United States Department of Agriculture • Animal and Plant Health Inspection Service

ANIMAL DISEASE ALERT

APHIS 91–55–067 February 2003

Exotic Newcastle

Disease

Exotic Newcastle disease (END) is a contagious and

fatal viral disease affecting all species of birds. END

is so virulent that many birds die without having

developed any clinical signs. END can infect and

cause death even in vaccinated poultry. Mortality is

up to 90 percent of exposed birds. The U.S.

Department of Agriculture’s (USDA) Animal and Plant

Health Inspection Service (APHIS) is the Federal

agency that takes the lead in excluding END from the

United States and responding to any END outbreaks

that do occur.

Clinical Signs

END affects the respiratory, nervous, and

digestive systems. The incubation period for the

disease ranges from 2 to 15 days. An infected bird

may exhibit the following signs:

• Respiratory: sneezing, gasping for air, nasal

discharge, coughing

• Digestive: greenish, watery diarrhea

• Nervous: depression, muscular tremors,

drooping wings, twisting of head and neck,

circling, complete paralysis

• Reduction in or complete loss of egg production

• Swelling of the tissues around the eyes and in

the neck

• Sudden death

Introduction and Spread of END

END is spread primarily 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 can also be spread easily by mechanical

means. 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.

END can survive for several weeks in a warm

and humid environment on birds’ feathers, manure,

and other materials. It can survive for very long

periods in frozen material. However, the virus is

destroyed rapidly by dehydration and by the

ultraviolet rays in sunlight. Figure1–Chickens with END exhibit signs of depression and

respiratory distress.

Figure 3–Birds illegally smuggled into the United States are not

quarantined and tested by the USDA and therefore may carry the

exotic Newcastle virus.

Figure 2–Another symptom of

END is the inability to perch or

fly, as shown in this picture of

an affected parakeet.
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Biosecurity Measures on the Farm

The only way to eradicate END from commercial

poultry is by destroying all infected flocks and

imposing strict quarantine and in-depth surveillance

programs. Poultry producers should strengthen

biosecurity practices to prevent the introduction of

END into their flocks. Biosecurity is also important to

protect backyard and hobby flocks. The following are

tips on proper biosecurity practices:

• Permit only essential workers and vehicles on the

premises.

• Provide clean clothing and disinfection facilities

for employees.

• Clean and disinfect vehicles (including tires and

undercarriages) entering and leaving the

premises.

• Avoid visiting other poultry operations.

• Maintain an “all-in, all-out” philosophy of flock

management with a single-age flock.

• Protect flocks from wild birds that may try to nest

in poultry houses or feed with domesticated birds.

• Control movements associated with the disposal

and handling of bird carcasses, litter, and

manure.

• Take diseased birds to a diagnostic laboratory for

examination.

Biosecurity Measures for BackyardPoultry Enthusiasts and Pet-Bird Owners

END is also a threat to the caged-bird industry

and poultry hobbyists. Birds illegally smuggled into

the United States are not quarantined and tested by

USDA and therefore may carry the END virus.

Owners of pet birds should

• Request certification from suppliers that birds are

legally imported or are of U.S. stock, are healthy

prior to shipment, and will be transported in new

or thoroughly disinfected containers.

• Maintain records of all sales and shipments of

flocks.

• Isolate all newly purchased birds for at least 30

days.

• Implement stringent biosecurity practices to

prevent the introduction of END to pets and

backyard flocks.

What Happens in an Outbreak

In the event of an END outbreak, if you live on or

near an affected premises, you may see individuals

dressed in white suits, plastic boots, eye goggles,

masks, and other special clothing before they enter

your yard. These are Federal or State animal health

officials trained in disease control techniques. Animal

health officials take great precautions not to spread

END from one premises to another.

Animal health officials who have not been in

affected yards will canvas the area and place

quarantines on the premises of neighbors who own

birds. If they have not had exposure to infected birds,

these birds will be monitored periodically for signs of

disease until the quarantine can be lifted. If they

have been exposed to the disease, they may need to

be humanely depopulated in order to prevent further

spread.

Once a premises is identified as END positive,

Federal and State personnel will humanely

depopulate infected and exposed birds. The

carcasses of the birds will be removed from the

premises in a manner that prevents the spread of

infection. Cleaning and disinfection of the area will

then be conducted as quickly and thoroughly as

possible.

In addition, to prevent END from being introduced

into U.S. poultry flocks, APHIS requires that all

imported birds (poultry, pet birds, birds exhibited at

zoos, and ratites) be tested and quarantined for

diseases before entering the country.

Figure 4–If END is detected in U.S. poultry, measures such as

quarantine, control, and cleanup are implemented to prevent

opportunities for the virus to spread.

Report Suspicious Signs

If birds exhibit clinical signs of END or may have

been exposed to birds with the disease, immediately

notify Federal or State animal health officials.

Additional Information

For additional information on END and on how to

contact Federal or State animal health officials, visit

the APHIS Web site at http://www.aphis.usda.gov/lpa/

issues/enc/exoticnc.html.