Avian Flu. Tyler Cymet, DO Associate Vice President for Medical Education American Association of Colleges of Osteopathic Medicine

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1 Avian Flu

2 Avian Flu Tyler Cymet, DO Associate Vice President for Medical Education American Association of Colleges of Osteopathic Medicine

4 Outline History of Avian Influenza The hype The reality today The science Public Health Issues Conclusion

5 The Story of Influenza Flu strains are typically found in many mammals Birds and swine are common hosts for what ultimately become human flu viruses Flu thrives in winter but virtually disappears in summer

6 The Story of Influenza Influenza mutates and moves around the globe. Flu hosts usually develop an immunity to the virus after infection.

7 The virus thrives! Flu survives by overcoming seasonal influences and mutating to overcome the immunity in its target population. Individuals who routinely get an annual flu vaccine typically have a higher resistance to emerging flu strains than someone who does not.

8 Viral Mutation Minor mutation in flu virus is referred to as drift. A much bigger immunologic change (mutation) is referred to as a shift.

9 Viral Mutation When there is a Major shift in the immunologic structure it may result in a pandemic. (occurring every years) Pandemic an infectious disease occurring over a wide geographic area targeting a high percentage of the population

10 Avian Flu The current strain of avian flu, H5N1, represents a major shift. When a major shift occurs years after the last exposure: The target population has little or no residual immunity The entire population is a ripe target allowing a large percentage of the population to be infected in the same year

11 Avian Influenza Pathogenicity based on genetic features and/or severity of disease in poultry Low pathogenic AI (LPAI) H1 to H15 subtypes Highly pathogenic AI (HPAI) Some H5 or H7 subtypes LPAI H5 or H7 subtypes can mutate into HPAI

12 The Spanish Flu of million people died worldwide 500,000 deaths in USA

13 Spanish Flu of 1918 Pandemic Young adults did poorly Deaths were mostly directly due to the viral infection, not due to secondary bacterial infection

14 Surge Hospital

15 Mass vaccination facility 1918

History 1878: First identified case in Italy 1924-25: First U.S.

16 History 1878: First identified case in Italy : First U.S. cases Low pathogenic avian influenza first identified mid-twentieth century 1970 s: Migratory waterfowl carriers Outbreaks in mink, seals and whales

17 Avian Flu

18 The usual evolutionary path for most human flu strains Birds usually acquire the influenza virus first The virus then will typically mutate to swine herds Ultimately the virus may then mutate into a form transmissible between humans. Most new human strains arise in areas with dense human and swine populations, with a lot of human-swine contact The swine version usually makes the disease a little more mellow for the next (human) host

19 Evolutionary path (cont.) The transition through swine usually confers typical infection characteristics creating: a self limiting disease, with Mortality limited to the younger and older populations Most deaths due to secondary bacterial infection

20 Avian Flu Medications Currently there is no current vaccine. One company has reported some recent success in developing a vaccine Current antivirals have shown some effectiveness Zanamivir and oseltamivir both act by preventing new viruses from emerging from host cells Resistance has been seen

21 Traits of the Current Avian Flu (H5N1 virus) There has been no passage to the swine population.

22 Traits of the Current Avian Flu (H5N1 virus) Passage directly to humans from birds creates a fear that it will result in a high mortality rate: Target healthy adults the atypical victim group (19-49 years of age) Current mortality rate of > 50% This may be an overestimate Currently it has not mutated to a strain that passes from human to human In rare circumstances it has passed from bird to human Need close and prolonged contact

23 Avian Flu Dynamics Migratory Birds like ducks carry the virus from place to place Chicken farms act as multipliers- more cases in a small space with lots of contact with humans

24 Morbidity/Mortality Approaches 100% in commercial poultry flocks Deaths within 2 to 12 days after first signs of illness Survivors in poor condition

25 The Game Plan Detect bad flu early Surveillance is currently being done by the World Health Organization, Center for Disease Control, and various public health agencies. Stopping the spread of the virus will be critical and is achieved by restricting travel, cancelling public events, engaging in social distancing and keeping people at home.

