• Animal Health
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• Animal Disease Information
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• Avian Health
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• Biosecurity for Birds

Know the Signs of Disease and How to Report Suspected Illness

What Is Avian Influenza (AI)?
AI viruses can infect chickens, turkeys, pheasants, quail, ducks, geese and guinea fowl, as well as a wide variety of other birds. Migratory waterfowl have proved to be a natural reservoir for the less infectious strains of the disease known as low pathogenicity avian influenza. AI viruses can be classified into low pathogenicity (LPAI) and high pathogenicity (HPAI) based on the severity of the illness they cause. HPAI is an extremely infectious and fatal form of the disease that, once established, can spread rapidly from flock to flock. However, some LPAI virus strains are capable of mutating under field conditions into HPAI viruses.

Signs of Avian Influenza

• 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, sneezing
• Lack of coordination
• Diarrhea

How Is AI Spread?
The disease can be spread to birds from contact with infected wild birds and their droppings, or from bird to bird by direct contact. AI viruses can also be spread by manure, equipment, vehicles, egg flats, crates, and people whose clothing or shoes have come in contact with the virus. AI viruses can remain viable at moderate temperatures for long periods in the environment and can survive indefinitely in frozen material.

For more information, visit APHIS’ avian influenza page. 

What is Exotic Newcastle Disease (END)?
END, also known as virulent Newcastle Disease (vND), is a contagious and fatal viral disease affecting all species of birds. END is one of the most infectious diseases of poultry in the world and is so deadly that many birds die without showing any signs of disease. A death rate of almost 100 percent can occur in unvaccinated poultry flocks. It can infect and cause death even in vaccinated birds.

What Are the Signs?
END is a deadly viral disease that can affect all species of birds. END spreads quickly and can infect and cause death even in vaccinated poultry. An infected bird may show the following signs:

• Sudden death and increased death loss in flock
• Sneezing, gasping for air, nasal discharge, coughing
• Greenish, watery diarrhea
• Decreased activity, tremors, drooping wings, twisting of head and neck, circling, complete stiffness
• Swelling around the eyes and neck

How Does END Spread?
END is spread mainly through direct contact between healthy birds and the bodily discharges of infected birds. The disease is transmitted through infected birds' droppings and secretions from the nose, mouth, and eyes. END spreads rapidly among birds kept in confinement, such as commercially raised chickens.

Virus-bearing material can be picked up on shoes and clothing and carried from an infected flock to a healthy one. The disease is often spread by vaccination and debeaking crews, manure haulers, rendering truck drivers, feed delivery personnel, poultry buyers, egg service people, and poultry farm owners and employees.

The END virus can survive for several weeks in a warm and humid environment on birds' feathers, manure, and other materials. It can survive indefinitely in frozen material. However, the virus is destroyed rapidly by dehydration and by the ultraviolet rays in sunlight.