Is the world today looking at another pandemic due to the
avian influenza virus? The increasing
cases of the avian influenza virus, the global spreading of the disease and the
fact that many scientists believe that it is not a matter of if but when we
will experience it, is making this a global question. What is making some believe this is highly
probable?
To answer that question we first need to examine what the
avian influenza is, and some of its history.
Avian Influenza, also known as bird flu is an illness that
is caused by avian influenza viruses.
These viruses occur naturally amongst wild birds and are carried in
their intestines. These viruses are very
contagious and normally will not make wild birds sick however; they can be
extremely dangerous to domestic birds such as Turkeys,
Chickens, and Ducks making them extremely sick and can lead to death.
The Avian Flu was first recorded in Italy
more than 100 years ago in 1878. As the
cause of a large amount of deaths in Poultry it became known as “Fowl
Plague”. This disease was recorded in
the United States
in 1924-25, and then again in 1929. In
1955, it was determined that the virus causing Fowl Plague was one of the
influenza viruses. The official designation for the bird flu is Influenza-A
H5N1. This strain was originally first
isolated in birds from South Africa
in 1961.
Originally thought only to infect birds this flu received
unprecedented publicity in 1997 when for the first time the virus was
transmitted to humans. During this
period 18 people were hospitalized and 6 died.
Authorities in an attempt to control the outbreak killed approximately
1.5 million chickens. This was in an
attempt to remove the source of the virus.
Since 1997 there have been confirmed cases of humans
infected with the virus. Two children
from Hong Kong were infected that year but both children
recovered.
In 2003 two members of a Hong Kong
family were infected after traveling to China. One person died. The cause was never determined on where or
how those two people were infected.
Later back in China
another family member died of a respiratory illness but no testing was done at
that time.
Also in 2003 the Netherlands
reported more than 80 cases of avian influenza-A among poultry workers and
their families. One patient died. At that time there seemed to be some evidence
of human to human transmissions. These
outbreaks tapered off in the spring of 2004 but then re-emerged in the summer.
As of Sept 19, 2005
there have been 114 confirmed human cases of bird flu with 59 of them being
fatal. Human cases of the disease have
been reported in Vietnam,
Thailand, Cambodia,
and Indonesia. Sustained person to person transmission has
not occurred but there is another report of suspected human to human
transmission from Thailand
in fall of 2004. The virus recently has
shown the ability to jump from species to species with cats, pigs, tigers and
leopards becoming infected. Areas
affected by H5N1 avian influenza in poultry include: Cambodia,
China, Hong
Kong, Indonesia,
Japan, Laos,
Malaysia, South
Korea, Thailand,
Vietnam, Russia,
Kazakhstan and Mongolia.
So now what does this all have to do with a possible
influenza pandemic?
First an influenza pandemic occurs when a new virus appears that
the human population has no immunity from.
This results in a large scale outbreak worldwide with an enormous amount
of deaths and illness. Because of global
transportation, over crowding and urbanization these epidemics would take hold
very quickly on a global scale.
This is why the recent findings in regards to the bird flu
virus are particularly concerning. The reassortment
(this is the changing of genetic material between two types of virus making a
third) of avian influenza genomes is very likely to occur since these viruses
have demonstrated a capacity to infect multiple species, as is now the case in Asia. This then leads to the greater chance of
human exposure and infection. This new
virus has new genetics which would then be immune to current vaccines. As shown the world has faced pandemic
possibilities for several years in regards to the avian influenza virus and
with the recent developments it does only seem a matter of time before we are
faced with a flu pandemic of gigantic proportions. No one knows for sure if or when a pandemic
would occur, it could be within weeks or years, but all the conditions are in
place, save one – sustained proof of a virus that is being transmitted from
human to human.
Take a look to history on past influenza pandemic’s. This may give a better understanding when we
use the word gigantic proportions. These
previous pandemics have led to high levels of illness, death, social
disruption, and economic loss. The
potential devastation of the avian flu virus is greater than these former
pandemics.
There have been 3 such influenza pandemics in the 20th
century.
