What is it?
Avian
influenza, or ‘bird flu’, is an infectious disease of animals caused by Type A
strains of the influenza virus. The virus normally infects only birds and, land
ess commonly, pigs. It sparked worldwide concern when the deadly H5N1 strain of
virus crossed the species barrier and claimed human victims in isolated, but
nonetheless headline grabbing cases. Although infected wild migratory water fowl
are thought to be primarily responsible for spreading the virus from location to
location, but experts recognize there are many other potential routes to global
pandemic, such as international travelers, or outbreaks not recognized and
contained quickly enough.
Short
history
Outbreaks
of the highly pathogenic avian influenza H5N1 strain of virus was found among
poultry flocks in eight Asian countries (Cambodia, China, Indonesia, Japan,
Laos, South Korea, Thailand, and Vietnam) during the period of late 2003 and
early 2004. At that time, it is estimated that more than 100 million birds in
the affected regions either died from the disease or were killed in order to try
to contain the outbreaks. By March 2004, the outbreak was reported to be under
control.
Since
late June 2004, however, new outbreaks of H5N1 influenza among poultry have been
reported in several countries in Asia and Eastern Europe (Cambodia, China,
Indonesia, Kazakhstan, Malaysia, Mongolia, Russia, Siberia, Tibet, Thailand,
Turkey, Romania, Ukraine and Vietnam). It is believed that these outbreaks are
ongoing. Additionally, outbreaks of influenza H5N1 have been reported among wild
migratory birds in China, Croatia, Mongolia, and Romania.
Human
cases of influenza A (H5N1) infection have been reported in Cambodia, China,
Indonesia, Thailand, Vietnam and most recently, Turkey.
Its
impact on human health …
Avian
influenza does not usually infect humans, but human outbreaks and some deaths
have been reported in a small number of countries in Asia, and additionally now
in Europe. According to the World Health Organization (WHO), approximately 150
human cases have been reported since 2003, with just over 50% of them proving
fatal. To date, all human infections have been linked to people working in or
living near poultry, such as farms and animal markets.
Experts
believe that human infections can occur because the H5 strain under some
circumstances is able to jump the species barrier. As of now, only a few human
cases of bird flu have been reported and this suggests that the virus is not
easily transmitted from birds to humans. Nevertheless, international health
authorities are spearheading preventive measures to contain the spread of
infection and minimize the possibility of the virus strains mutating to a form
which could be both highly infectious to humans and highly pathogenic
(illness-causing). This could happen for example, if a person was infected with
both human and avian influenza viruses at the same time.
Containment…
Control
measures recommended to contain the spread of the virus include:
-
Raising awareness amongst
those handling or rearing poultry and encouraging early detection and
notification.
-
Rapid destruction
(‘culling’ or ‘stamping out’) of all infected or exposed birds, proper
disposal of carcasses, and the quarantining and rigorous disinfection of
farms.
-
Seasonal influenza
vaccines for poultry workers.
-
Restrictions on movement
of live poultry, both within and between countries.
-
International financial
support to fund control measures required.
-
Creation of
country-specific guidelines and regional coordination programmes.
What about
Eating Poultry and Eggs?
International agencies such as the WHO and the Food and Agriculture Organisation
(FAO) state that it is safe to eat fully cooked poultry and eggs, as high
temperatures in cooking destroy the avian influenza virus. Similarly highly
processed chicken and egg products are also safe to consume, according to
manufacturers recommendations, because the high temperatures used in processing
will destroy the virus and other micro-organisms.
New research
confirms that industrial pasteurization processes of egg products is sufficient
to inactivate the heat sensitive Avian Influenza virus. The research shows that
using temperatures and times of heat application similar to those used in
commercial pasteurization of liquid egg products are sufficient in deactivating
the H5N1 strain of virus.
Here
are some simple food safety tips to help ensure that the poultry and eggs that
reach the table are both free of the avian flu virus and other micro-organisms
such as salmonella and campylobacter which can cause other illnesses.
