Swine influenza: an accused and highly contagious respiratory disease of swine caused by the orthomyxo virus. Orthomyxo virus is thought to be the same virus that caused the 1918 influenza pandemic.
In 1918, a highly virulent form of the influenza virus killed 20 million people worldwide. Understanding the origin of the virus that caused this pandemic has been a long standing goal because of the risk that a similar virus could arise and devastate human populations today.
Types of swine flu.
At this time there are four types of swine flu virus that have been isolated from pigs are H1N1, H1N2, H3N2 and H3N1.
However, most of influenza viruses that have been isolated from pigs H1N1 viruses.