In 1918-1919 when more than 500,000 died in the United
States alone, along with approximately 50
million people worldwide. In 1957-1958
the Asian flu caused 70,000 deaths first reported in China
late in February 1957 and it spread to the U.S by June of 1957. The Hong Kong flu in
1968 and 1969 caused some 34,000 deaths in the United
States alone.
So what would happen if we faced a pandemic today, from the
avian flu virus? Most agree we could
stand a very little chance of containment for several reasons. First the world will have just weeks to
accomplish that feat. Scientists
estimate that 300,000 to one million people would immediately be in need of the
anti-viral. At this time there are
limited stocks. Because of production
limitations the current time frame is four to six months to produce a certain
quantity of vaccine. This may not be
fast enough. The fact is that for
containment the world would need to carry out a massive inoculation campaign
within a two to three week time frame for any type of chance to contain the
virus.
There is also the chance that current vaccines for the avian
flu would have little or no effect on a pandemic virus. This is because the vaccine needs to match
the pandemic virus which may not be the case.
The world then would need a new vaccine.
So a vaccine developed in Thailand
may not protect you from another virus in another part of the world. This would
take several months to develop and by that time millions may die.
Then there is the distribution issue. There is no guarantee of distribution
priorities. This could mean that poorer
nations may not get the vaccine at all, because richer countries would get the
majority.
So what is our government and others doing to effectively
deal with this possible nightmare? What
can you do as an individual?
On February 4, 2004 there was an order for an immediate ban
on the import of all birds ) from the following areas in Southeast Asia:
Cambodia; Indonesia; Japan; Laos; People's Republic of China, including Hong
Kong, SAR; South Korea; Thailand; and Vietnam.
Hong Kong was removed from the ban list because of imposed vaccination,
inspection, and surveillance programs for poultry farms, live poultry markets,
and pet bird dealers; Also since there have been no additional cases of
Influenza A (H5N1) in birds in Hong Kong since the positive peregrine falcon
which was the reason for their inclusion on the list.
The World Health Organization has helped lead efforts to
develop a national plan to cover aspects of responding to a pandemic require
enhanced surveillance and early detection.
Improving our public health infrastructure to be able to administer
programs effectively is also a priority.
There has also been contract for egg surge capacity worth
about $10 million awarded. This was done
to assist with the making of vaccines.
Since vaccines can provide a safe, effective and efficient means to
prevent illness, disability and death from infectious diseases, research is a
high priority with health organizations.
The National Institutes of Health is another organization that is
assisting with the testing of new vaccines.
The only downfall is they do take time to develop and as in
any new strain of the virus there would not be enough at the time of the
outbreak. This fact is making the
reporting and early detection a priority.
The World Health Organizations Center For Disease Control,
Association of Public Health Laboratories, Council of State and Territorial
Epidemiologists, Vietnamese Ministry of Health just to name a few are
proactively monitoring world influenza reports.
There is a network of 112 National Influenza Centers that are monitoring
activity and isolating influenza viruses in all continents. They then report immediately the finding of
any new or unusual influenza viruses found.
They have also implemented new notification methods for public health
emergencies that would be of international concern.
In America
at this time the risk is very low for a pandemic from the avian flu virus. This does not mean the government is doing
nothing. The French drug maker
Sanofi-Aventis won a $100 million contract to supply the United
States a vaccine against H5N1.
The United States
has also awarded a $2.8 million contract to Britain's
GlaxoSmithKline for 84,300 courses of an antiviral. Although
not a vaccine, this antiviral Tamiflu®, has shown the ability to protect
against human infection. The purchases are part of a US
plan to buy vaccine for 20 million people and anti-viral for another 20
million. In the past four years the
Department of Health and Human Services has invested a large amount in
protecting against the flu including increases for CDC influenza funding ($17.2
million to $41.6 million, 242%) and creation of Strategic Reserves/Stockpiles
($0 to $80 million).
It also looks like an effective vaccine may finally have
emerged to counter the avian flu virus.
Just recently in tests, preliminary results obtained from 115 of the
vaccine recipients showed a strong enough immune response to ward off the
virus. These tests have been taking
place for several months.
