1 / 51

Avian Influenza (Highly Pathogenic)

Avian Influenza (Highly Pathogenic). Fowl plague, Fowl pest, Peste aviaire, Geflugelpest, Typhus exudatious gallinarium, Brunswick bird plague, Brunswick disease, Fowl disease, Fowl or bird grippe. Overview. Organism Economic Impact Epidemiology Transmission Clinical Signs

RoyLauris
Download Presentation

Avian Influenza (Highly Pathogenic)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Avian Influenza (Highly Pathogenic) Fowl plague, Fowl pest, Peste aviaire, Geflugelpest, Typhus exudatious gallinarium, Brunswick bird plague, Brunswick disease, Fowl disease, Fowl or bird grippe

  2. Overview • Organism • Economic Impact • Epidemiology • Transmission • Clinical Signs • Diagnosis and Treatment • Prevention and Control • Actions to take Center for Food Security and Public Health, Iowa State University, 2008

  3. The Organism

  4. Influenza Virus • Family Orthomyxoviridae • “myxo” means mucus • Three main types • Type A • Multiple species • Type B • Humans • Type C • Humans and swine Center for Food Security and Public Health, Iowa State University, 2008

  5. Influenza A • Multiple species • Humans, pigs, horses, birds, others • Most virulent group • Classification by surface antigensinto subtypes • Hemagglutinin (H or HA) • Neuraminidase (N or NA) Center for Food Security and Public Health, Iowa State University, 2008

  6. Influenza A Center for Food Security and Public Health, Iowa State University, 2008

  7. Influenza A Center for Food Security and Public Health, Iowa State University, 2008

  8. Center for Food Security and Public Health, Iowa State University, 2008

  9. Influenza B • Mostly humans • Common • Less severe than A • Epidemics occur less often than A • Human seasonal vaccine • Two strains of type A • One strain of type B Center for Food Security and Public Health, Iowa State University, 2008

  10. Influenza C • Humans and swine • Different pattern of surface proteins • Rare • Mild to no symptoms • By age 15, most have antibodies Center for Food Security and Public Health, Iowa State University, 2008

  11. Avian Influenza • Disease based on genetic features and/or severity of disease in poultry • Low pathogenic AI (LPAI) • H1 to H16 subtypes • Highly pathogenic AI (HPAI) • Some H5 or H7 subtypes • LPAI H5 or H7 subtypes can mutate into HPAI Center for Food Security and Public Health, Iowa State University, 2008

  12. Importance

  13. History • 1878: First identified case in Italy • 1924-25: First U.S. cases • Mildly pathogenic avian influenza first identified mid-twentieth century • 1970’s • Migratory waterfowl carriers • Outbreaks in mink, seals and whales Center for Food Security and Public Health, Iowa State University, 2008

  14. Economic Impact • Direct losses: • Depopulation and disposal • High morbidity and mortality • Quarantine and surveillance • Indemnities • 1978-1996: Seasonal outbreaks in Minnesota cost taxpayers $22 million Center for Food Security and Public Health, Iowa State University, 2008

  15. Economic Impact • 1983: U.S. outbreak (H5N2) • $65 million in losses • Destruction of 17 million birds • 30% increase in egg prices • 1999-2000: Italy outbreak (H7N1) • $100 million in compensation to farmers • 18 million birds destroyed • Indirect losses of $500 million Center for Food Security and Public Health, Iowa State University, 2008

  16. Economic Impact • 1997: Hong Kong outbreak (H5N1) • $13 million for depopulation and indemnities • 1.4 million birds • 2001: Hong Kong outbreak (H5N1) • 1.2 million birds • $3.8 million • 2003: European outbreak (H7N7) • 30 million birds destroyed • $314 million Center for Food Security and Public Health, Iowa State University, 2008

