Avian Influenza: Outbreak in Spring 2015 and Preparing for Fall

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1 Avian Influenza: Outbreak in Spring 2015 and reparing for Fall James A. Roth, DVM, hd Center for Food Security and ublic Health College of Veterinary Medicine Iowa State University

2 Topics for Today Understanding key properties of influenza viruses How did the H5N2 virus get to Iowa? Characteristics of and response to the current outbreak reparedness for a potential return of the virus during the next flu season

3 High ath Avian Influenza Outbreak

4 Canine Influenza Outbreak

5 Understanding Key roperties of Influenza Viruses

6 Influenza A Virus Enveloped RNA virus: 8 segments, H and N are coded for by different segments 16 hemagglutinins Important for attachment to host cell 9 neuraminidase Important for virus release from host cell

7 Influenza Antigenic Drift oint mutations in H and/or N H and N remain the same numbers but they are different than the original May result in decreased immunity, antibody does not bind as well Antigenic drift is the cause of seasonal epidemics

9 Influenza Antigenic Shift Emergence of a new subtype (change in H and/or N type) Example: H3N2 to H5N1 No immunity, therefore causes pandemics Mechanisms Direct transmission animal to human Genetic reassortment in a population Re-emergence of virus in a species

11 Influenza A Reservoir ild waterfowl and migrating birds are reservoir All avian influenza viruses are type A All H and N types - low pathogenicity in waterfowl

12 Interspecies Transmission H3N2 H4N5, H13N9 H3N8 H3N2 H1N1 H1N2 All H5N1* H3N2 H1N1 H5N1* H5N1 H7N9, H5N2, etc H7N9* Ferrets * Rare occurrences

13 Zoonotic Influenza Avian influenza in humans: sporadic infections, some fatal H5N1, H7N9, H7N7 Not in this hemisphere Swine influenza in humans CDC reported 31 cases from rior to 2005: 1 case every 1-2 years H3N2 306 cases mostly in visitors to fairs, 2012 Ferrets Can be infected by humans and vice versa Equine No reports of clinical cases caused by natural exposure Canine No reports of clinical cases caused by natural exposure Center for Food Security and ublic Health, Iowa State University CVM, 2011

14 Risk Factors for Influenza Disease

15 Risk Factors for Influenza Disease

16 High athogenicity vs Low athogenicity Avian Influenza LAI- asymptomatic to mild infection HAI can have 100% morbidity and mortality, many body systems affected

17 High athogenicity vs Low athogenicity Avian Influenza HAI: An H5 or H7 with specific genetics and/or high lethality Any non H5 or H7 with high lethality LAI: Any H type including H5 or H7 No or mild clinical signs Infection localized

18 How did the H5N2 avian influenza virus get to Iowa?

19 H5N1 Avian Influenza 2004/5 H5N1 emerged in Asia, killed millions of poultry and is zoonotic Concern that H5N1 would spread through migrating waterfowl from flyways in Europe/Asia to the estern hemisphere Extensive surveillance programs established in U.S. No detections of this strain of H5N1 in estern hemisphere New strains of H5 avian influenza detected in Canada and US fall 2014 Not zoonotic

20 H5 HAI reports from East Asia September 2014 through April 8, 2015 (OIE) Eastern Asia Reports of H5 HAI subsided in the region during summer Then in September, outbreaks of H5N1, H5N2, H5N6, H5N8 HAI occurred in China. Original H5N8 outbreak occurred January- April, 2014, most intensely in S. Korea and Japan. After 5 months with no reported cases, H5N8 was detected again, 24 September, in S. Korean commercial poultry. It was detected again in Japan in November. H5N2, H5N3, H5N8 outbreaks occurred in Taiwan in early H5N1 in wild birds H5N1 in poultry H5N2 in wild birds H5N2 in poultry H5N3 in wild birds H5N3 in poultry H5N6 in wild birds H5N6 in poultry H5N8 in wild birds H5N8 in poultry

21 H5 HAI reports from North America November 2014 through April 8, 2015 (OIE) North America H5N2 first isolated 30 November 2014 from commercial poultry in British Columbia; outbreak continues into H5N8 first isolated 10 December 2014 from captive wild birds in ashington; later isolated from backyard poultry in Oregon. Similarly, H5N2 identified in US wild birds and backyard poultry. H5N1 first isolated 29 December 2014 from wild duck in ashington. H5N8 isolated 19 January 2015 from commercial turkey farm in California. H5N2 detected in poultry in South Dakota, Minnesota, Missouri, Arkansas, and Kansas in March 2015 and Ontario, Canada in April H5N1 in wild birds H5N1 in poultry H5N2 in wild birds H5N2 in poultry estern Europe H5N8 first isolated 4 November 2014 from commercial poultry in Germany; also isolated in November from a wild duck. By mid-december, H5N8 was isolated from commercial poultry in The Netherlands, United Kingdom, and Italy. H5N3 in wild birds H5N3 in poultry Eastern Asia H5N6 in wild birds H5N6 in poultry Reports of H5 HAI subsided in the region during summer Then in September, outbreaks of H5N1, H5N2, H5N6, H5N8 HAI occurred in China. Original H5N8 outbreak occurred January- April, 2014, most intensely in S. Korea and Japan. After 5 months with no reported cases, H5N8 was detected again, 24 September, in S. Korean commercial poultry. It was detected again in Japan in November. H5N2, H5N3, H5N8 outbreaks occurred in Taiwan in early H5N8 in wild birds H5N8 in poultry

