University of California
to Prevent the Spread of Exotic Newcastle Disease
California, Davis CA 95616
Douglas R. Kuney
Extension Poultry Farm Advisor
Highlander Hall-C Rm 142, Riverside, CA 92521
Sources and Transmission
Sources of virus. Exotic Newcastle disease virus (NDV) can infect a wide variety of
bird species. Some species do not show
any or only limited signs of disease if they become infected. Parrots and other psittacine birds are
especially dangerous because they can carry exotic Newcastle disease virus and
show no clinical signs. Many other
birds can become infected with NDV but have not been associated with the transmission
of disease to chickens and turkeys.
Despite the wide number of species that can be infected by Newcastle
disease virus, chickens and turkeys are most likely to be infected by infected
chickens and turkeys. Most infected
chickens and turkeys eventually die from this disease but there is a period
before they succumb when they can easily spread the virus.
Newcastle disease virus is hardy and can easily survive on the feet, hands, and
clothes of humans. In addition, it can
survive in the eyes and in nasal passages of people who have been in contact
with infected birds.
Transmission between premises. The virus is excreted in feces and
from the respiratory tract as an aerosol.
The virus can easily contaminate feed, water, footwear, clothing, tools,
equipment, and the environment. Fertile
eggs laid by infected hens can carry virus although they rarely hatch. However, the distribution of hatching eggs
from an infected flock can carry the virus to susceptible birds.
A. Isolation refers to the confinement of animals within a
controlled environment. A fence keeps
your birds in, but it also keeps other animals out.
- Prevent the introduction of new birds to a
previously infected facility for 2-3 weeks after a complete cleanout. All birds should be removed in this
- Clean out vegetation around poultry houses and
pens to remove shelter and food for possible carriers of the virus.
- Institute a vector control program for insect,
mammalian, and avian vectors.
These vectors are important because they can both directly transmit
or indirectly carry infected feces from one house, pen, or premise to
- If possible, keep birds in closed houses or
coops rather than exposed to wild birds.
- Institute an insect control program.
- Rodent control and preventing their traffic
between houses on a single premise are essential.
- Prevent the accumulation of standing water. This is a great attraction to migrating
waterfowl, which can carry NDV without showing clinical signs of
- Limit sources of food for wild and free-flying
birds. Cover all feed
storage. NDV has been transmitted
to naïve birds via contamination of feed with infected feces. Clean up
spills when they happen.
- Educate your employees about the potential
dangers of live bird markets, pet stores, fairs and other poultry and
advise them not to raise their own poultry for any purpose. Advise them not to visit any place with
birds when they will also have contact with your flocks.
- Advise your employees to avoid dead wild and
free-flying birds they find. Any
found on your premises must be treated as though they are highly
infectious. Handle them with
gloves, place in a plastic bag, and seal it, finally, a complete change of
clothes including shoes and a shower should happen before entering poultry
B. Traffic control includes
both the traffic onto your farm and the traffic patterns within the farm.
- Be a good neighbor. If you have or suspect Exotic Newcastle disease, initiate a
- Most critically, stop all movements of people
- Get birds (some sick and some dead) to the
diagnostic laboratory (phone numbers follow)
- Get advice (contacts follow)
- Keep logbooks of visitors to your facilities.
- Keep human farm-to-farm traffic to a
minimum. Conduct business by phone
- Find out where someone has been before inviting
them onto your premises. Inspect
visitors for evidence of cleanliness and contact with other birds before
they come onto your premises.
- Make no unnecessary visits to other farms.
- Do not let truck drivers, repairmen, or delivery
personnel step out onto your facility without clean or new protective foot
covering and clean coveralls. It
is best to provide plastic boots and coveralls for this purpose. Shoes and clothes are an excellent
vehicle for the transmission of NDV.
- If your company has several farms, establish
zones to prevent one person from traveling to all farms.
- Require employees and crews to wear freshly
laundered clothing or clothing supplied at the farm each day. Do not allow persons employed at other
poultry operations on your premises.
- Isolate dead bird disposal outside the perimeter
of the ranch. Control traffic to
and from bird disposal. Carcasses
can be a significant source of NDV.
Any unusual mortality should be taken to the laboratory for a
diagnosis as soon as it is possible (Laboratory phone numbers
C. Sanitation addresses the disinfection of materials, people, and
equipment entering the farm and the cleanliness of the personnel on the farm.
