Control Measures for Avian Flu
Once Avian Flu has been detected in live or dead birds, it must
be reported to the authorities. From there, authorities
will go about containing the spread of the disease. The
first key to containing the disease or disease outbreak is the
culling (killing) of sick and exposed birds. Culling will
prevent the spread of the avian flu to other birds (and farms),
and also minimise the risk of human infection.
When a territory, usually the area where the virus has been detected,
has been identified, the authorities will notify all poultry farms,
wholesalers, and retailers in the territory of the culling event.
These businesses will usually be compensated. The territory
will be placed under quarantine to restrict movement of live poultry
out of the area.
Culling of poultry will be more extensive at the source where
the Flu virus was detected, or source of outbreak. Culling
is performed as humanely as possible, under rigid animal welfare
guidelines. Farms, wholesale markets, and retail outlets
will be depopulated in an appropriate manner.
There are no treatment measures for infected birds. It
appears that it is more important to prevent further spread of
the virus rather than saving the bird. Understandably with
humans, it is a different story.
Treatment of Avian Flu in Humans
Anti-viral drugs are given to humans who may be infected with
Avian Flu. These drugs are also used to combat human influenza.
In the United States, four antiviral medications are approved
for treatment of influenza. These are:
- Zanamivir (limited supply)
When used for treatment within the first two days of illness,
all four antiviral medications are similarly effective in reducing
the duration of illness by one or two days. People who are
at high risk of serious complications from Avian flu are given
top priority to these medications. Three of these antiviral
medications (amantadine, rimantadine, and oseltamivir) are also
approved for prophylaxis (prevention) of influenza.
The Centre of Disease Control recommends that any person experiencing
a potentially life-threatening influenza-related illness should
be treated with antiviral medications. Also, any person
at high risk for serious complications of influenza and who is
within the first 2 days of illness onset should be treated with
antiviral medications. In children, rimantadine is approved
for prophylaxis among children aged >1 year and for treatment
and prophylaxis of influenza among adults. Although rimantadine
is approved only for prophylaxis of influenza among children,
certain specialists in the management of influenza consider it
appropriate for treatment of influenza among children. Also
available for treatment of children (>1 year) are amantadine
and oseltamivir, or zanamivir for children aged over 7 years.
Prevention of Avian Flu
The main key to control the avian flu is through prevention.
Like they say, "an ounce of prevention is worth a
pound of cure".
Drastic measures are made to prevent the spread of avian flu.
Mass culling of poultry infected, or potentially exposed to the
virus is performed to minimise the spread of the virus over areas.
Once an outbreak is controlled, authorities strongly advocate
preventative measures to ensure that avian flu does not arise
again. In fact, some embargo's may be placed on countries
that do not follow these preventative measures.
Basic bio-security procedures can slow down the spread of the
virus and minimise the contamination of poultry with the virus.
Strict on-farm and personal bio-security practices protect poultry
operations of any size. Authorities suggest the following
practices to minimise Avian Flu infection and transmission:
- Keep poultry in closed poultry houses to
prevent contamination of wide areas. This has been problematic
in the Avian flu outbreaks in Southeast Asia where many affected
farms allowed their poultry to range freely.
- Keep wild birds and their faeces away from poultry and poultry
feed. Wild birds, particularly migratory waterfowl, have
been implicated as carriers or reservoirs of the virus.
They are more resistant to the disease, thus they can go harbouring
and shedding the virus for long periods of time. Many
of the avian flu outbreaks suggest that the point source of
infection originated from wild birds passing on the virus to
- Seal poultry house attics and cover ventilation openings with
- Thoroughly and routinely clean all equipment, vehicles, including
service vehicles, clothing and footwear before and after coming
into contact with poultry. Birds shed large amounts of
virus through their faeces and nasal passage (nasal spray, saliva).
- Ensure proper hygiene practices for all persons coming into
contact with poultry.
- Maintain high sanitation standards in and around poultry houses
- Isolate or avoid introducing new birds into existing poultry
flocks if their health status is unknown.
- Limit access to poultry houses, including farm workers, feed
suppliers, poultry veterinarians, catching crews, sawdust and
shavings suppliers, agricultural service personnel and casual
- Avoid using water in poultry houses contaminated with faeces
from wild birds.
- Ensure thorough cleaning and disinfecting for all cages transporting
- Maintain a log of all visitors coming into contact with poultry.
Avian Flu Vaccinations
In an effort to control widespread infection among poultry, experts
from the UN's Food and Agriculture Organisation (FAO), the World
Organisation for Animal Health (OIE), and the World Health Organisation
held meetings in February 2004. The group endorsed the wider
use of vaccination in an effort to diminish the impact of avian
flu in the future. However, while vaccination may be a viable
option for curbing the spread of influenza in animals, to date
there is no H5N1 avian flu vaccine that is licensed by the European
Union or the United States for use in humans.
Poultry vaccination is already in use and encouraged in countries
such as China and Indonesia, but other countries have challenged
vaccination as a control measure. Some studies have shown
that some OIE-approved vaccines take some time to confer immunity
to vaccinated birds and may not fully prevent birds from becoming
infected or excreting virus. This has caused considerable
controversy over the benefits and risks of vaccination.
Opponents of vaccinations feel that humans can be more at risk
being exposed to vaccinated birds that may be healthy-looking
and show no symptoms of disease, but may harbour the virus anyway,
particularly the lethal H5N1 subtype. As a result, besides
banning all poultry products reporting H5N1 infections, the European
Union has implemented a three-year ban on imports from any country
where chickens have been vaccinated against avian influenza.
Citing concerns about possible human transmission of H5N1 during
vaccination, Thailand, which exports 30% of its poultry to the
EU, has refused to vaccinate its flocks and has gone so far as
to ban the use of vaccine in the country