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"T h e I m p e n d i n g P l a g u e"
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a) Spanish Flu (1918-19)
This strain of flu is believed to have originated at Fort Riley , Kansas , in the United States . It is believed to be mutated of an avian flu strain by genetic drift and antigenic shift in poultry and pigs. Recently however, evidence points to the virus jumping directly from birds to humans, bypassing the pigs.
The flu spread fast and intensely, mostly due to war conditions of the time as plenty of young men were being shipped overseas to do battle. Casualties are reported from all over the world, with global mortality rate at 2.5 ¨C 5% (Wikipedia) of the human population.
Most who contracted it were young and healthy individuals, mostly dying of pneumonia within days of the first slight cough. For the fatalities whose cases progressed relatively slower than others, they died of bacterial pneumonia, malnourishment or even animal attacks in some countries. (Wikipedia)
In response, many cities and countries closed down public places and prohibited mass gatherings. Economy was crippled in most places as available workforce dipped, and people were too scared to venture out in the open. In some food stores, the orders were not taken face to face, rather, the customers were made to place their orders outside the store and wait for their purchase. (Wikipedia)
b) Asian Flu (1957-58)
This strain of flu caused a pandemic which was relatively milder than the catastrophe of the 1918 ˇ°Spanish Fluˇ±. Believed to have originated in China , worldwide death toll is estimated at 1 to 4 million. This flu is also believed to have originated of an avian influenza virus.
c) Hong Kong Flu (1968¨C69)
This strain of flu evolved via antigenic shift from the ˇ°Asian Fluˇ± virus (H2N2), originating in Hong Kong, before spreading to the United States . Worldwide death toll estimated at 750, 000, mostly because of the previous occurrence of the ˇ°Asian Fluˇ± which is rather similar to this strain, so many people had already built up antibodies against the virus. Overall, this pandemic is the least lethal of all flu pandemics in the 20 th century.
All the above-mentioned pandemics have been found to originate from birds, and recent developments in the current avian flu situation share a striking similarity with the development of the 1918 Spanish Flu virus. We believe that there is a real possibility of the current H5N1 virus to evolve into a strain that is capable of transmission amongst humans and thus spark of a pandemic. However, there is a likely, just as probable, chance that the virus weakens upon mutation. In the end, whatever will happen, only time will tell, and it is impossible to guess the out come of the situation today.
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