Bird Flu - Answers to 10 Important Questions
Most people know that bird flu is beginning to emerge as a
serious health threat to the world.
There are real concerns and in this article we give answers to
10 questions which many individuals are asking about bird flu.
1. What is Bird Flu?
Avian influenza or 'bird flu' is a highly contagious disease of
birds, caused by influenza A viruses. In birds, the viruses can
present with a range of symptoms from mild illness and low
mortality, to a highly contagious disease with a near 100%
fatality rate.
The bird flu virus currently affecting poultry and some people
in Asia is the highly pathogenic H5N1 strain of the virus.
As the virus can remain viable in contaminated droppings for
long periods, it can be spread among birds, and from birds to
other animals, through ingestion or inhalation.
All bird species are thought to be susceptible to avian
influenza. Migratory birds such as wild ducks and geese can
carry the viruses, often without any symptoms of illness, and
show the greatest resistance to infection.
Domestic poultry flocks are particularly vulnerable to epidemics
of a rapid, severe and fatal form of the disease.
2. Can Bird Flu Infect People?
People are rarely infected with bird flu viruses. Those who have
become infected have had close direct contact with infected
birds.
The first documented cases of bird flu infecting people occurred
in Hong Kong in 1997 and this was also the H5N1 strain of virus.
Investigation showed that close contact with live infected
poultry was the source of the infection.
According to the World Health Organization (WHO), there is
mounting evidence that the H5N1 strain has a unique capacity to
jump the species barrier and cause severe disease, with high
mortality, in people.
3. Can Bird Flu Travel From Person to Person?
There is no firm evidence that the H5N1 strain which caused the
outbreaks in South East Asia has acquired the ability to pass
easily from person to person or to sustain transmission.
So far, while some instances of spread from one person directly
to another have been reported, these have been isolated one-off
occurrences with no further spread to people, and the route of
transmission remains unconfirmed.
4. Have There Been Previous Outbreaks of Bird Flu Affecting
People?
The first documented cases of bird flu in people appeared in
Hong Kong in 1997, when 18 people infected with an H5N1 virus
strain were admitted to hospital, six of whom died. The source
of infection in most cases was traced to contact with diseased
birds on farms, and in live poultry markets.
As of 13 October 2005, 117 reported cases of H5N1 infection in
people have occurred in four countries - Thailand, Vietnam,
Cambodia, and Indonesia. Sixty of these have been fatal.
5. What is the Source of the Current Outbreak of Bird Flu?
The outbreak now concerning health experts began in poultry in
South Korea in mid-December 2003, and has affected birds in many
countries in Asia, Russia, and most recently Turkey and Rumania.
It involves a variant of the same virus subtype as that
associated with the 1997 Hong Kong outbreak.
6. What is the Risk of a Human Influenza Pandemic?
A pandemic can be broadly described as a massive epidemic. It
occurs on a much greater scale than an epidemic, spreading
around the world and affecting many hundreds of thousands of
people across many countries.
Experts are concerned that the virus could adapt, giving it
greater affinity for humans. Or that it could exchange genes
with a human flu virus, thereby producing a completely new virus
strain capable of spreading easily between people, and causing a
pandemic. By necessity, if a new strain were to occur then few
people, if any, would have a natural immunity to it.
7. What Can I Do to Protect Myself and my Family?
There is some evidence that recent H5N1 viruses are susceptible
to a class of antiviral drugs called neuraminidase inhibitors.
The UK Government is expanding its stockpile of antiviral drugs
against the contingency of a flu pandemic, whether due to an
H5N1 or another new strain. On 1 March 2005, the Health
Secretary announced the procurement of 14.6 million treatment
courses of the antiviral, Tamiflu - enough to treat a quarter of
the UK population.
Individuals can purchase Tamiflu privately. The manufacturer,
Roche, is working hard to supply what is required. World-wide
demand, however, has increased dramatically recently and there
may be shortages.
8. Is a Vaccine Currently Available for Bird Flu?
The present position is that there is no vaccine for bird flu.
There are, however, several potential vaccines at various stages
of testing and production. Whether these will be suitable for
use against a new pandemic flu strain depends on how much the
pandemic strain may have mutated and changed from the original
H5N1 virus strain used to create the vaccine.
9. What is the Advice for Travellers?
Travellers to areas experiencing outbreaks of the disease in
poultry are recommended to avoid contact with live animal
markets and poultry farms.
Travellers should not attempt to bring any live birds or poultry
products back to their own country.
10. How Can I Keep up-to-date With Bird Flu Matters?
The following organisations have sections on avian influenza
which provide useful and regularly updated information:
Health Protection Agency
http://www.hpa.org.uk/infections/topics_az/avianinfluenza/menu.ht
m
DEFRA
http://www.defra.gov.uk/animalh/diseases/notifiable/disease/avian
influenza.htm
World Health Organization
http://www.who.int/csr/disease/avian_influenza/en/index.html
UN Food and Agriculture Organization
http://www.fao.org/ag/againfo/subjects/en/health/diseases-cards/s
pecial_avian.html
Bird flu has the potential to be the basis of an influenza
pandemic. The experts are predicting that there will be a
pandemic, although it is not possible to say when it will occur.
The message is to be alert and be aware of the advice being
given by your government.