1. Detecting and Preventing Disease - Introduction
Worldwide, END and HPAI have been responsible for devastating disease outbreaks in commercial poultry production as well as in backyard flocks. The U.S. and other countries with modern production systems control such outbreaks through government programs that relate to trade restrictions and the destruction of infected flocks.
By the end of this lesson, you will be able to:
Define the causative agents of diseases
Define how a virus operates and spreads in the environment
Discuss one example of how an outbreak of disease in animal agriculture impacts the economy
Understand the difference between an animal carrying a disease agent and exhibiting the clinical signs
Define and list the actions to take if the clinical signs of END and AI are recognized
Identify the clinical signs for END and AI in poultry
Know what to do to prevent the spread of END and AI
Audio Script: We know that END and HPAI are responsible for devastating poultry disease outbreaks. The United States and other countries use modern production systems to control such outbreaks. Governments help by placing trade restrictions against countries with diseases such as HPAI and END.

2. Causative Agents and Signs of END
Exotic Newcastle Disease:
Is a contagious and fatal viral disease
Affects all species of birds
Is so deadly that many birds die without showing any signs of disease
Can be found worldwide
Clinical Signs of END
END affects your birds' respiratory, nervous and digestive systems. The incubation period for the disease ranges from 2 to 15 days. An infected bird may show the following signs:
Sneezing, gasping for air, nasal discharge and coughing
Greenish, watery diarrhea
Depression, muscular tremors, drooping wings, twisting of head and neck, circling and
complete paralysis
Egg production may either drop partially or stop completely
Production of thin-shelled eggs
Swollen tissues around the birds' eyes and neck
Sudden death
Increased flock deaths
Audio Script: Let's begin by learning about exotic Newcastle disease or END. What causes END? END is a contagious and fatal viral disease that affects all bird species. It is probably one of the most infectious poultry diseases in the world. END is so deadly that many birds die without showing any signs of disease. In unvaccinated poultry flocks, a death rate of almost 100 percent can occur.

3. How END Spreads
END spreads chiefly through the bodily discharges of infected birds to healthy birds. It
spreads rapidly among birds kept in confinement, such as commercially raised chickens.
Because high concentrations of the END virus are in bodily discharges of birds, the disease
also can be spread easily by people and equipment.
Mechanical means
Tractor
Truck
Shovels
Buckets
Farm owners and visitors
Non-Mechanical means
Shoes and clothing
The droppings of infected birds
Secretions from the nose, mouth and eyes of infected birds
Survival Period of the END Virus:
This virus can survive in a warm and humid environment for several weeks. This environment
could be birds' feathers, manure and other materials.
Audio Narration: END spreads chiefly through direct contact between healthy birds and the bodily discharges of infected birds. It also spreads rapidly among birds kept in confinement, such as commercially raised chickens. High concentrations of the END virus are in the bodily discharges of birds. Therefore, the disease can be spread easily by mechanical means.

4. Causative Agents and Signs of AI
Domestic poultry is vulnerable to avian influenza (AI). Most AI strains are classified as low pathogenicity avian influenza (LPAI), and cause few clinical signs in infected birds. In contrast, high pathogenicity avian influenza (HPAI) causes a severe and extremely contagious illness and death among infected birds.
Clinical Signs of AI
The clinical signs of birds affected with all forms of AI may show one or more of the following:
Sudden death without clinical signs
Lack of energy and appetite
Decreased egg production
Soft-shelled or misshapen eggs
Swelling of the head, eyelids, comb, wattles and hocks
Purple discoloration of the wattles, combs and legs
Nasal discharge
Coughing and sneezing
Lack of neural coordination
Audio Script: Avian Influenza (AI) is a contagious disease that can infect a wide variety of domestic and wild birds. There are different strains or subtypes of AI viruses. LPAI can cause little or no signs of illness in poultry, while HPAI can cause severe illness with high death losses.

