Transcript GOOD PRACTICES FOR BIOSECURITY IN THE PIG SECTOR WB/OIE/FAO guidelines

GOOD PRACTICES FOR
BIOSECURITY IN THE PIG
SECTOR
WB/OIE/FAO guidelines
Executive Summary
• zoonotic viruses prompting considerable
international concern
• Nipah Virus, Avian influenza, and now
pandemic H1N1
• There is impact on public safety, and
commercial trade of livestock
• Prevention of the spread of disease something
we can implement
Biosecurity
• “Biosecurity is the implementation of
measures that reduce the risk of the
introduction and spread of disease agents; it
requires the adoption of a set of attitudes and
behaviors by people to reduce risk in all
activities involving domestic, captive/exotic
and wild animals and their products”
General Principles specific to
pandemic H1N1
1. Visitors who are allowed to have contact with
swine should be limited to only people having
essential business on the farm; other
meetings should be conducted off farm if
possible
– Doors should be locked
– Signs should indicate visitors should not enter
facilities
General Principles specific to
pandemic H1N1
2. People clinically ill with influenza symptoms
should not enter barns and contact pigs until
they stop shedding the virus.
–
The Center for Disease Control (CDC) suggests
that the virus is shed up to 7 days from the onset
of symptoms, and children may shed longer.
General Principles specific to
pandemic H1N1
3. Swine workers and others with close contact
with swine, should be considered for
preventive measures such as protective
clothing (e.g. mask), medications and
influenza vaccination when available.
General Principles specific to
pandemic H1N1
4. Encouragement of regular hand washing be
implemented for farm workers and visitors.
– Hand washing opportunities should available and be
practical; they are suggested not only for influenza,
but for all diseases that can spread between pigs
and people
General Principles specific to
pandemic H1N1
5. Vaccination of swine for classical H1N1
influenza is safe, but efficacy against the
pandemic strain is not known.
–
–
If it can be proven to reduce clinical signs and
shedding, vaccination of herds for swine influenza
may be of value;
however, it may complicate surveillance for herds
wishing to stay serologically negative. The decision
to vaccinate swine herds should be carefully
discussed with the herd veterinarian before
implementing it.
The routes of Disease transmission
• Pigs
– Most frequently diseases move with infected pigs
– Do not move sick pigs
but
– Pigs incubating the disease may not be clinically ill
yet
– Recovered pigs may appear healthy but can
spread disease
Action points
• Inspect pigs before moving
• Use test to detect disease
– Antibody tests for previous exposure
• elisa
– Antigen for incubating disease
• PCR
• Quarantine incoming pigs
The routes of disease transmission
• Semen
– Boar semen can be a source of pathogens,
especially viruses. Several of the major pathogens
(CSFv, PRRSv, ADv…)
– Swine influenza virus replicates only the
respiratory tract, it is not shed into semen, and
accidental contamination of semen is thought not
result in transmission through artificial
insemination
The routes of Disease transmission
People
• It is clear that humans can transport the
pathogens on boots, clothes, and hands.
– Entry decontamination protocols
– Hand wash (shower) change of clothes
• Farm workers must not own pigs at home
• Thieves are a problem, not just because they
steal pigs or equipment, but also because they
may not stop to read the biosecurity protocols
first
The routes of pathogen transmission
feed including swill feeding, drinking water and bedding material
• Feed, bedding and water can all contribute to pathogen dissemination.
– seldom involved in a large-scale spread of epidemic diseases,
• Unpasteurized milk and milk by-products obtained from infected cattle
(e.g. Tuberculosis, Brucellosis) can be a source of pathogens.
• Fresh pork is a documented risk factor of transmission for a number of
pathogens, including Foot-and-Mouth-Disease virus, Classical Swine
Fever virus, African swine fever virus, PRRS and other systemic viruses.
– the use of kitchen/restaurant swill feed and diverse by-products
which can be obtained from slaughterhouses carries great disease
risk.
• Influenza virus does not become viremic and thus is not spread
through pork. It does not survive long outside the host; so feed, water
and bedding, are not thought to be a major source of transmission
The routes of pathogen transmission
Aerosol
• Pathogens can be transmitted by air, sometimes surprisingly long
distances.
• The efficacy of airborne transmission strongly depends on
geographical and climatic conditions.
•
It also depends on virus load being emitted from the source herd,
which is proportional its size and numbers animals present.
• The resistance of the pathogen to drying and sunlight determines
its ability to spread through the air
• No evidence that pandemic H1N1 spreads by aerosol from herd to
herd
The routes of pathogen transmission
Fomites (mechanical transmission)
• Vehicles, especially those used for
transporting pigs, are also efficient vectors of
pathogens and need due care.
• Birds, insects, rodents and other pest are
known to transport pathogens
• Pandemic H1N1 doesn’t survive long in
environment
• Role of wild birds in transmission is unknown
The importance of communication
strategies
• In order to make meaningful change in rural communities,
a well-designed communication plan is essential.
• The key to changing behaviors/practices lies in the level of
perception of risk.
• Communication strategies need to build on the way people
perceive their own situation
• Communication cannot be merely prescriptive it must
outline risk and benefit
The importance of communication
strategies
• Public and private sector should work together to
design and implement control and eradication
programs. Mutual trust between public and
private sector is essential.
• In cases where the disease has a zoonotic
concern, pre-emptive discussions between public
health agencies, agricultural departments and the
pig industry should take place to ensure mutual
understanding and cooperation in a public health
emergency.