22 H5 HAI reports from North America November 2014 through April 8, 2015 (OIE) East Atlantic flyway Migratory aquatic birds also the likely mode for H5N8 HAI virus spread to North America Eurasian (EA) H5N8 was likely carried to Alaska by infected birds migrating on the East Asia / Australia flyway. ithin 3 months, HAI viruses were detected in the acific Americas flyway and the Mississippi/Central Americas flyway. EA H5N8 underwent gene reassortment with low pathogenicity avian influenza (LAI) strains endemic to North American wild birds. This means a bird was co-infected at some point with the H5N8 and an American (AM) LAI strain, enabling the 8 gene segments to be mixed and matched in new combinations. EA/AM H5N1 and EA/AM H5N2 isolates in the western and central US were reassortants that contained genes of North American and Eurasian origin. H5N1 in wild birds H5N1 in poultry H5N2 in wild birds H5N2 in poultry H5N3 in wild birds H5N3 in poultry H5N6 in wild birds H5N6 in poultry H5N8 in wild birds H5N8 in poultry

23 Characteristics of the current HAI outbreak

24 Figure 1. All HAI Detections As Of May 13, 2015 M (as reported on *one or more detections may have occurred in county

25 Figure 7. remises Detected for ALL STATES Including ILD BIRD detections from 12/8/2015 to 7/2/2015 By EEK ild Bird Detections in the acific Flyway First Detection in a Commercial Flock in California First Detection in Commercial Minnesota Flock ild Bird Detections in the Central/ Mississippi Flyways First Detection in Commercial Iowa Flock ild Bird (acific) Commercial (acific) Captive ild (acific) Backyard (acific) ild Bird (Central/Miss) Commercial (Central/Miss) Backyard (Central/Miss) Earliest available date indicating clinical signs is used for figure. For most premises, this is the date of clinical signs, a suspect status, or a presumptive positive status. Some premises may only have a confirmed positive status date. 320 detections (4 captive wild bird; 21 backyard flocks; 211 commercial flocks; 84 wild birds). o Only full weeks (7 days) are pictured; in addition to the dates pictured, there have been no detections after 6/28/2015. o All captive bird, backyard flock, and commercial flock data are from EMRS. o ild bird dates are based on date of collection, from USDA/USGS/National Flyway Council data. o This represents 80% of the captive bird detections, 100% of all other detections. o Figures may change slightly as data is added to EMRS (e.g., date of clinical signs). 2 5

26 Iowa oultry roduction In March 2015: Iowa had 59.5 million egg layer chickens in 3,821 laying facilities (1 st in US egg production) 16.5 billion eggs produced annually (17% of national production) Raise over 11 million turkeys (9th in US turkey production) on about 200 farm sites

27 Highly athogenic H5N2 Avian Influenza in Iowa Total oultry Affected (6/8/2015) 31,502,052 April 13 to June 16, 2015 Layers 24,725,086 ullets 5,624,336 Turkeys 1,128, infected sites 6 Backyard sites 71 Commercial sites Hatchery 18,791 Backyard Flocks 5,110

28 reparedness for Avian Influenza Secure Egg Supply lan Biosecurity Vaccination??

29 Control Area Established Around Each Infected remises Infected Zone = 3 km, Buffer Zone =10 km (6.2 mile radius = 120 sq. miles) Quarantine, all poultry inspected Movement by permit only

30 Response to an Infected remises Biosecurity Depopulation of all houses on premises Euthanasia Foam, CO2 Disposal Incineration Burial Composting Land Fill Cleaning and disinfection Remove quarantine and allow re-stocking

31 Secure Egg Supply lan Designed to enable movement of eggs from non-infected premises in a Control Area: Audited biosecurity steps Surveillance: Daily CR testing of pharyngeal swabs Epidemiology questionnaires Daily reporting of flock mortality and egg production Movement permits issued by state and federal authorities

32 Biosecurity to Control Introduction of Avian Influenza The structural and operational biosecurity of large caged layer facilities has proven to be effective for control of endemic diseases, has enabled the production of eggs to be profitable for producers, available at a low cost for consumers, and has helped provide an economic engine for communities. However, the current level of biosecurity has failed to protect these facilities from the highly pathogenic H5N2 avian influenza virus.

33 Layer facility with approximately 4 million hens Google Earth View Egg breaker for production of liquid eggs (70% of eggs produced in Iowa are liquid eggs)

35 Biosecurity to Control Introduction of Avian Influenza otential sources of avian influenza virus Unfiltered air Contaminated feed Migrating waterfowl and their feces ater contaminated by waterfowl feces Flies and other insects Sparrows, starlings, and other birds Rodents Contaminated fomites

36 Vaccination as a Tool for Control of Avian Influenza Vaccine is specific for the strain of virus in the vaccine and closely related strains. The current HAI virus can drift so that the vaccine has reduced efficacy, or it can shift so that the vaccine is not effective.

37 Vaccination as a Tool for Control of Avian Influenza Vaccinated flocks can still become infected. Clinical signs may be greatly reduced, but the virus can still replicate and mutate The flock will still need to be depopulated to destroy the virus.

38 Vaccination as a Tool for Control of Avian Influenza New strains of either high or low pathogenicity avian influenza virus can be introduced in vaccinated birds resulting in the need to depopulate Vaccination for HAI will result in the loss of most export markets for all poultry and uncooked products

39 Vaccination as a Tool for Control of Avian Influenza The next strain of avian influenza virus may be zoonotic (e.g. Asian strains of H5N1, H7N7, or H7N9), greatly complicating the response effort. A vaccine for the current H5N2 virus would not protect against these zoonotic strains of avian influenza

40 Comments and Questions: he Gentle Doctor by Christian etersen, 1938

High Pathogenic Avian Influenza

High Pathogenic Avian Influenza High athogenic Avian Influenza Dr. Jack Shere Associate Deputy Administrator U.S. Department of Agriculture Animal and lant Health Inspection Service Veterinary Services NIAA Annual Meeting 1 HAI History