5. Classification of AI
Based on the severity of the illness they cause, AI viruses can be classified into:
High Pathogenicity (HPAI) form: This is a very infectious and fatal form of the
disease that, once established, can spread rapidly from flock to flock. HPAI can lead
to high mortality
Low Pathogenicity (LPAI) form: Here, under field conditions, virus strains are
capable of mutating into HPAI viruses, which lead to greater illness among infected
birds
Audio Script: Based on the severity of the illness they cause, AI viruses can be classified into Low-Pathogenicity (LPAI) and High-Pathogenicity (HPAI)

6. How AI Spreads
AI viruses are spread through:
Exposure of poultry to waterfowl
Illegal movement of poultry
Contaminated poultry equipment, manure, vehicles, egg flats, crates and people
whose clothing or shoes have come in contact with the virus
Audio Script: AI is spread through:
The exposure of poultry to waterfowl and
The illegal movement of poultry, poultry equipment and people worldwide
Once introduced, the disease can be spread from bird to bird by direct contact. Manure, equipment, vehicles, egg flats, crates and people whose clothing or shoes have come in contact with the virus can also spread it.

7. Be Alert! Birds Can Look Healthy But Be Carrying Disease
Birds can appear healthy, yet be carrying a virus. For example, psittacine birds, such as parrots, can carry the END virus, yet not show clinical signs.
Birds with low-path AI may appear healthy or have mild illness, however, LPAI can cause mild clinical signs such as some facial swelling, respiratory signs, and a slight drop in egg production.
Birds with high-path AI usually have visual clues (such as nasal discharge and lack of energy and appetite) that indicate they are sick. Sudden deaths are another indication of HPAI.
Audio Script: In order to prevent animal diseases from spreading, it's important for you to know how to differentiate between an animal carrying a disease agent and one exhibiting clinical signs. Birds with low-pathogenicity avian influenza may only have mild illness, whereas birds with high-pathogenicity avian influenza almost always have some visual clues (such as nasal discharge, coughing or sneezing) that indicate they are sick.

8. Preventing an Outbreak of HPAI
To prevent an outbreak of HPAI on your farm, poultry producers should practice biosecurity
measures. These are some sound biosecurity practices:
Keep Your Distance:
Restrict access to your property and your birds
Consider fencing off the area where you keep your birds and make a barrier area if
possible. Allow only people who take care of your birds to come in contact with them
If visitors have birds of their own, do not let them near your birds
Game birds and migratory waterfowl should not have contact with your flock because they
can carry germs and diseases
Keep It Clean:
Wear clean clothes. Scrub your shoes with disinfectant
Wash your hands thoroughly before entering your bird area
Clean cages and change food and water daily
Clean and disinfect equipment that comes into contact with your birds or their droppings,
including cages and tools
Remove manure before disinfecting
Properly dispose of dead birds
Audio script: Most AI virus strains are of low pathogenicity and typically cause few or no clinical signs in infected birds.
LPAI viruses are capable of mutating under field conditions into HPAI viruses which lead to severe illness among infected birds, and death.
The USDA's Animal and Plant Health Inspection Service or APHIS, works to keep HPAI from becoming established in the U.S. poultry population.

9. Don't Haul Disease Home:
If you have been near other birds or bird owners, such as at a feed store, clean and
disinfect car and truck tires, poultry cages and equipment before going home
Have your birds been to a fair or exhibition? Keep them separated from the rest of your
flock for at least two weeks after the event
New birds should be kept separate from your flock for at least 30 days
Don't Borrow Disease From Your Neighbor:
Do not share lawn and garden equipment, tools, or poultry supplies with your neighbors or other bird owners
If you do bring these items home, clean and disinfect them before they reach your property

10. Know the Warning Signs of Infectious Bird Diseases
Sudden increase in bird deaths in your flock
Sneezing, grasping for air, coughing and nasal discharge
Watery and green diarrhea
Lack of energy and poor appetite
Drop in egg production or soft- or thin-shelled, misshapen eggs
Swelling around the eyes, neck, and head
Purple discoloration of the wattles, combs, and legs (AI)
Tremors, drooping wings, circling, twisting of the head and neck, or lack of
movement (END)
Early detection is important to prevent the spread of disease.
Report Sick Birds
Don't wait. If your birds are sick or dying call:
Your local cooperative extension office, or
Local veterinarian, or
The state veterinarian, or state animal diagnostic laboratory, or
U.S. Department of Agriculture
(USDA) Veterinary Services office:
- Toll-free hotline ( )
- There is no charge for this service

11. AI and Human Health
For information about AI and human health, see the Centers for Disease Control website at
Audio Script: Typically, AI viruses do not infect humans. The Centers for Disease Control maintains an extensive website with information about avian influenza.

