So Far

• Primarily an Avian Disease• Considering geographic spread and lethality

in birds – very little human disease• Fear that the virus may develop the ability

to be easily passed on from person to person• Not clear if H5N1 can be the next pandemic

strain• Necessitates preparedness

Avian Influenza (H5N1) Human Disease

• 2003- 21 Feb 2006 180 total cases with 100 deaths – Human disease in China, Indonesia, Viet Nam,

Thailand, Cambodia, Turkey, Iraq, Azerbaijan.

• No confirmed human-to-human transmission

• All recent cases associated with intimate contact with diseased birds

Current Transmission Risk

• Human risk is associated with contact with diseased birds, ingestion of poorly cooked or raw infected poultry meat or blood, contact with contaminated water.

• If Avian disease (not pandemic) comes to the US– Avoid contact with sick or dead birds

– Avoid open markets with live birds

– Eat only approved sources of poultry (USDA)

– Fully cook poultry

H5N1

• Mortality associated with:– Paucity of postmortem data

• bacterial pneumonia

• viral pneumonias

• cytokine storm

• coagulopathy.

Current ThreatContainment Problems

• 75-80% poultry farms are small backyard operations - limits biosecurity

• Numerous endemic viruses resulting in 50-70% baseline poultry deaths

• Multiple disincentives to report a die-off– Fear– Distrust– Poor or no reimbursement– Attachment

Continued containment problems

• Uncertain transparency– H5N1 has been circulating in China for at least a

decade• Not reported because information on epidemics of High Path

AI were State secrets until 2003

• Currently one laboratory in China has permission to conduct AI research

– H5N1 noted in PRC veterinary sources before 1997

– Improving

Containment Problems

• Most countries lack comprehensive surveillance or response plans– Lack short, intermediate or long term plans or

needs assessment– Poor coordination between Ministries of

Agriculture and Health result in inability to assess true capabilities and needs

Containment Problems

• Donor coordination needs improvement– Multiple site evaluations hinder host nation

response– Improved communication between donors

needed to coordinate relief measures

• FAO – Lacks capacity to provide rapid response and

hands on assistance and training

Good News!

• Turkey- exception to the region– Excellent response– Transparency– Will serve as a model for the region– Looking ahead to control measures after

repopulation of domestic poultry population– Working with WHO & World Bank to change

backyard poultry practices to increase biosecurity

US Risk

• 3 Million registered fighting cocks in CA• 9.3 Billion commercial chickens - good

biosecurity• 100 Million chickens in unregulated live bird

market – not so good biosecurity• 60 Million foreign visitors to the US• 60 Million US visitors to foreign countries• 400 Million crossings in from Mexico• Fomite in Viet Nam can be in Boise in two flights

RESPONSE

Containment Measures

• Antivirals are not the magic bullet • Best measures are public health

– Sneeze and cough etiquette– Hand washing– Tele-commuting if possible– If in a rural area consider closing schools– Social distancing– Daily temperature monitoring – If sick - stay at home– Flu hot lines, triage, early treatment if needed– Risk communication

Antivirals

• Tamiflu– Adult & pediatric formulations – pediatric

compounding instructions now available– Anecdotal and animal data demonstrates efficacy

and effectiveness for treatment of current H5N1– Resistance documented for Type A influenza

• 4% adults, up to 20% pediatrics• Resistant mutation results in virus that is either

incapable of or has decreased infectivity

Antivirals

• Relenza– May result in less or no resistance but has not

been used to date for H5N1– Limited per FDA to treatment only– Contraindicated in those with history of

reactive airway disease– Requires education/psychomotor skills

• Amantadines – of no use for H5N1

Vaccine

• HHS stockpile of Avian influenza (H5N1) vaccine– Vaccine is based on 2004 Vietnamese clade

– Little cross reactivity to Indonesian Clade (Clade 2)

– Based on 90ug dose requirement• Dosage may be reduced pending adjuvant and other

antigen sparing strategies

– Currently in bulk storage (6 week fill requirement)

– Clade 2 vaccine development approved

– Other Clade 1 vaccines in development

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WWW.pandemicflu.gov