Also in the United Kingdom
the risk at this time is very low but could be subject to change very
suddenly. Precautions are being taken
since the virus is spreading. The
government has ordered around 14.6 million courses of the drug Tamiflu - enough
to treat around a quarter of the UK's
population. They have devised a
distribution system that would make the anti-viral available to health workers,
people who would be essential to the continuing of the government, and people
at high risk first. The UK Health
Protection Agency estimates that in the event of a flu pandemic there could be
a possible 50,000 deaths in Wales
and England
alone. Because of its planning The World
Health Organization has said that the UK
is at the forefront of preparations internationally for a pandemic influenza
outbreak.
Now you’re asking what can I do to help myself in case of an
influenza outbreak?
Still the most
effective way to deal with influenza in general is still by vaccination each
year. At this time there are no
vaccines on the market to combat the avian flu virus. But as seen above it is very close to a answer. Other
flu vaccines are available and should be considered to prevent help prevent an
outbreak.
There are two
types of vaccines. The first is a flu
shot. This is inactivated vaccine
(containing a killed virus) given usually in the arm. It has been approved for use in persons older
than 6 months, healthy people, and also people with a chronic health
condition. The second type is a nasal
spray flu vaccine. This is a vaccine
made with live and weakened viruses that do not cause the flu. It is approved for use in healthy people over
5 years of age up to 49 years.
Anyone who wants
to reduce their chances of getting influenza can be vaccinated. There are people who are at high risk to
suffer serious complications if they were to contract influenza or people who
care for such individuals. These people
should be vaccinated each year. This
group includes, persons 65 years of age or older. People who live in nursing homes, or other
long term care facilities. Adults and
children 6 months and older who have chronic heart or lung conditions, this is
including asthma. Adults and children 6
months and older who needed regular medical care or were in a hospital during
the previous year because of a metabolic disease (like diabetes), chronic
kidney disease, or weakened immune system, including immune system problems
caused by infection with human immunodeficiency virus. [HIV/AIDS] Any Children
6 months to 18 years of age who are on long-term aspirin therapy. This is because children given aspirin while
they have influenza are at risk of Reye syndrome. Any women who will be pregnant during the
influenza season and all children 6 to 23 months of age should also be
vaccinated yearly.
People with any
condition that can compromise respiratory function meaning, a condition that
makes it hard to breathe or swallow, such as brain injury or disease, spinal
cord injuries, seizure disorders, or other nerve or muscle disorders.
Other measures to prepare and deal with an outbreak would
include. Avoid close contact with people
who are sick. If possible, stay home
from work or keep your child from school when sick. Cover your mouth and nose with tissue when
coughing or sneezing. Wash your hands
often. Avoid touching your eyes, nose or
mouth.
Keeping surfaces clean also plays a significant role in the
preventing the spread of the virus. Influenza
virus is destroyed by heat (167-212°F [75-100°C]). In addition, several
chemical germicides, including chlorine, hydrogen peroxide, detergents (soap),
iodophors (iodine-based antiseptics), and alcohols are effective against
influenza viruses if used in proper concentration for sufficient length of
time. For example, wipes or gels with alcohol in them can be used to clean
hands.
Not wanting to sound like a doomsday prophet but in the end
the following is known. The threat is
real. Bird flu is spreading at an
alarming rate. There is the potential
for a catastrophic flu pandemic. Since
1997 we have seen the virus go from affecting just birds, to affecting other
animals and now an increasing amount of human infections. This is showing that the virus is changing
and not for the better. The world is
becoming united to stopping this deadly virus and saving an apocalyptic
nightmare. Do we know when or where a
flu pandemic may start? No, we don’t due
to the fact at this time there is no absolute proof of human to human
transmittal of the virus we can not guess.
This is a prerequisite of a pandemic; it has to be spread human to
human.
By monitoring, reporting and working together on vaccines we
are at the present time staying ahead of a possible flu pandemic which could
devastate the global community. There is
promise as seen by this month’s discovery of a workable vaccine for the avian
flu virus. Even with this new threat as
individuals we do need to take precautions to keep from contracting any of the
other forms of influenza. By continued
research, individual effort and the joint effort of the global community we may
avoid a flu pandemic that would have the potential to kill millions.
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