When buying
poultry or eggs:
-
Purchase
only poultry and poultry products from shops with evident high food hygiene
standards or look for those retailers or caterers with national authority
certification of good hygiene practices
-
Avoid
buying live poultry, as bird flu can spread through close contact with
infected live poultry.
-
Select
fresh poultry meat and other products that have no signs of damage or
infection, such as unusually dark color, hemorrhage etc.
-
Select
fresh eggs, without feces staining on the shell. Avoid buying eggs with
cracked shells.
-
Canned
poultry products and chicken essence can be safely consumed, as all processed
foods undergo a heat treatment process that effectively destroys viruses.
When storing
/ thawing poultry and eggs:
-
Freeze or
clean and cook poultry as soon as you reach home from a shopping trip, as
existing viruses multiply rapidly in raw meat at room temperature.
-
Keep
poultry on the bottom shelf of the freezer, to prevent drippings from falling
on and contaminating other food. To prevent cross-contamination, avoid storing
uncooked poultry beside cooked meat.
-
Store eggs
in the refrigerator.
-
Avoid
thawing frozen poultry at room temperature, as this encourages existing
viruses to multiply. Thaw poultry in the refrigerator the night before and
place a pan below to catch the drip. If thawing in a microwave, finish cooking
in a conventional oven immediately. Poultry can be thawed as part of the
cooking process as long as it reaches a safe internal temperature (see below
for more details).
When
handling uncooked or frozen raw poultry:
-
Avoid
touching the nose, eyes, and mouth when handling food and wash hands
thoroughly (about 20 to 30 seconds) with soap and hot water before and after
contact with any food product, to keep your hands virus-free.
-
Use
separate chopping boards for cooked and raw products.
-
Separate
raw meat from cooked and other raw foods to avoid cross-contamination.
-
If you cut
your hand whilst cleaning poultry, wash the wound with an antiseptic, cover
the wound with a waterproof plaster and wear clean gloves whilst cleaning
poultry.
-
Scrub and
sanitize the draining board, sink, utensils and chopping boards with hot soapy
water, as they may become contaminated when poultry is washed, cleaned and
cut. Discard worn out boards, as cut marks on them serve as hiding places for
viruses.
-
Wash
sponges and towels frequently with 10% bleach solution, as they can serve as a
source of cross contamination.
When
handling an egg:
When cooking
poultry and eggs:
-
WHO
recommends that poultry should be cooked to reach an internal temperature of
70ºC for 30 minutes or 80ºC for 1 minute. To check that poultry is well-cooked
- juices should run clear and meat near the bone should not be pink. A cooking
thermometer can also be used to check cooking temperature.
-
When
cooking in the microwave, cover poultry, stir, and rotate either on a
turntable or manually for even cooking, as microwave heat can leave cold
pockets inside the poultry where harmful micro-organisms such as bacteria and
viruses can survive.
-
Never
partially cook poultry for final cooking later. Bacteria and viruses can
survive and grow in partially cooked meat.
-
Cook eggs
until the yolks and whites are firm.
-
Avoid
recipes that require the use of raw or partially cooked eggs (for eg.,
mayonnaise or mousse, soft-boiled eggs or a sunny-side-up). Use pasteurized
processed egg products instead.
-
Don’t
handle food more than needed, use forks and tongs.
-
Never dip
fingers in food to taste.
When eating:
-
Wash your
hands well before eating.
-
Heat
poultry thoroughly before eating, as micro-organisms grow best in warm
temperatures.
-
If fully
cooked poultry is purchased, it should be picked up hot and brought home for
immediate consumption.
-
Do not
allow any cooked poultry to sit out at room temperature for more than 2 hours.
Refrigerate leftover poultry as soon as it cools slightly and eat it within 3
or 4 days.
-
Never
taste leftover poultry that looks or smells strange. When in doubt, throw it
out.
-
Reheat
leftover poultry until steaming hot.
