovirus type 2 and porcine reproductive and respiratory syndrome virus infections. Veterinary Immunology and Immunopathology. 168:24-29.
    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Gerber PF, D.W. Trampel, E.M. Willinghan, P. Billam, X.J. Meng,and T. Opriessnig. 2015. Subclinical avian hepatitis E virus infection in layer flocks in the United States. The Veterinary Journal. 206(3): 304-311.


    Progress 10/01/13 to 09/30/14

    Outputs
    Target Audience: Veterinarians and scientists through the publications of journal articles and presentation of research findings at conferences. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Progress and accomplishments for the next reporting period will depend on any outbreaks that may occur in the Commonwealth of Virginia.

    Impacts
    What was accomplished under these goals? (1). Targeting PRRSV vaccine directly to dendritic cells: The Virginia Tech team demonstrated that PRRSV antigen was targeted efficiently to dendritic cells through antibodies specific to a porcine c-type lectin receptor (CLR) molecule DC-SIGN (dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin) in pigs. A recombinant PRRSV antigen (shGP45M) was constructed by fusing secretory-competent subunits of GP4, GP5 and M proteins derived from genetically-shuffled strains of PRRSV. In vaccinated pigs, when the PRRSV shGP45M antigen was delivered through a recombinant mouse-porcine chimeric antibody specific to the porcine DC-SIGN(pDC-SIGN) neck domain, porcine DCs rapidly internalized them in vitro and induced higher numbers of antigen-specific interferon-? producing CD4 T cells compared to the pigs receiving non-targeted PRRSV shGP45M antigen. The pDC-SIGN targeting of recombinant PRRSV antigen may improve protective immunity against PRRSV by inducing efficient T cell responses. (2). Synthetic attenuation of PRRSV for vaccine development: The Virginia Tech team utilizes synthetic attenuatedvirusengineering (SAVE) approach to rapidly attenuate PRRSV. The major envelope GP5 gene ofPRRSVwascodon-pair deoptimized aided by a computer algorithm. The codon-pair deoptimizedvirus, designated as SAVE5 with a deoptimized GP5 gene, was successfully rescued in vitro. The SAVE5virusreplicated at a lower level in vitro with a significant decrease of GP5 protein expression compared to the wtPRRSVVR2385virus. Pigs experimentally infected with the SAVE5virushad significantly lower viremia level up to 14 days post-infection as well as significantly reduced gross and histological lunglesions when compared to wild-typePRRSVVR2385virus-infected pigs, indicating the attenuation of the SAVE5virus. Pigs vaccinated with the attenuated SAVE5 virus were challenged with a homologous strain and the SAVE5 virus was shown to be successful in reducing macroscopic lung lesions after homologous challenge compared to unvaccinated pigs. (3).Tracking the origin and evolution of PEDV viruses in the United States: After the emergence of PEDV in the United States, the Virginia Tech team determined its origin, evolution, and genotypes based on temporal and geographical evidence. Genetic and phylogenetic analyses of the three U.S. strains revealed a close relationship with ChinesePEDVstrains and their likely Chinese origin. The U.S.PEDVstrains underwent evolutionary divergence, which can be classified into two sublineages. The emergent U.S. strains are most closely related to a strain isolated in 2012 from Anhui Province in China, which might be the result of multiple recombination events between different genetic lineages or sublineages ofPEDV. Molecular clock analysis of the divergent time based on the complete genomic sequences is consistent with the actual time difference, approximately 2 to 3 years, of the PED outbreaks between China (December 2010) and the United States (May 2013). The emergent U.S.PEDVstrains share unique genetic features at the 5'-untranslated region with a bat coronavirus, thus supporting an evolutionary origin ofPEDVfrom bats.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2014 Citation: Opriessnig T,Xiao CT, Gerber PF, Halbur PG, Matzinger SR, and X.J. Meng. Mutant USA strain of porcine circovirus type 2 (mPCV2) exhibits similar virulence to the classical PCV2a and PCV2b strains in caesarian-derived colostrum-deprived pigs. Journal of General Virology. 95(Pt 11):2495-503.
    • Type: Book Chapters Status: Published Year Published: 2014 Citation: Meng X.J. Hepatitis E. In: Kaslow RA, Stanberry LA and LeDuc JW (eds). Viral Infections of Humans: Epidemiology and Control, 5th Edition. Springer Publishing, NY. pp 439-454.
    • Type: Journal Articles Status: Published Year Published: 2014 Citation: Ni YY, Z. Zhao, T. Opriessnig, S. Subramaniam, L. Zhou, D. Cao, Q. Cao, H. Yang, and X.J. Meng. Computer-aided codon-pairs deoptimization of the major envelope GP5 gene attenuates porcine reproductive and respiratory syndrome virus. Virology. 450-451:132-139
    • Type: Journal Articles Status: Published Year Published: 2014 Citation: Wang L, Xia M, Huang P, Fang H, Cao D, Meng X.J., McNeal M, Jiang X, and Tan M. Branched-linear and agglomerate protein polymers as vaccine and vaccine platform. Biomaterials. 35: 8427-8438.
    • Type: Journal Articles Status: Published Year Published: 2014 Citation: Gerber PF, L.G. Gim�nez-Lirola, P.G. Halbur, L. Zhou, X.J. Meng, Y. Fang, and T. Opriessnig. Comparison of commercial enzyme-linked immunosorbent assays and fluorescent microbead immunoassays for detection of antibodies against porcine reproductive and respiratory syndrome virus in boars. Journal of Virological Methods. 197:63-66.
    • Type: Journal Articles Status: Published Year Published: 2014 Citation: Gim�nez-Lirola LG, P.F. Gerber, R.R. Rowland, P.G. Halbur, Y.W. Huang, X.J. Meng, and T. Opriessnig. Development and validation of a 4-plex antibody assay for simultaneous detection of IgG antibodies against Torque teno sus virus 1 (TTSuV1), TTSuV2, and porcine reproductive and respiratory syndrome virus types 1 and 2. Research in Veterinary Sciences. 96(3):543-550.
    • Type: Journal Articles Status: Published Year Published: 2013 Citation: Huang YW, A.W. Dickerman, P. Pineyro, L. Li, L. Fang, R. Kiehne, T. Opriessnig, and X.J. Meng. Origin, evolution, and genotyping of emergent porcine endemic diarrhea virus (PEDV) strains in the United States. mBio. 4(5):e00737-13. doi:10.1128/mBio.00737-13.


