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Control Strategies for Highly Pathogenic
Avian Influenza (H5N1) in Asia Incident Action Plan
The overall goal for response to a Highly Pathogenic Avian
Influenza is to detect, control, and eradicate the agent as
quickly as possible to return individual farms to normal
production and the Country to disease free status. The
response target time to accomplish this goal should be four
months or less, as response efforts become more difficult to
maintain after such a period of time. Avian influenza may
impact the abundance, availability, cost, or safety of the
Country's food supply, and the ability to market agricultural
products. Control and elimination of avian influenza relies on
three basic principles which make up the operational
components of a response:
• Preventing contact between susceptible animals and HPAI
agents is accomplished by the following actions: quarantine
and movement controls, biosecurity measures, and epidemiologic
investigations with risk assessments, tracing, and
surveillance.
• Stopping the production of the agent by the infected
animals. This is accomplished using euthanasia and disposal of
infected and exposed animals.
• Increasing the disease resistance of susceptible animals.
This is accomplished by strategic vaccination.
To accomplish the control of HPAI the following is a summary
of the specific recommendations were discussed by the
participating countries:
Organizational Approach to the Delivery of Control
Strategies
Throughout the course of the presentations by both infected
and non infected Countries the need for cooperation across
country boundaries was a common theme. For any country's
program, be it to eradicate the disease or remain free depends
upon their neighbour's success. For this reason it is
imperative that the following be implemented immediately:
• A regional coordination group should be formed by FAO, OIE,
WHO and the Central Governments of the Countries in the region
to allow joint decision making, resource and information
sharing. This group should establish goals and objectives of
the regional plan in sufficient detail to guide planning and
operations.
• Establish a Veterinary Task Force in charge of preparing
emergency control, contingency, and response plans should
include, among others from other Agencies, individuals
responsible for the public health sector for consultation by
these authorities.
• Each Country will need to assess and further develop
adequate capacity within their veterinary infrastructure
(human resources, equipment and laboratory supplies to name a
few) to accomplish the recommendations contained in this
report.
• The development of emergency preparedness programs should be
completed to prevent the establishment of infection or
reinfection.
• A zoning approach to expand free areas while driving the
disease into smaller and smaller pockets is essential to
control within the region.
• A regional laboratory network system needs to be established
as the closest laboratory may be in a neighboring country.
This would also allow reagent production and sharing as
needed.
• Development of common educational materials for biosecurity
and public health should be completed and shared with the
region for translation and distribution across the region
would be essential for biosecurity and containment.
Notification
• International reporting standards of the OIE is
essential to establish confidence on the world stage of
veterinary actions and progress toward stated goals.
• Additionally, the development and use a common daily
situation reporting format that can be used for internal
planning purposes is critical to continual evaluations of the
program. This reporting format should be simple but sufficient
to demonstrate progress toward goals.
Country Zoning/compartmentalization, Quarantine, Movement
Controls and Surveillance
The primary means of spread is by movement of infected birds,
materials or means of transport. While each country has
applied quarantine and movement controls in known infected
areas adequate surveillance may not have been conducted in
what is thought to be "free" areas. Participants also
discussed the need for a coordinated regional approach to
eradication.
• Poultry populations should be divided into 3 categories
(industrial commercial poultry, small commercial production
and village poultry (subsistence farming and pet birds).
• Countries should move to a system of zones based on
populations of poultry, geographic areas or disease status
with the aim of developing free zones and recovery of export
capacity.
Epidemiology
Given the unprecedented nature of the current disease
outbreak it is inadequate on a global scale to allow a country
by country epidemiologic report. A regional epidemiologic
study must be conducted to assist in decision making and
planning for the region.
• Resources should be made available to conduct an
epidemiologic assessment by international and local experts to
develop a descriptive epidemiologic analysis of the outbreak.
• A molecular analysis of isolates should be conducted with
the assistance of the OIE/FAO/WHO reference laboratories to
complement the epidemiological analysis.
• Support for research on disease transmission among other
things to help control the disease in the region.
Strategic Vaccination
A discussion of the use or non use of vaccine followed a
presentation on the advantages and disadvantages of vaccines
for avian influenza. The generally acceptable summary of that
discussion is that:
• Vaccine is a valuable tool in the control and elimination of
avian influenza
• Vaccine alone is unlikely to lead to a successful
eradication; however vaccination combined with stamping out
and adequate surveillance will likely lead to eradication in
less time.
• Strategic vaccination in birds, if accompanied by
appropriate surveillance will reduce the amount of virus
excreted and lead to less viral exposure for humans
• Vaccine, if used, must be produced in accordance with OIE
guidelines.
Stamping-out policy for infected poultry (including
Valuation, Disposal, Cleaning and Disinfection, Biosecurity
and Animal Welfare)
• Infected and susceptible animals will be euthanized and
disposed of as soon as possible but striving for the
recommended time of within 24 hours.
• Susceptible animals and on all suspect premises will be
subject to regular inspection and observation over two or more
incubation periods of the disease.
• If resources are limited, premises will be prioritized so
that those with high potential for active spread of the agent
are acted on before those that do not have a high potential
for active spread.
• Depopulation should be accompanied with adequate and timely
compensation payment to owners of animals and materials
requiring destruction to prevent the spread of avian
influenza.
• A study should be conducted looking at alternatives to
compensation and analyzing the hazards, risks and alternative
schemes for compensation should be conducted.
• Provide humane euthanasia methods for all animals to be
euthanized.
• Contaminated and potentially contaminated materials,
including animal carcasses, will be properly disposed of
within 24 hours of the destruction of the susceptible animals.
Disposal will be done in a manner that does not allow the
avian influenza agent to spread, has little to no effect on
the environment, and conserves meat or animal protein if
logistically supportable from a biosecurity viewpoint.
• All premises on which animals are euthanized and disposed of
will be required to be cleaned and disinfected.
• Biosecurity procedures to prevent the spread of avian
influenza will be implemented within 24 hours of the
identification of the first presumptive positive premises
Wildlife Management
Massive killing of wild birds thought to be pests in the
region lead to massive famine and failed crops since the wild
birds in fact were controlling crop pests more than being crop
pests. Therefore wildlife not only warrant protection due to
the aesthetic and cultural values, but also because of the
ecosystem "services" provided at very low costs by animals and
plants in the environment. As a result:
• Wild birds should not be depopulated in an attempt to
control avian influenza but separation, as much as possible
should be attempted.
• Reducing contact rates between wild birds and large
commercial poultry operations to prevent wild waterfowl from
direct or indirect contact.
• Village poultry health care programs, including possible
vaccination programs and certainly health/husbandry education
is the best approach to 1) provide entree for surveillance
operations, 2) reduce disease incidence, 3) improve rural
livelihoods, and 4) reduce the threat or introduction of
diseases into wild bird populations.
• Ministries of Agriculture, as well as Ministries of Natural
Resources should limit the trafficking of wild birds, and ban
the mixing of domestic and wild animals in live markets.
• Wildlife infectious disease surveillance programs, both in
semi-urban areas and in remote, rural areas may provide
insights and early warning about diseases circulating in the
wild prior to livestock outbreaks.
• Investment in raising awareness and capacity building is
needed to allow more countries to begin integrating health
monitoring programs as they develop natural resource
management efforts.
Rehabilitation
• Plans to rebuild the poultry sector must be developed and
implemented to set the poultry industry in a more biosecure
position and protect livelihoods.
• Establishment of educational programs for improved poultry
production should be started.
FAO
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