12. END and Human Health
END:
Is only an avian disease
Is not a threat to human health
May cause mild conjunctivitis for about two or three days
Audio Scripts: END is a bird disease only, and poses no threat to human health. On occasion, humans can get a mild form of conjunctivitis from contact with contaminated birds or surfaces.

13. Types of Birds Affected by END and AI
END is contagious and can kill all species of birds. It is one of the most infectious poultry diseases in the world.
Poultry hobbyists and owners of pet birds should be especially careful. Birds illegally smuggled into the United States are not quarantined and tested by the USDA and therefore may carry the END virus. If you buy a pet bird be sure to request certification that the bird has been legally imported or is of U.S. stock.
Birds Affected by AI
AI viruses can infect chickens, turkeys, pheasants, quail, ducks, geese, guinea fowl as well as
a wide variety of other birds. Migratory waterfowl can be infected with AI and END.
Audio Script: END and AI are contagious and can infect many avian species.

14. Economic Impact of Major Poultry Diseases
California
(END):
11.9 million birds either died or were destroyed
Cost: $56 million
(END):
3.4 million birds either died or were euthanized
Nationwide cost: $170 million
5,352 federal employees, 2,338 state and local employees
Pennsylvania
1983 outbreak (mutated to highly pathogenic strain - H5N2):
22 million birds
Over $100 million
2001 outbreak of low-pathogenic H7N2 avian flu:
140,000 birds
$350,000
Florida
1980 (END):
8,000 cage birds died
30,307 birds had to be euthanized in 23 states
Cost: $1.66 million
Audio Script: A major outbreak of HPAI or END could cost the poultry industry, consumers and taxpayers dearly in terms of poultry losses, trade opportunities, and financial losses to the industry and to individual farmers and bird owners.

15. What Happens in an Outbreak In the event of an outbreak of HPAI and END, federal and state officials are likely to use tools such as quarantine, flock depopulation, and control of product movement to prevent the spread of the virus.
Animal health officials may:
Quarantine the affected areas
Monitor the uninfected birds for clinical signs until the quarantine is lifted
Humanely depopulate the infected birds in order to prevent its further spread
Remove carcasses of the birds from the premises in a manner that prevents the spread of infection. Clean and disinfect the area as quickly and thoroughly as possible
Audio Script: In the event of an outbreak of HPAI or END, Federal and state animal health officials in the U.S. work together to prevent the disease from spreading. They may place quarantines on the premises of affected properties, and have birds monitored periodically for signs of disease until the quarantine can be lifted. If birds have been exposed to the disease, they may need to be humanely disposed of in order to prevent further spread.
To prevent END from being introduced into U.S. poultry flocks, APHIS requires that all imported birds including poultry, pet birds, birds exhibited at zoos and ratites be tested and quarantined before entering the country.

16. Identification of END and AI in Poultry
Diagnosis for these diseases is made at state, university or federal laboratories:
Clinical signs or testing of blood samples will provide evidence of the presence of a infection
A definitive diagnosis can be made on live birds by taking a tracheal, oropharyngeal or cloacal swab and identifying the virus
If birds are dead, the laboratory can sample respiratory or digestive system tissue or use tracheal, oropharyngeal, or cloacal swabs to identify the virus sample
Audio Script: END and AI can be diagnosed in both live birds and dead specimens. Most commonly, in live birds, swabs of the throat area and/or feces may be tested at state, university, or federal diagnostic laboratories using a rapid diagnostic technique or by virus isolation which can indicate the presence of the virus in a very short time. Blood tests, called serology, are less effective than virus isolation for testing END. For AI, blood or egg yolk may be tested for presence of antibodies that would indicate infection.