  17. Epidemiology

  18. Geographic Distribution • Worldwide distribution • Reservoir • Free flying aquatic birds: Ducks, geese, shorebirds, gulls, terns, auks • Outbreaks worldwide now • Similarity to Newcastle Disease makes actual distribution difficult to define • Altered avian ecosystems have created new niche for AI viruses Center for Food Security and Public Health, Iowa State University, 2008

  19. Epidemiology: Birds • Initial source of infection • Migrating ducks or other waterfowl • Spread by aerosol, shared drinking water, fomites • To other migratory waterfowl, domestic poultry and pigs, pet birds • Virus found in respiratory secretions and feces Center for Food Security and Public Health, Iowa State University, 2008

  20. Epidemiology: Pigs • Susceptible to infection with all subtypes of avian influenza A • Called a “mixing vessel” • Receptors for both avian and human influenza virus • In US H1N1 stable for almost 30 years • Now H1N1, H3N2, H1N2 Center for Food Security and Public Health, Iowa State University, 2008

  21. Transmission

  22. Animal Transmission • Initial source of infection • Other poultry, migratory waterfowl, domestic pigs, pet birds • Spread by aerosol, shared drinking water, fomites • Virus in respiratory secretions and feces • Virus present in eggs but eggs unlikely to survive and hatch Center for Food Security and Public Health, Iowa State University, 2008

  23. Human Transmission • Previously considered non-pathogenic for humans • 1997, Hong Kong • 18 humans infected, 6 died • H5N1 virus linked to outbreak in live bird market and area farms • 2003, the Netherlands • 83 confirmed cases in humans, 1 death • H7N7 strain • Swine are proposed “mixing vessel” Center for Food Security and Public Health, Iowa State University, 2008

  24. Interspecies Transmission of Influenza A Viruses Center for Food Security and Public Health, Iowa State University, 2008

  25. Avian Influenzain Animals

  26. Avian Influenza • Incubation period: 3-14 days • Birds found dead • Drop in egg production • Neurological signs • Depression, anorexia, ruffled feathers • Combs swollen, cyanotic • Conjunctivitis and respiratory signs Center for Food Security and Public Health, Iowa State University, 2008

  27. Post Mortem Lesions • Lesions may be absent with sudden death • Severe congestion of the musculature • Dehydration • Subcutaneous edema of head and neck area Center for Food Security and Public Health, Iowa State University, 2008

  28. Post Mortem Lesions • Nasal and oralcavity discharge • Petechiae onserosal surfaces • Kidneys severely congested • Severe congestion of the conjunctivae Center for Food Security and Public Health, Iowa State University, 2008

  29. Avian Influenza in Cats • H5N1 avian influenza in Asia infected cats fed infected dead chickens • H5N1 experimentally • Respiratory • Systemic disease • Transmits cat to cat Center for Food Security and Public Health, Iowa State University, 2008

  30. Sampling • Before collecting or sending any samples, the proper authorities should be contacted • Samples should only be sent under secure conditions and to authorized laboratories to prevent the spread of the disease • HP AI samples may be zoonotic Center for Food Security and Public Health, Iowa State University, 2008

  31. Diagnosis • Clinically indistinguishablefrom virulent Newcastle Disease (END) • Suspect with: • Sudden death • Drop in egg production • Facial edema, cyanotic combs and wattles • Petechial hemorrhages • Virology and serology necessary for definitive diagnoses Center for Food Security and Public Health, Iowa State University, 2008

  32. Differential Diagnosis • Virulent Newcastle disease • Avian pneumovirus • Infectious laryngotracheitis • Infectious bronchitis • Chlamydia • Mycoplasma • Acute bacterial diseases • Fowl cholera, E. coli infection Center for Food Security and Public Health, Iowa State University, 2008

  33. Diagnosis • Laboratory Tests • HP AI is usually diagnosed by virus isolation • Presence of virus confirmed by • AGID • ELISA • RT-PCR • Serology may be helpful Center for Food Security and Public Health, Iowa State University, 2008

