1. Avian Influenza (AI) An Agricultural Perspective
Andrea Morgan, DVM, MS
United States Department of Agriculture
Animal and Plant Health Inspection Service
Veterinary Services
Emergency Management

3. AI Fundamentals

4. The AI Virus
Worldwide, there are many strains of AI virus which can cause varying degrees of illness in poultry
A unique characteristic of influenza viruses is that they are constantly changing or mutating
AI viruses can infect chickens, turkeys, pheasants, quail, ducks, geese, and guinea fowl as well as a wide variety of other birds, including migratory waterfowl
In birds, AI viruses are further divided into two groups: low pathogenic or “low path” (LPAI), and highly pathogenic or “high path” (HPAI)

5. The AI Virus, cont.
Of primary concern is H5N1, a strain of AI virus that has mutated into dozens of high path varieties and has infected humans
To date, 15 countries have confirmed HPAI H5N1 within avian populations (commercial poultry and / or wild)
The 15 countries are: Vietnam, Cambodia, Lao PDR, China, South Korea, Thailand, Japan, Malaysia, Croatia [wild birds only - swans], Indonesia, Kazakhstan, Mongolia [wild birds only], Romania, Russia, and Turkey.
In January 2004, Hong Kong SAR [part of China] also had H5N1 infections confirmed only within wild bird populations.
To date, only Japan, Malaysia, and South Korea have been able to eradicate HPAI H5N1 from poultry

6. The AI Virus, cont.
LPAI signs are typically mild: decreased food consumption, respiratory signs (coughing and sneezing), and a decrease in egg production
Birds with HPAI have a greater level of sickness and may die suddenly. Other clinical signs include lack of energy and appetite and decreased egg production.
The virus can be spread through direct contact between healthy and infected birds, infected fecal matter, and contact with the outer surface of unwashed egg shells

7. The AI Virus, cont. Wild waterfowl are a natural reservoir for AI
Wild ducks sometimes introduce LPAI into domestic flocks raised on a range or in open flight pens through fecal contamination
Once introduced in domestic poultry, LPAI can mutate into a high pathogenic one and cause significant disease. In a poultry house, transfer of the HPAI virus between birds can also occur via airborne secretions.

8. History of HPAI in the U.S.
HPAI has been found in poultry in the United States three times—1924, 1983 and 2004
The 1983 outbreak was the largest, ultimately resulting in the destruction of 17 million birds in Pennsylvania and Virginia before that virus was finally contained and eradicated
By contrast, an isolated HPAI incident in a flock of 6,600 birds in Texas was quickly found and eradicated in 2004

9. The USDA Communication Effort
The United States Department of Agriculture (USDA) and other Federal agencies are communicating and collaborating with Federal public health agencies, including the CDC for preparedness of an AI outbreak by focusing on the following components:
Surveillance
Diagnostics
Response
Recovery

10. Prevention, Surveillance, and Emergency Preparedness

11. Prevention

12. APHIS Efforts to Prevent HPAI
Import restrictions on poultry and poultry products from countries affected by H5N1
Quarantining and testing bird imports
Developing a risk assessment to specifically address the threat of HPAI from Southeast Asia
Increased monitoring of domestic commercial markets for illegal activities
Extensive education and outreach on biosecurity for backyard flocks

13. APHIS Domestic Activities
The President and Congress have approved additional funds to enhance USDA’s AI prevention and preparation efforts. On the domestic front these funds will go in part to:
Increase the current animal vaccine stockpile and stock other response supplies
Enhance preparedness training, surveillance and biosecurity measures to rapidly contain or exclude H5N1 AI virus from poultry farms or premises
Enhance smuggling interdiction and trade compliance
Continue research on AI

14. Biosecurity
APHIS receives support from the U.S. commercial poultry industry in terms of producers’ vigilance in applying and adhering to good biosecurity practices on the farm
“Biosecurity for the Birds” is a major outreach campaign that places informational materials directly into the hands of those raising poultry in their backyards, as well as commercial poultry producers

15. Surveillance

16. Surveillance
APHIS continues to work diligently to keep HPAI from becoming established in the U.S. poultry population
More than one million AI tests are conducted in the U.S. each year
USDA’s Agricultural Research Service developed—and APHIS validated—a rapid test for AI that has proven highly effective in screening for the disease
The test has been distributed to National Animal Health Laboratory Network labs all across the country

17. Surveillance, cont.
The National Poultry Improvement Plan has a program for breeder flocks (in place since 1998) and has established an “AI free” category of certification for commercial companies that require testing flocks for AI
This ongoing program helps commercial companies monitor their breeding flocks for LPAI
State and university laboratories test suspect cases and industry, working with states, conducts export testing at slaughter
States conduct surveillance in areas where AI has historically been a concern (e.g., live bird marketing system)
USDA has also been working closely with State and industry representatives to increase surveillance at live bird markets in the northeastern U.S.

18. Wildlife Monitoring
Biologists within the Department of Interior’s Fish and Wildlife Service and U.S. Geological Survey, as well as USDA, will be sampling migratory birds for H5N1 in the Pacific Flyway starting in April 2006
APHIS’ Wildlife Services has also provided assistance to minimize threats to public and animal health through its National Wildlife Disease Surveillance and Emergency Response Plan

19. Response

20. Incident Command System (ICS)
ICS puts in place personnel and material resources to the site of the incident. APHIS will implement activities in the field in response to any event.
Incident Command Teams will typically be on site within 24 hours of a presumptive diagnosis of AI or any other significant foreign animal disease

21. The ICS Structure