Bird Flu and White Doves – The Real Story
Avian Influenza! We are hearing about the dangers and threats of this disease
on the evening news on a regular basis. The very thought of a flu
epidemic makes us frightened. We remember the flu epidemic
of 1918 when more people died than in all the wars of the 20th century
combined over and between 20 and 40 million people worldwide are estimated to
have died. The flu of 1918 has been cited as the most devastating epidemic in
recorded world history -- and it started as a Bird Flu. We are all watching carefully the potential impact of
the current Bird Flu on
our businesses and precious birds. In this article we will cover: 1. What is
Avian Influenza? 2. Why is it a threat? 3. Are pigeons susceptible? 4. What
can we do to prevent problems?
What is Avian Influenza or the Bird Flu?
Avian Influenza is an flu virus that infects birds. Influenza has
been infecting humans for as long as we have been around. Basically, there are 3 types of
influenza virus: A, B, C. Type A infects humans, swine, horses, birds and
other mammals; Types B & C are known only from humans. It is a type A virus that infects birds and is currently in the news
as it is infecting birds
in Asia and occasionally humans. To date there have been about 90 recorded
cases of this bird flu in humans.
Is Avian Influenza dangerous?
Type A bird flu viruses are common in birds. In general there are 2 forms.
The first form is a
highly pathogenic "Fowl Plague" that has been known since the turn
of the century primarily in chickens and turkeys. It is NOT the variety
currently causing concern. The second type is found in most
free-flying wild birds world wide, and is especially common in waterfowl.
This type of virus is not normally dangerous to birds
and causes mild disease, but a more virulent strain has developed. This
virulent strain causes worse infections in both birds and appears to be able
to occasionally infect humans. This strain is called H5N1.
What are the symptoms of Avian Influenza?
Normally, the symptoms in birds are mild. The virus is shed from the
respiratory tract, from weepy eyes and in fecal droppings. When humans are
infected, the symptoms of avian influenza are similar to other human
flus, for example fever, sore throat, cough and in sometimes pneumonia.
What birds get the H5N1 variety of flu?
It appears to be most common in chickens and poultry and waterfowl.
Initially the poultry was exclusively in Asia, but it is spreading across the
world.
Click
here for an update on the spread of this flu around the world
Why would a bird virus infect a human?
Type A bird flu viruses do not usually infect humans, but due to changes in
the virus occasionally they become infected. These changes are random
mutations that the virus undergoes. In fact, all influenza viruses mutate often and
that is why we catch a "new" flu every season. If a virus mutates
enough to actually infect a new host such as humans, this is significant.
When this happens, the virus finds itself in a host that is not normal, and it
can cause severe symptoms -- even death because there is little or no immune
protection against them in the human population. Human deaths from avian
influenza were virtually unknown until 1997, when six people in Hong Kong died
from the particularly virulent H5N1 strain. In January 2004, an outbreak of
H5N1 avian influenza surfaced in Vietnam and Thailand's poultry
industry, and within weeks spread to ten countries and regions in Asia,
including Indonesia, South Korea, Japan and China. Over 40 million chickens
were slaughtered in high-infection areas, and the outbreak was contained, but
23 people died in Vietnam and Thailand. The disease has continued
to spread across the world. We are not sure how many people have become
infected because most probably have mild cases and get better on their own.
Click here
for cumulative case report from
World Health Organization, February 2006
Is there a cure?
There is no cure for any influenza for birds or people. The body's immune
system must fight it, although some antiviral drugs may help. Drugs such
as amantadine, ramitidine, Relenza, and Tamiflu are probably all somewhat
effective against H5N1 bird flu, though the degree of effectiveness is
unknown. Vaccines will help the body to be resistant, but it takes at
least 4 months to prepare a sup-type of vaccine, and the subtypes change
often.
How does Avian Influenza spread from one person to the
next?
If the Type A (H5N1) virus was able to spread easily from person to person, an
influenza pandemic could begin. So far the virus has only rarely passed from
birds to humans, NOT from human to human. So there is no pandemic. The people
infected were usually living in close proximity to chickens or waterfowl.
Because all influenza viruses have the ability to change or mutate, scientists
are concerned that the virus might one day be able to infect humans and spread
easily from one person to another.
So what about our pigeons? Will they get Avian
Influenza? Do we need to be concerned that our doves or pigeons
will infect us?
We know the answer to this in detail. There have been several studies on Avian
Flu in pigeons. In 1983-83, a type of Avian Influenza was recorded in the USA.
Over 500 wild pigeons and doves were examined and all were negative for the
virus. In 1993, a type A virus (H5N2) was discovered in turkeys in
northeastern USA. It caused a great deal of concern and spawned a lot of
investigation into the virus. Many flocks of pigeons were examined,
representing a sampling of up to 50,000 individual birds. None of the pigeons were infected. In 1996,
a group of pigeons were actually inoculated with two strains of deadly virus,
and none of them developed the disease. In 2000-2001 in Hong Kong, pigeons
were again experimentally infected with Type A (H5N1) bird flu and did not
develop the disease although some did develop antibodies. This means that they
may have caught the flu, but their bodies easily overcame the infection.
From these studies, we can conclude that pigeons are not highly susceptible
to Avian Influenza.
I heard about some pigeons in Australia that had Avian
Influenza?
In the fall of 2005, 3 of 102 racing pigeons imported to Australia from Canada
tested positive for influenza antibodies and this caused an immediate import
ban. The international press picked up the story, and there was a lot of
publicity involved. However, with further testing, it was discovered that the
antibodies were to another form of virus and the birds were not infected
with H5N1 virus. The import ban that was imposed was lifted.
In conclusion, should we be concerned?
Of course. A pandemic of flu would affect the entire world. The pandemic of
1918 may have originated as a bird virus, and it killed thousands of people
worldwide. But we are not at a significantly greater risk by raising
pigeons or doves.
What should we do now?
As always, watch for disease carefully. If you see symptoms such as weepy eyes
or sneezing isolate the bird that is showing the signs and treat them
immediately. We will be discussing various diseases in pigeons and treatments
in future newsletters. Be on the look out for weak or listless birds. As
a general rule, try not to let wild birds into your loft where they could
contaminate the food – there are other diseases that your birds could get
other than flu. Use sanitary methods in your loft, and keep your birds
separate from chickens. Watch your birds. Be a good steward for your flock.
And most importantly, educate everyone about your birds and your business in a
professional manner.
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