26 The Game Plan Form a ring around every patient by limiting contact and treating everyone who came in contact with the patient. De-populate local poultry flocks Buy time, vaccinate if available

27 Avian Influenza Pandemic (Dr. Donald A Henderson) A moderate disruption for 16 weeks Maximum of 15% of people ill at any one time No advantage to quarantine or socially isolate people No need to close universities Not enough ventilators, hospital beds, or medical personnel for everyone who might need care

28 The Hype We are overdue We are unprepared Avian flu pandemic is inevitable We are helpless Oseltamivir (antiviral) is the solution

29 Are we overdue? There is no strict time course Pandemics occur once or twice a century but not with predictability Many scares have failed to materialize

30 Is pandemic inevitable? It may happen We can t say no it won t happen

31 What Should We Do? There is much we can do to slow a pandemic

signs Depression, anorexia, ruffled feathers Combs

32 Clinical Signs 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

33 Diagnosis Clinically indistinguishable from virulent Newcastle Disease Suspect with: Sudden death Drop in egg production Facial edema, cyanotic combs and wattles Petechial hemorrhages Virology and serology necessary for definitive diagnoses

34 Diagnosis Laboratory Tests HP AI is usually diagnosed by virus isolation Presence of virus confirmed by AGID ELISA RT-PCR Serology may be helpful

35 Differential Diagnosis Virulent Newcastle disease Avian pneumovirus Infectious laryngotracheitis Infectious bronchitis Chlamydia Mycoplasma Acute bacterial diseases Fowl cholera, E. coli infection

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 in humans in contact

37 Clinical Signs in Humans 2003: Netherlands (H7N7) Conjunctivitis Mild influenza or respiratory symptoms Fatal case: acute respiratory distress syndrome : S.E. Asia, EurAsia

38 Avian Influenza Vaccine Traditional killed vaccines are effective Vaccines will protect only against other avian influenza viruses with the same hemagglutinin (H) type.

39 Economic Impact 1983: U.S. outbreak (H5N2) $65 million in losses Destruction of 17 million birds 30% increase in egg prices : Italy outbreak (H7N1) $100 million in compensation to farmers 18 million birds destroyed Indirect losses of $500 million

40 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

41 Economic Impact 2003: European outbreak (H7N7) Over 33 million birds destroyed ¼ of Netherlands poultry stock Cost? : SE Asia (H5N1) 8 countries >100 million birds destroyed Cost? : SE Asia and Eurasia Spread to Eurasia by migratory birds

42 Is oseltamivir the solution? No, it will also take a concerted public health effort

43 Federal Planning The federal government has created a federal response plan as of 11/1/2005. The most recent federal proposal provides money for Better surveillance Expanded vaccine and medication supplies Specialized Pandemic Plans st Qtr 2nd Qtr 3rd Qtr 4th Qtr East West North

44 Steps YOU can take Practice good personal hygiene: Avoid hand contact with your mouth, eyes, and nose; Wash hands regularly and often with soap and water; Carry a supply of hand sanitizing gel use it regularly after visiting a public restroom; Use paper towels to turn off the faucet and open the restroom doors; Cover your mouth when you cough;

45 Steps YOU can take (cont.) Get a flu shot when offered When flu season arrives avoid contact with infected persons, limit social interactions Be cognizant in public of potentially infected surfaces; Disinfect commonly used surfaces regularly including phones, desktops, keyboards, countertops, etc. Aerosol sanitizers are available. Don t loan your phone or laptop to others

46 Steps YOU can take (cont.) Consider the wearing of an N95 respirator and/or disposable gloves when going out in public; Set aside a supply of food to limit your need to eat in public; Maintain a supply of electrolyte drinks such as Gatorade to combat dehydration should you get the flu Stay informed information on the status of avian flu is available on a number of websites

47 Steps YOU can take (cont.) When you are in public be aware of potential health issues such as the glass of water that is served but the server has their fingers on the inside or rim of the glass. Avoid the use of public pay phones and be alert to other surfaces in public which may be contaminated check out counters, door knobs, handshakes. Commons sense will go a long way to eliminating many of the potential sources for you to get the flu.

48 In Conclusion Avian flu is currently a bird disease With a lot of potential There is no need to panic But it is worthy of more planning

49 Internet Resources World Organization for Animal Health (OIE) USAHA Foreign Animal Diseases The Gray Book World Health Organization

50 Additional Resources CDC Centers for Disease Control and Prevention Avian influenza (bird flu) home page U.S. Department of Agriculture Biosecurity for the birds Avian influenza

INFLUENZA-2 Avian Influenza

INFLUENZA-2 Avian Influenza VL 7 Dec. 9 th 2013 Mohammed El-Khateeb Overview 1. Background Information 2. Origin/History 3. Brief overview of genome structure 4. Geographical Distribution 5. Pandemic Nature