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Avian Bornavirus : A Common and Emerging Pathogen in North American Waterfowl

Avian Bornavirus : A Common and Emerging Pathogen in North American Waterfowl. Avian Bornavirus. Order Mononegavirales ; Family Bornaviridae Enveloped Non-segmented , negative strand RNA genome; encodes 6 proteins Neurotropic

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Avian Bornavirus : A Common and Emerging Pathogen in North American Waterfowl

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  1. Avian Bornavirus: A Common and Emerging Pathogen in North American Waterfowl

  2. Avian Bornavirus • Order Mononegavirales; Family Bornaviridae • Enveloped • Non-segmented, negative strand RNA genome; encodes 6 proteins • Neurotropic • Replication is nuclear, non-cytopathic, highly cell-associated ABV-CG infected DEF showing intense nuclear staining (anti-N) and diffuse cytoplasmic staining

  3. L G X P M N Anatomy of a bornavirus • Enveloped • Helical nucleocapsid • Single glycoprotein

  4. Genome Arrangement S1 S3 S2 glycoprotein G 5’ X 3’ N P M L nucleocapsid RdRp T1 T2 T3 T4 • S1-3 transcript Start sites • T1-4 transcript Termination sites • At least 8 transcripts generated by use of alternative transcript start and stop sites and splicing

  5. Type Species: • Borna disease virus (BDV) • Until 2008 the onlybornavirus • Highly neurotropic BORNA

  6. Borna Disease The highest mortality is in horses and sheep BDV infects other mammals, including cats (staggering disease) and humans (psychiatric disease?) Natural transmission of BDV via small mammalian vectors (and birds?) Bi-colored white toothed shrew Bank vole

  7. ‘Avian Bornavirus Syndrome’ • Neurologic and Digestive tract components • Major killer of parrots in aviculture since the 1970s • Avian bornavirusidentified at the etiologic agent in 2008 Neuronal SignsGastrointestinal Signs • Ataxia • Blindness • Abnormal head • movements • Seizures • Undigested food • Diarrhea • Weight loss • Starvation • Enlarged proventriculus • ABV Transmission: • Fecal Oral • Airborne spread • Vertical transmission

  8. ABV4 and ABV2 are by far the most common in the captive parrot population

  9. When and how did avian bornavirus enter the captive parrot population? ? Proventricular Impaction Associated with Nonsuppurative Encephalomyelitis and Ganglioneuritis in 2 Canada Geese. Journal of Wildlife Diseases. 1991. 27:513-517

  10. Detection of ABV in Cloacal Swabs 4% 6.4% 2.7% • Samples were collected by USDA-Fish and Wildlife services, 2007 - 2009 for H5N1 AIV detection • Used RT-PCR to test > 600 samples

  11. Incidence of ABV RNA in Brain Samples 15.3% 14.5% 9% 44% 8.3% 22% 6.5% 33% 24% 10% 10% 19% Culled for airplane avoidance No. individuals

  12. Avian Bornavirusin Waterfowl

  13. Incidence of ABV in Gulls in NY and NJ (0/7) (0/4) (0/7) (4/36) (0/1) (0/35) (4/12)

  14. Canada Goose Mute Swan Mallard Gull

  15. Bornavirus phylogeny (2012) 81 – 83% nt identity ABV5 BDV 70 – 72% nt identity ABV7 ABV1 ABV3 ABV Canary ABV2 ABV EF ABV4 ABV Canada goose Units of measure are substitutions per nucleotide of the bornavirus genome

  16. Bornavirus phylogeny (2014) 81 – 83% nt identity ABV5 BDV 70 – 72% nt identity ABV7 ABV1 ABV3 ABV Canary ABV2 ABV EF ABV4 ABV Canada goose Units of measure are substitutions per nucleotide of the bornavirus genome

  17. Is ABV a major cause of morbidity and mortality in wild birds?

  18. Retrospective Study: Canada Geese and Trumpeter Swans • Samples collected between 1992 and 2011 • 51 samples met the case criteria (non-supportive encephalitis, no diagnosis) • 40 (78%) were ABV positive • 9 ‘control’ samples • 1 (11%) was ABV positive Delnatte, P. Ojkic, D. DeLay, J. Campbell, D., Crawshaw, G & D. Smith. 2013. Pathology and diagnosis of avian bornavirus infection in wild Canada geese (Brantacanadensis), trumpeter swans (Cygnus buccinator) and mute swans (Cygnus olor) in Canada: a retrospective study. Avian Pathology, 42:2, 114-128, DOI: 10.1080/03079457.2013.769669

  19. Lymphocytic infiltrates in brain of a PCR positive gull Gull, New Jersey, US

  20. ABV antigen in retina of a PCR positive mallard duck Mallard 89 (2014) retina, IHC00

  21. Ongoing study:ABV infection in a Canada goose with ataxia and weight- loss (2014)* PCR + Virus growth + Lymphocytic infiltrates (H&E) + Immunohistochemistry (ABV N) + *Submitted to the Wildlife Clinic, Tufts Cummings School of Veterinary Medicine Maureen Murray, DVM, DABVP Clinical Assistant Professor Wildlife Clinic Tufts Cummings School of Veterinary Medicine

  22. Ongoing study: White-winged dove*Neurologic signsPCR + (ABV2)Lymphocytic infiltrates (H&E) +Immunohistochemistry (ABV N) + *Submitted to Texas A&M College of Veterinary Medicine

  23. Bornavirus phylogeny (2014) 81 – 83% nt identity ABV5 BDV 70 – 72% nt identity ABV7 ABV1 ABV3 ABV Canary ABV2 ABV EF ABV4 ABV Canada goose Units of measure are substitutions per nucleotide of the bornavirus genome

  24. Acknowledgements Texas A&M • JianhuaGuo LinaCovaleda NeginYousefpour • Sameer Hamid Jean Leal de Araujo Debra Turner • J. Jill Heatley Sharman Hoppes Jeffrey Musser • Ian Tizard USDA/APHIS Wildlife Services Seth Swafford John Barock California Animal Health and Food Safety Laboratory H. L. Shivaprasad University of Guelph Dale Smith Pauline Delnatte This work was funded in part by the Richard M Schubot Endowment at Texas A&M University.

  25. Do ABV-infected geese get out of the way? January 15, 2009, US Airways Flight 1549

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