Highly Pathogenic Avian Influenza

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Highly Pathogenic Avian Influenza

• Threats to Biodiversity Conservation in Africa

College of African Wildlife Management Mweka,
Tanzania July 2008
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Overview

• Highly Pathogenic Avian Influenza
• Introduction History
• Current Threat
• Potential Impacts on Biodiversity Conservation
• Preparedness and Response
• Global Avian Influenza Network for Surveillance
  (GAINS)

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Influenza A Virus

• Three types of Influenza A virus
• Seasonal Influenza
• Widely circulating amongst humans (cause of the
  flu)
• Avian Influenza
• Primarily infects birds, but other mammalian
  species (including humans) susceptible
• Low Pathogenicity
• High Pathogenicity (H5N1)
• Pandemic Influenza
• Virus with the capacity for efficient, sustained
  human to human transmission

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Influenza A Virus

• Typified by two types of surface proteins
• Hemagglutinin (HA)
• Neuraminidase (NA)
• No cross immunity between seasonal and avian
  influenza

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Highly Pathogenic Avian Influenza

• HPAI defined based upon high mortality rates in
  domestic poultry
• H5N1 is the currently circulating HPAI strain

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H5N1 HPAI

• First Identified in 1996 in Guangdong, China
• Initial outbreak in domestic poultry 1997, Hong
  Kong
• 1.5 million chickens culled
• 18 people infected 6 died
• Reemergence in Hong Kong in February 2003

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Historical Influenza Pandemics

• 20th century pandemics
• 1918 (50 million deaths globally)
• 1957 (1 million)
• 1968 (750,000)

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Belshe RB. N Engl J Med 200535321
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Pandemic InfluenzaImpacts

• Pandemic influenza poses significant public
  health risk
• No pre-existing immunity to H5N1 in human
  population
• Isolates have demonstrated some anti-viral
  resistance
• Vaccine has been developed, but may not cover
  pandemic strain
• Difficulty of containment
• Projected Pandemic Costs
• 10-180 million deaths worldwide
• Economic Impact 2-3.1 of global GDP (gt2
  trillion USD) (World Bank)

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Highly Pathogenic Avian Influenza

• Bird to Bird Transmission
• Predominant type of transmission to date
• Primarily still a disease of birds
• Viral spread via trade in poultry and poultry
  products
• Via trade in caged/exotic birds
• Via human movement
• Via wild birds
• The relative importance of wild birds in
  transmission varies by situation
• Research indicates HUMAN MOVEMENT and TRADE are
  the most common sources of viral transmission

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Highly Pathogenic Avian Influenza

• Bird to Human Transmission
• Rare
• Usually a result of very close contact with
  infected poultry and infected blood/tissues or
  contaminated surfaces
• Human to Human Transmission
• Isolated instances suspected (Thailand, 2004)
• No sustained human to human transmission to date

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H5N1 Distribution

• Poultry
• H5N1 in domestic poultry in Asia, Africa,
  Pacific, Europe and Near East
• Considered endemic in parts of Asia and Africa
• gt240 million bird deaths
• H5N1 case mortality rate in domestic poultry
  90-100 in 48 hours
• Humans
• H5N1 confirmed cases in Asia, Africa, and Near
  East
• 2003-2008 378 cases 238 deaths
• Case mortality in humans 60

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H5N1 Influenza Avian Case Distribution
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H5N1 Influenza Avian Case Distribution
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H5N1 InfluenzaHuman Case Distribution
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H5N1 in Africa

• February 2006, H5N1 first identified in
  commercial poultry in Africa (Nigeria and Egypt)
• April 2007, H5N1 identified in Ghana and Togo

Poultry Wild birds Captive Birds Humans
FAO
Countries with H5N1 presence in birds (as of
Sept. 2007)
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Poultry Density and CIRAD Wild Duck Telemetry
Locations in Africa as of June 30, 2008
CIRAD
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H5N1 East Africa

• Currently H5N1
• Egypt
• Djibouti
• Sudan
• Somalia (?)
• Currently H5N1 Free
• Kenya
• Tanzania
• Uganda
• Ethiopia

• Risks
• Introduction to HPAI free countries via poultry
  trade, human movement, migratory birds
• Prevention
• Active, ongoing monitoring surveillance
• Trade restrictions with positive countries
• Bolstered inspection at ports of entry
• Emergency preparedness and response plans ready
  to be mobilized

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Kenya Red Cross
Rift Valley Falls Along Europe/Southern Africa
Migratory Route Peak Migration Mid September -
Mid November
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HPAI Poultry Consumption

• Loss of Domestic Poultry
• Poultry illness/loss of productivity
• Poultry death
• Poultry culls

Irrational Poultry Consumption Fears
Kenya 30 million chickens, 80 raised
traditionally by small holders 2-3
chickens/rural household

• Loss of income
• Inability to pay for school fees, medicine,
  dietary staples
• Loss of protein nutrition

Tanzania 27 million chickens, 70 raised
traditionally by small holders
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FAO/C.Squarzoni
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Impacts on Biodiversity Conservation

• Threats
• Health of wild birds
• May 2005, Qinghai Lake National Nature Reserve
  (China) H5N1 outbreak estimates of 5-10 of
  worlds population of Bar-headed Geese (Anser
  indicus) succumbed to AI virus
• Communities may turn to bush meat for protein
  requirements
• Fear may incite wild bird culls or
  wetlands/nesting area destruction

