A Spanish flu virus strain was found in humans and was considered as a normal strain of flu but in 1918 this virus mutated and became extremely lethal. It was considered the first huge pandemic in the 20th century. Scientists believe that the virus had mutated to a bird flu strain.
Then later on the first case of bird flu was reported over 2 decades ago in 1997 in Hongkong. It infected over a two dozen people and was later called as a N5H1 strain of bird flu virus.
The department of health had to destroy from where the virus first originated and all the people were evacuated on time. At that time some scientists realized that the virus would soon become a threat to the entire world. This is the time when they started to create drugs to combat this virus. Clinical trials started and later in 1999 another mild strain of the virus immerged.
In 2003 H5N1 returns once again and infects a number of individuals in Hong Kong. It was found how the two had returned from visit from China. A new strain also appears H7N7 which in turn causes one death and eighty instances of contamination. Later on in that year H9N2 infects a young child who later recuperates.
In 2004 H5N1 resurfaced again and contaminated and eliminating some 32 individuals iThailand and Vietnam. A new strain of bird flu H7N2 was discovered in america promoting the slaughter of 80, thousand alleged contaminated birds and causing more to be quarantined. During the season the bird flu viral strains H7N2 and H5N2 appear erratically in america. These kind of are milder strains of the potent H5N1 virus. In April, Another moderate computer virus infects a couple of poultry workers in Canada who endure.
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