Avian Influenza
(Bird Flu)
Avian influenza in birds
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Avian influenza is an infection caused by avian (bird) influenza
(flu) viruses. These influenza viruses occur naturally among birds.
Wild birds worldwide carry the viruses in their intestines, but
usually do not get sick from them. However, avian influenza is very
contagious among birds and can make some domesticated birds,
including chickens, ducks, and turkeys, very sick and kill them.
Infected birds shed influenza virus in their saliva, nasal
secretions, and feces. Susceptible birds become infected when they
have contact with contaminated secretions or excretions or with
surfaces that are contaminated with secretions or excretions from
infected birds. Domesticated birds may become infected with avian
influenza virus through direct contact with infected waterfowl or
other infected poultry, or through contact with surfaces (such as
dirt or cages) or materials (such as water or feed) that have been
contaminated with the virus.
Infection with avian influenza viruses in domestic poultry causes
two main forms of disease that are distinguished by low and high
extremes of virulence. The “low pathogenic” form may go undetected
and usually causes only mild symptoms (such as ruffled feathers and
a drop in egg production). However, the highly pathogenic form
spreads more rapidly through flocks of poultry. This form may cause
disease that affects multiple internal organs and has a mortality
rate that can reach 90-100% often within 48 hours.
Human infection with avian influenza viruses
There are many different subtypes of type A influenza viruses.
These subtypes differ because of changes in certain proteins on the
surface of the influenza A virus (hemagglutinin [HA] and
neuraminidase [NA] proteins). There are 16 known HA subtypes and 9
known NA subtypes of influenza A viruses. Many different
combinations of HA and NA proteins are possible. Each combination
represents a different subtype. All known subtypes of influenza A
viruses can be found in birds.
 Usually, “avian influenza virus” refers to influenza A viruses
found chiefly in birds, but infections with these viruses can occur
in humans. The risk from avian influenza is generally low to most
people, because the viruses do not usually infect humans. However,
confirmed cases of human infection from several subtypes of avian
influenza infection have been reported since 1997. Most cases of
avian influenza infection in humans, bird flu, have resulted from contact with
infected poultry (e.g., domesticated chicken, ducks, and turkeys) or
surfaces contaminated with secretion/excretions from infected birds.
The spread of avian influenza viruses from one ill person to another
has been reported very rarely, and transmission has not been
observed to continue beyond one person.
“Human influenza virus” usually refers to those subtypes that
spread widely among humans. There are only three known A subtypes of
influenza viruses (H1N1, H1N2, and H3N2) currently circulating among
humans. It is likely that some genetic parts of current human
influenza A viruses came from birds originally. Influenza A viruses
are constantly changing, and they might adapt over time to infect
and spread among humans.
During an outbreak of avian influenza among poultry, there is a
possible risk to people who have contact with infected birds or
surfaces that have been contaminated with secretions or excretions
from infected birds.
Symptoms of avian influenza in humans have ranged from typical
human influenza-like symptoms (e.g., fever, cough, sore throat, and
muscle aches) to eye infections, pneumonia, severe respiratory
diseases (such as acute respiratory distress), and other severe and
life-threatening complications. The symptoms of avian influenza may
depend on which virus caused the infection.
Studies done in laboratories suggest that some of the
prescription medicines approved in the United States for human
influenza viruses should work in treating avian influenza infection
in humans. However, influenza viruses can become resistant to these
drugs, so these medications may not always work. Additional
studies
are needed to demonstrate the effectiveness of these medicines.
Tamiflu is used to attack the virus and help destroy it and help
lessen the internal spread. It will not "cure" you, but can save
your life by lessening the effects.
Avian Influenza A (H5N1)
Influenza A (H5N1) virus – also called “H5N1 virus” – is an
influenza A virus subtype that occurs mainly in birds, is highly
contagious among birds, and can be deadly to them. H5N1 virus does
not usually infect people, but infections with these viruses have
occurred in humans. Most of these cases have resulted from people
having direct or close contact with H5N1-infected poultry or
H5N1-contaminated surfaces.
Avian influenza A (H5N1) outbreaks
For current information about avian influenza A (H5N1) outbreaks,
see our Outbreaks
page.
Human health risks during the H5N1 outbreak
Of the few avian influenza viruses that have crossed the species
barrier to infect humans, H5N1 has caused the largest number of
detected cases of severe disease and death in humans. In the current
outbreaks in Asia and Europe more than half of those infected with
the virus have died. Most cases have occurred in previously healthy
children and young adults. However, it is possible that the only
cases currently being reported are those in the most severely ill
people, and that the full range of illness caused by the H5N1 virus
has not yet been defined. For the most current information about
avian influenza and cumulative case numbers, see the
World
Health Organization (WHO) avian influenza website.
So far, the spread of H5N1 virus from person to person has been
limited and has not continued beyond one person. Nonetheless,
because all influenza viruses have the ability to change, scientists
are concerned that H5N1 virus one day could be able to infect humans
and spread easily from one person to another. Because these viruses
do not commonly infect humans, there is little or no immune
protection against them in the human population. If H5N1 virus were
to gain the capacity to spread easily from person to person, an
influenza pandemic (worldwide outbreak of disease) could begin. For
more information about influenza pandemics, see
PandemicFlu.gov.
No one can predict when a pandemic might occur. However, experts
from around the world are watching the H5N1 situation in Asia and
Europe very closely and are preparing for the possibility that the
virus may begin to spread more easily and widely from person to
person.
Treatment and vaccination for H5N1 virus in humans
The H5N1 virus that has caused human illness and death in Asia is
resistant to amantadine and rimantadine, two antiviral medications
commonly used for influenza. Two other antiviral medications,
oseltamavir and zanamavir, would probably work to treat influenza
caused by H5N1 virus, but additional studies still need to be done
to demonstrate their effectiveness.
There currently is no commercially available vaccine to protect
humans against H5N1 virus that is being seen in Asia and Europe.
However, vaccine development efforts are taking place. Research
studies to test a vaccine to protect humans against H5N1 virus began
in April 2005, and a series of clinical trials is under way.
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"Pandemics are global in nature, but their impact is local. When the
next pandemic strikes, as it surely will, it is likely to touch the
lives of every individual, family, and community. Our task is to make
sure that when this happens, we will be a Nation prepared."
Being prepared for
a long term "hunker down" period will be the difference between the
survivors and the rest. If next week the Bird Flu hit the US,
could you lock your doors and survive for 60 -90 days? What would
you do if your neighbors came knocking? Would you let them in? Do you
think the "supermarket" will be open? Who will run the power plants?
They have a family to take of too. People that say the "Bird Flu" is
simply a HYPE or mass hysteria have NEVER thought it through. While you
can't live your life in fear, you need to be realistic. Why do you
health insurance? Why do you have car insurance? These things will more
than likely never be used, but we all plan just in case. Why does
the US government CDC website tell us this, but no one reads it? It is
not fear mongering, it is not hype, it is called being a realist. Be
prepared and then forget it. We recommend the following supply
center as our best choice for supplies and preparedness.
Do you have a real plan?
How many people could really die?
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