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Biodiversity ConservationOpportunities

• Accurate information dissemination is essential
• Targeting local communities, park staff, media
  and human animal health workers
• Sound, science-based policy decisions
• Wetlands and protected area preservation
• Will help limit number of displaced wild birds
  forced into contact with humans and domestic
  poultry

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Alternative Protein Sources
MEAT Cattle Buffalo Pig Sheep Goat Fish

• Communities should be prepared to draw on
  alternative protein sources to hedge against
  catastrophic poultry loss
• Diversified, Site-Appropriate Livestock Portfolio

DAIRY Cattle Sheep Goat
PROTEIN RICH VEGETABLE Peanut Soy
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Avian InfluenzaPreparedness Response

• Surveillance
• Communication Education
• Diagnostic Capacity Commodity Distribution
• Research
• Rapid Response Containment

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Surveillance

• Early detection is critical for containment
• Transparent reporting
• Donor resources need to be made available for
  active surveillance
• CDCs Global Disease Detection Center (Kenya)
• Army Medical Research Unit (Kenya)

International Scientific Task Force on Avian
Influenza
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Wild Bird Global Avian Influenza Network for
Surveillance (GAINS)

• Program managed by Wildlife Conservation Society,
  funded by USAID
• Global surveillance monitoring system
• Applicable to other diseases, including wildlife
  disease
• Sharing of near real-time HPAI monitoring in wild
  birds using an accessible online format
• Tracks genetic changes in the virus
• Encourages transparent disease reporting
• Technical support to national laboratories/vet
  services for surveillance and diagnostic
  activities

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Global Avian Influenza Network for Surveillance

• Target Audiences
• Government
• Local Communities
• Policy Makers
• Private Sector
• Informs decision making to cope with threat of
  HPAI at local through national levels
• Serves as an early warning system for HPAI
  emergence
• Potential to limit risks to human health,
  wildlife health, domestic poultry/livelihoods

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Global Avian Influenza Network for Surveillance
GAINS Global Surveillance Locations

• Wild Bird Flyways
• Upcoming work will use sat transmitters to define
  the Nile-Rift Valley flyway

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• Data
• Positive Cases
• Total Sampled Cases
• Wild Bird Counts

• Parameters
• Dates
• Location
• Wild Bird Species
• H N type
• Pathogenicity

WISDOM Map Explorer
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Communication Education

• Prevention Strategies
• Recognizing Illness
• Discouraging Consumption of Sick Poultry
• Farm/Village Biosecurity
• Slaughter and Cooking Precautions
• Behavior Change Communication (i.e. hand washing,
  personal hygiene)

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Communication Education

• Preventing Wild Bird Poultry
  Transmission
• Domestic poultry should not be permitted to
  commingle with wild birds
• Care taken to avoid shared water sources
• Fencing or covered sheds
• Improved husbandry practices (All In-All Out)
• Biosecurity on farms, in households, at markets,
  and during transport

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Communication Education

• Enforcement of the illicit wild bird trade

CDC
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Diagnostic Capacity Commodity Distribution

• Personal Protective Equipment
• Goggles, Aprons, Gloves, Boots
• Diagnostic Kits/Reagents
• Capacity Building for National Laboratory
  Diagnosis Epidemiological Surveillance
• Response Preparation
• Disinfectants, etc

DAI
Synbiotics
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Research

• Wild Birds
• Can we clarify their role in transmission?
• Migratory flyways need to be defined
• Which species may be inapparent carriers? Do some
  species exhibit high mortality rates?
• Banding, bird counts, telemetry

• Disease Ecology
• How persistent is the virus in the environment?

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FAO
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FAO
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Research Development

• Vaccination
• Poultry
• Vaccine available policy on use varies by nation
• Reduced morbidity and mortality, however viral
  shedding still possible in vaccinated poultry
• Human
• April 2007, US FDA approved H5N1 human vaccine
  (Sanofi Pasteur, Inc.)
• Emergency stockpiles only not commercially
  available
• Future pandemic influenza strain unknown, so
  vaccine efficacy questionable

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Response Containment

• Emergency response plans in place
• Centrally coordinated effort drawing on diverse
  stakeholders
• Table and field-tested plans
• Adequate resources for culling and disposal
• Compensation plans fair, transparent, and fully
  funded

FAO
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Additional Resources

• News Updated Information
• CIDRAP www.cidrap.umn.edu
• ProMED Mail www.promedmail.org
• Centers for Disease Control and Prevention
  www.cdc.gov

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Additional Resources

• Multi and Bilateral Efforts
• United States Agency for International
  Development www.usaid.gov
• World Health Organization www.who.int
• UN, Food and Agriculture Organization
  http//www.fao.org/avianflu/en/index.html
• Including OFFLU and EMPRES
• World Organization for Animal Health
  http//www.oie.int/eng/info_ev/en_AI_avianinfluenz
  a.htm

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Additional Resources

• Monitoring Surveillance
• Global Avian Influenza Network for Surveillance
  (WCS) www.gains.org
• Educational Communication Resources
• InterAction http//www.interaction.org/disaster/av
  ian/index.html
• Academy for Educational Development
  http//avianflu.aed.org/index.htm