- Newcastle disease virus is a hardy virus and can
survive at room temperature for days to months. However, NDV is sensitive to most disinfectants and can be
readily inactivated if a surface is properly cleaned first. A list of disinfectants effective in
killing NDV follow.
- Organic material, like feathers and feces, must
be removed before disinfection by any method can be effective. Cleaning protocols should include a
fair amount of elbow grease and critical inspection.
the spread of NDV on equipment
- Make sure that any vehicles coming near your
flocks are not contaminated with litter or feces. Wash and disinfect the tires and wheel
wells of all vehicles coming onto your premises.
- Wash with detergent and disinfect bird hauling
equipment and vehicles.
- Wash and disinfect manure clean-out equipment
taken from farm to farm.
- Enclose all dead birds to be taken to the
laboratory in plastic bags.
Confine live birds being submitted to the laboratory in boxes that
will not return to your farm.
Disinfect any vehicles returning from the laboratory including the
floor mats. Do not let anyone who
has been to the laboratory return to your flock without a shower and a
change of clothes.
- Do not allow vehicles in areas grossly contaminated
- Wash and disinfect all egg trays, carts, and
racks making sure to remove all feathers, feces, and egg material.
specifics of cleaning and disinfecting any facility will depend on a large
number of factors that differ between farms.
Hence, it is not possible to address each individual concern. However, these are some guidelines that
generally address cleaning and disinfection and some facts that should be
considered when developing a strategy for cleaning and disinfection following a
flock push-out. In all situations, it
is highly recommended that a professional advisor be consulted to help develop
and implement any plans.
- Spraying a facility with a viricide after
complete depopulation is the best method to remove NDV from an infected
facility. At the same time a
vector control program should be instituted, followed by removal of
manure, cleaning of all surfaces followed by a second application of
viricidal spray. All manure should
be removed and all surfaces thoroughly dry cleaned prior to applying
disinfectants. Next, apply the
disinfectant to all surfaces twice, allowing the disinfectant to dry
between applications. The house
should be left empty for 2-3 weeks before repopulation.
- Although most birds are vaccinated for Newcastle
disease, vaccines cannot protect flocks from exotic Newcastle
disease. This virus, if it gets
into a flock of vaccinated chickens or turkeys, their mortality may still
be nearly 100%.
The Newcastle disease virus is extremely sensitive to many
disinfectants. However, it is very
difficult to inactivate the virus if it is in organic material, such as
feces. Therefore, it is very important
to use a combination of both cleaning and disinfection to get rid of this
Phenols such as One-Stroke EnvironTM
Hypochlorite such as bleach
Quaternary Ammonia disinfectants such as Roccal DTM
Peroxygens such as Virkon STM
*for information on disinfectants
and their proper use see http://www.vetmed.ucdavis.edu/vetext/INF-PO_Sanitation.html
1 This is
not a complete listing of effective or approved disinfectants and should in no
way be considered a recommendation. The
University of California does not in any way endorse this or any other commercial
of equipment to use in this and other biosecurity programs
- Portable high-pressure sprayers can be purchased
from hardware stores at a cost of $100-$500. These sprayers are useful in washing and disinfecting
equipment and poultry houses.
- Hand-held sprayers can be purchased from
hardware stores for $30-70. These
items are helpful for spraying disinfectants on the floor mats of cars,
disinfecting wheel wells, etc. In
addition, the same type of sprayer can be used to distribute insecticides
in a vector control program.
However, these sprayers do not have enough pressure to cut through
organic material and, thus, can only be used on clean equipment.
- Disposable coveralls, boots, and caps can be
purchased from several places. If
you need help finding them, feel free to contact the people listed at the
end of this document. Costs: Tyvek disposable coveralls are
$2.50-$3.50 each, plastic boots are $10-$13/10 pairs, and bouffant caps
are $14/case of 500. These items are useful to provide for visitors.
- Other materials important in a biosecurity
program including signs, gates, pylons, and other indications of barriers
can be purchased for minimal cost.
These items are important in preventing unwanted human traffic and
are well worth their cost.
Laboratories in California
California Animal Health and Food
San Diego County Laboratory—(858)
Dr. Francine Bradley, poultry
specialist (530) 752-6316
Dr. Ralph Ernst, poultry specialist (530)
Dr. Carol Cardona, poultry extension
veterinarian (530) 754-5041
Doug Kuney, poultry farm advisor (909)
California Department of Food
District office (909) 947-4462
District office (209) 491-9350