    Progress 05/31/13 to 09/30/13

    Outputs
    Target Audience: Swine producers Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Continue to investigate any outbreaks in the Commonwealth of Virginia. Continue working on thePEDV outbreak and work towards the development of effective preventative and control measures.

    Impacts
    What was accomplished under these goals? The sudden emergence of porcine epidemic diarrhea virus (PEDV), a coronavirus, for the first time in the United States causes significant economic and public health concerns. Since its recognition in May 2013, PEDV has rapidly spread across the United States, resulting in high mortality in piglets in more than 17 States. The ongoing outbreaks of Middle East respiratory syndrome coronavirus in humans from countries in or near the Arabian Peninsula, and the historical deadly nature of the 2002 outbreaks of severe acute respiratory syndrome coronavirus, create further anxiety over the emergence of PEDV in the United States due to the lack of scientific information about the origin and evolution of this emerging coronavirus. Here we report the detailed genetic characterization, origin, and evolution of emergent PEDV strains in the United States. The results provide much needed information to devise effective preventive and control strategies against PEDV in the United States. We report here the emergence of PEDV in the United States and detailed genetic and phylogenetic analyses of the complete genomic sequences of three emergent U.S. PEDV strains from Minnesota and Iowa. The findings that the emergent U.S. PEDV strains are most closely related to Chinese G2a strains suggest that the emergence of the PEDV in the United States likely originated from China. However, the exact source of the origin is difficult to identify at this point. The finding that the emergent PEDV strains in the United States share unique genetic features with a bat coronavirus further suggests a possible evolutionary origin of PEDV from bat species and potential cross-species transmission. The information presented in this study will guide the current control measures to stop the ongoing spread of PEDV in the United States and also provides important clues for the development of an effective vaccine against the emergent PEDV strains.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2013 Citation: Yao-Wei Huang, Allan W. Dickerman, Pablo Pi�eyro, Long Li, Li Fang, Ross Kiehne, Tanja Opriessnig, Xiang-Jin Meng Origin, Evolution, and Genotyping of Emergent Porcine Epidemic Diarrhea Virus Strains in the United States. mBio, 2013, 4(5):00737-13.