What is H1N1?

H1N1 is a subtype of type A influenza virus, the most common virus to cause influenza in humans. The technical term for the virus is H1N1 Influenza A or H1N1/09 Influenza A. It has also been called “Swine Flu” since it does contain some genetic material from influenza virus found in North American swine (pigs). It also contains genetic material from three other influenza viruses: North American avian influenza, human influenza and swine influenza found in Asia and Europe. More information on the virus can be found here 

Since it is a hybrid virus, few people have natural immunity to it. Those who have partial immunity from infection have likely been exposed to parts of the virus that have been contained in influenza viruses that have circulated in years past.

The good news is the genetic structure of the virus has remained stable. However, influenza viruses have a tendency to undergo rapid mutation which could result in a much more virulent and deadly strain that may not be detected until it has infected and perhaps killed many people.