Exotic Newcastle Disease
Exotic Newcastle disease (END) is a contagious and fatal viral disease
affecting most species of birds. Exotic Newcastle is a foreign animal
disease in the U.S. and is considered the most infectious disease of
birds and poultry. END is so virulent that many birds die before showing
any clinical signs. A death rate of 100 percent can occur in unvaccinated
poultry flocks and jeopardize a state’s poultry production and
limits international trading opportunities.
Impact
An outbreak of END is extremely difficult and costly to eradicate.
In 1971, southern California experienced a major outbreak in commercial
poultry flocks. The disease threatened the California poultry industry,
which ranks first in the nation for egg production and fourth for
turkey production. Had the disease spread beyond the state’s borders,
the entire country’s egg and poultry supply would have been jeopardized. The
outbreak in California was finally eradicated in l974, but the toll
was high. In all 1,341 infected flocks were identified, and nearly
12 million birds were destroyed. Eradication efforts cost taxpayers
$56 million, and severely disrupted the operations of many producers. Consumers
paid the price, too, as prices of poultry and poultry products increased.
In October 2002, END was again diagnosed in California in non-commercial
flocks. As of early January 2003, the disease had spread to at least
three commercial poultry operations, and more than 600 veterinarians
and animal health inspectors were working to eradicate the outbreak. This
time however, the disease has spread to other states.
How does END spread?
The END virus is spread when the bodily discharges of infected birds
come in contact with healthy birds. Discharges, which contain high
concentrations of the virus, include droppings, or secretions from
the bird’s nose, mouth or eyes. In close confinement, such as
commercial operations, the disease can spread like wildfire.
The virus also can be picked up on shoes, clothing or equipment and
can be carried from an infected flock to a healthy one. That is why proper
biosecurity measures must be followed when owners, work crews, service
personnel, manure haulers, renderers or feed trucks come to a poultry
premise. END 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.
Smuggled pet birds, especially Amazon parrots from Latin America, pose
a great risk of introducing END into U.S. flocks. Amazon parrots that
are carriers of the disease but do not show symptoms are capable of shedding
the END virus for more than 400 days.
Clinical Signs
END affects the bird’s respiratory, nervous, and digestive systems.
The incubation period for the disease ranges from 2-15 days. Although
the following are classical signs of END, some birds may die so quickly,
they show no signs before death.
Signs can include:
• 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
• Partial to complete drop in egg production.
• Production of thin-shelled eggs
• Swelling of the tissues around the eyes neck
• Sudden death
• Increased death loss in a flock
How can poultry producers help control & prevent
END?
Eradicating END from poultry operations requires strict quarantines and
in-depth surveillance. All infected or exposed flocks must be
destroyed. Poultry producers should ensure the following biosecurity
measures are taken to prevent the introduction of the disease to commercial,
non-commercial, and hobby flocks.
• Allow only essential workers and vehicles on the premise.
• Don’t keep pet birds on the farm. Don’t hire employees
who own birds or poultry.
• Don’t allow vaccination crews, catching crews, and other service
personnel on the premise, if they have been in contact with
other poultry operations within the previous 24 hours.
• Clean and disinfect the tires and undercarriages of any vehicles
entering or leaving the premises.
• Provide clean clothing and disinfectant for employees’ boots
or shoes.
• Maintain an “all-in, all-out” philosophy of flock management
with a single age flock.
• Control the movement of poultry and products from farm to farm.
Do NOT add birds unless you know the health status of the source flock!
• Clean and disinfect poultry houses between each lot of birds.
• Control movement associated with the disposal and handling of bird
carcasses, litter, and manure.
• Avoid visiting other poultry operations.
• Protect flocks from wild birds that may try to nest in poultry houses
or feed with domesticated birds.
•Take diseased birds or dead birds to a diagnostic laboratory for
examination.
How can pet bird & backyard poultry owners help control & prevent
END?
Besides jeopardizing the commercial industry, END also poses a threat
to the caged-bird industry and poultry hobbyists. Birds smuggled into
the U.S. illegally bypass the quarantining and testing procedures of
the U.S. Department of Agriculture (USDA). If the birds are carrying
the virus, owners and animal health officials may not discover the infection
until an outbreak occurs. To protect the U.S. poultry and bird industry,
owners of pet birds should:
• Require suppliers to provide certification that birds were legally
imported, or are of U.S. stock. Insist that the suppliers ensure birds
are healthy prior to shipment, and that the birds will be transported in
new or thoroughly disinfected containers.
• Maintain records of all purchases,sales and shipments of birds.
• Isolate all newly purchased birds for at least 30 days. Restrict
the movement between new and old birds, and practice good biosecurity!
How should suspicious cases be reported?
Don’t wait! If you have unexpected death loss or illness among
your birds, report it to the Maine Department of Agriculture, Division
of Animal Health immediately. You can reach Don Hoenig, VMD, State
Veterinarian at 207-287-7615 or Chip Ridky, DVM, USDA Veterinarian for
Maine at 207-287-7632. For importation requirements visit our web site
www.maine.gov/agriculture/