  34. Treatment • No specific treatment • Supportive care and antibiotics for secondary infections • Antivirals (amantadine) effective in reducing mortality • Not approved in food animals • Results in resistant viruses Center for Food Security and Public Health, Iowa State University, 2008

  35. Avian Influenza in Humans

  36. Clinical Signs in Humans • 1997: Hong Kong (H5N1) • Fever, respiratory, vomiting, diarrhea, pain • Fatal cases: severe bilateral pneumonia, liver dysfunction, renal failure, septic shock • 1979: MP AI in harbor seals (H7N7) • Conjunctivitis Center for Food Security and Public Health, Iowa State University, 2008

  37. Clinical Signs in Humans • 2003: Netherlands (H7N7) • Conjunctivitis • Mild influenza or respiratory symptoms • Fatal case: Acute respiratory distress syndrome Center for Food Security and Public Health, Iowa State University, 2008

  38. Avian Influenza in Humans • Risk is low • Strains vary in abilityto infect humans • Close contact with infected birds • High occupational exposure,cultural practices may increase risk • April 2008: 31 cases, 24 deaths Center for Food Security and Public Health, Iowa State University, 2008

  39. H5N1 AI in Poultry, Birds since 2003 Center for Food Security and Public Health, Iowa State University, 2008

  40. Prevention and Control

  41. Recommended Actions • Notification of Authorities • Federal:Area Veterinarian in Charge (AVIC) • www.aphis.usda.gov/vs/area_offices.htm • State veterinarian • www.aphis.usda.gov/vs/sregs/official.htm • Quarantine Center for Food Security and Public Health, Iowa State University, 2008

  42. Recommended Actions • Confirmatory diagnosis • Depopulation may occur • Infected premises • Contact-exposed premises • Contiguous premises Center for Food Security and Public Health, Iowa State University, 2008

  43. Control and Eradication • Eliminate insects and mice • Depopulate flock and destroy carcasses • Remove manure down to bare concrete • High pressure spray to clean equipment and surfaces • Spray with residual disinfectant Center for Food Security and Public Health, Iowa State University, 2008

  44. Prevention • Appropriate biosecurity • Control human traffic • Introduction of new birds into flock • Avoid open range rearing in waterfowl prevalent areas • Education of the poultry industry • Prompt response to MP AI outbreaks Center for Food Security and Public Health, Iowa State University, 2008

  45. Vaccination of Poultry • Emergency situations • Preserve breeding stock • Vaccines • Killed and fowl-pox vectored • DIVA – Differentiating Infected from Vaccinated Animals • US Vaccine bank with 40 mil doses • 20 million for H5 • 20 million for H7 Center for Food Security and Public Health, Iowa State University, 2008

  46. USDA Prevention Activities • Import restrictions • No live birds or bird products from infected countries • Increasing surveillance of wild birds • National H5 and H7 control program • Training for disease recognition • Improving diagnostics for rapid detection Center for Food Security and Public Health, Iowa State University, 2008

  47. Protection of Humans from H5N1 Avian Influenza q q AI ResponsePlan U.S. Border q q Proper food handling and preparation q Surveillance q Food Safety Inspection Service Biosecurity q Avoid contact with poultry Center for Food Security and Public Health, Iowa State University, 2008

  48. Prevention: Humans • Personal Protective Equipment • Gloves, masks • If working with poultry or wild birds • Vaccine • April 17, 2007 • US FDA approved an avian influenza vaccine for humans • Not commercially available • Part of National Strategic Stockpile • For distribution during public health emergency • Antivirals Center for Food Security and Public Health, Iowa State University, 2008

  49. Additional Resources

  50. For More Information • Centers for Disease Control and Prevention (CDC) • http://www.cdc.gov/flu/avian/ • World Health Organization (WHO) • http://www.who.int/csr/disease/avian_influenza/en/ • World Organization for Animal Health (OIE) • www.oie.int • Center for Food Security and Public Health • www.cfsph.iastate.edu Center for Food Security and Public Health, Iowa State University, 2008

More Related