17. How to Safeguard Your Birds Against an Outbreak of END and AI Practicing biosecurity is a means of protection against AI and END.
Precautions: END is a threat to birds. All bird owners should take the following precautions to avoid an outbreak of this disease:
Ask bird suppliers for copies of paperwork that prove their birds are imported into the United States legally or are from U.S. stock, were healthy before being shipped, and were transported in new or thoroughly disinfected containers
Keep records of all sales, shipments, and movements of birds
Separate all newly purchased birds from older ones for at least 30 days. Examine the new birds, checking for any signs of disease or illness before introducing them into your flock
Remember to practice the six biosecurity steps
Audio Script: END and AI viruses spread rapidly because some birds are carriers of the disease without any known or visible signs of the virus. By making biosecurity a part of your daily routine, you can decrease the chances of your birds being infected by END and AI.
Don't wait. If your birds are sick or dying, call your local cooperative extension office, local veterinarian, your State veterinarian, or the USDA's Veterinary Services office to find out why. The USDA has a toll-free hotline
( ) with veterinarians to help you.

18. Summary END and HPAI are the most infectious poultry diseases in the world. These diseases attack most species of birds. The outbreak of END in California and other western states in 2002 cost them and the Federal government over $170 million. It also cost countless bird and poultry owners their pets, and in some cases, their livelihoods. Therefore, the best way to prevent these diseases is by practicing good biosecurity. In this lesson, you learned about the:
Causative agents of END and AI
Type of birds affected by END and AI
Global nature of END and AI and the economic impact on the U.S. poultry industry
Clinical signs of END and AI
Difference between high-pathogenicity and low-pathogenicity
Actions to take if the clinical signs of END and AI are recognized
Process used to identify END and AI in poultry
Prevention of the spread of END and AI
Audio Script: In this lesson, you learned to differentiate between high pathogenicity and low pathogenicity AI, besides also learning to spot the clinical signs of
END and AI and preventing their spread. You are the best protection your birds have. If you follow basic biosecurity measures and make them a habit, you will greatly decrease the risk of carrying disease to your birds.

19. How to Safeguard Your Birds Against an Outbreak of END and AI
Biosecurity is the only practical protection against an outbreak of AI or END.
Precautions:
All bird owners should therefore take the following precautions to avoid an outbreak of this disease:
Ask bird suppliers for copies of paperwork that proves their birds are imported into the United
States legally or are from U.S. stock, were healthy before being shipped, and were transported
in new or thoroughly disinfected containers
Keep records of all sales, shipments and movements of birds
Separate all newly purchased birds from older ones for at least 30 days. Examine the new
bird, check for any signs of disease or illness before introducing it into your flock
Audio Script: END and AI viruses spread rapidly because some birds are carriers of the disease without any known or visible symptoms of the virus. By making biosecurity a part of your daily routine, you can decrease the chances of your birds ever being infected by END and AI.
Call your veterinarian or local extension agent to examine all your sick birds or birds that die suddenly and without cause, especially if you have been with other people’s birds or brought home new birds.

20. Summary
END and HPAI are the most infectious poultry diseases in the world. These diseases attack most species of birds. The outbreak of END in California and other western states in 2002 cost them and the Federal government over $170 million. It also cost countless bird and poultry owners their pets, and in some cases, their livelihoods.
Therefore, the best way to prevent these diseases is by practicing good biosecurity.
In this lesson, you learned about the:
Causative agents of END and AI
Type of birds affected by END and AI
Global nature of END and AI and the economic impact on the U.S. poultry industry
Clinical signs of END and AI
Difference between high-pathogenicity and low-pathogenicity
Actions to take if the clinical signs of END and AI are recognized
Process used to identify END and AI in poultry
Prevention of the spread of END and AI
Audio Script: In this lesson, you learned to differentiate between high pathogenicity and low pathogenicity AI, besides also learning to spot the clinical signs of END and AI and preventing their spread.
You are the best protection your birds have. If you follow basic biosecurity measures and make them a habit, you will greatly decrease the risk of carrying disease to your birds.

21. Choose the correct answer
1. The following are Clinical signs of END:
Sudden death
Production of thick-shelled eggs
Drooping wings
Swollen tissues around the bird’s eye and neck
Mild conjunctivitis
Greenish, watery diarrhea
Complete paralysis
Correct Answer: Sudden death, Drooping wings, Swollen tissues around the bird’s eye and neck, Greenish, watery diarrhea, Complete paralysis