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About the Avian Flu Disease in Humans

By now, unless you've been living in a cave for the last few years or are extremely shielded from the news, you have probably heard about Avian Influenza, otherwise known as Avian Flu or Bird Flu.  Avian Flu is a highly contagious disease in birds, and is particularly fatal in domestic poultry like chicken, turkey, and domesticated ducks and geese.  This disease has severely impacted the poultry industries in regions afflicted with the virus.  However, chicken diseases have never really captured the attention of the press.

However, in 1997, Avian Flu became front-page news all over the world when the first case of humans contracting the disease was reported in Hong Kong.  During that time, a huge epidemic of Avian Flu was sweeping the small colony's domestic poultry.  Millions of chickens died or were culled because of the disease.  In was there that some humans became sick and were hospitalized showing symptoms of a heavy influenza infection.  Up to this point, avian flu had been recognized for over a hundred years. 

Epidemics of avian flu had occurred in different parts of the world up to this point with no human infection.  It was the common paradigm to think that humans could not be infected with avian flu virus.  Tragically in Hong Kong, that was not the case.  Eighteen people were hospitalized and the Avian Flu was implicated as the cause of their illness.  Of these eighteen people, six of them had sadly died.  The Hong Kong outbreak of 1997 will be explored in more detail.        

Since then, monitoring and tracking Avian Flu has been a top priority for governments and health organizations such as the World Health Organization and the Center For Disease Control.  Because of its ability to affect humans, there has been considerable money devoted to many scientists to unveil further clues about the nature of this virus and the Avian Flu disease. 

Of the 15 subtypes of Avian Influenza Virus known, only subtypes H5 and H7 are known to be capable of crossing the species barrier from birds to humans.  Interestingly, it is these subtypes are known to cause the Highly Pathogenic Avian Influenza which can cause mortalities approaching 100% in domestic poultry.  It should be noted that some subtypes of Avian Flu virus only cause mild disease.    

More recently, Avian Flu has stirred up more attention earlier this year with severe outbreaks occurring in Southeast Asia. Avian Flu subtype H5N1 was detected in Vietnam and Thailand's poultry industry.  The severe epidemic resulted in the deaths of 23 people.  The case of the 2003-2004 outbreak of Avian Flu in this area will be also examined in greater detail. 

Although it is now unquestioned that Avian Flu can be transmitted from birds to humans, scientists still regard the occurrence as relatively rare.  The overwhelming majority of human cases infected with the Avian Flu virus were individuals who worked in close proximity of the infected birds.  As yet, no human-to-human transmission of the Avian Flu virus has been reported.    

Despite scientist claims that bird-to-human transmission of avian flu virus is rare, they are concerned about something far more great.  It is this concern that has garnered the attention of all public health organizations.  The concern (a more appropriate term may be fear) is that the Avian Flu may undergo antigenic shift to generate a new and deadly strain of Flu virus for humans.  The Influenza virus is known to mutate easily and also swap genetic information with each other.  The fear is if a human who has the Human Flu Virus circulating in their bodies were to also pick up the Avian Flu Virus, there may be a probability where the two different strains of Flu Virus may interact and swap genetic information.  This could potentially create a novel Flu virus that may be easier for humans to transmit to each other, with possible deadly consequences. 

Scientists always point back to the Great Spanish Flu Epidemic in the early 20th century that decimated the world's population by 40 percent.  It is believed that the lethal flu virus responsible was created from a mixture of Avian and Human Flu viruses.