The Influenza A virus has 16 H subtypes and 9 N subtypes. The H and the N represent different proteins located on the surface of the virus. When two separate and distinct viruses infect one animal simultaneously, the viruses can merge to form a new strain.
Where Did the Name “Swine Flu” Originate?
Swine flu in pigs is caused by influenza A. There are four isolated influenza A subtypes common to pigs, H1N1, H1N2, H3N3, and H3N1. Infection in humans is usually due to direct contact with a human and the pig carrying the virus. Once the human contracts the virus, he can then spread it to other humans. Though you cannot get swine flu from eating pork, the CDC recommends cooking all pork to its safe consumption temperature of 160 degrees Fahrenheit. If cooked properly, all bacteria and viruses are killed.
Did H1N1 Originate in North America?
When H1N1 was first studied, the flu exhibited many of the same genes found in a similar influenza common to North American pigs. More exhaustive studies have shown that the N1H1 strain of influenza actually has two genes common to pigs in Europe and Asia, avian genes, and human genes.
“What Does H5N1 Mean When We Talk About Avian Influenza Virus?.” Medical News Today: Health News. N.p., n.d. Web. 27 Sept. 2010. http://www.medicalnewstoday.com/articles/37820.php.
“CDC – Seasonal Influenza (Flu) – Key Facts about Swine Influenza (Swine Flu).” Centers for Disease Control and Prevention. N.p., n.d. Web. 27 Sept. 2010. http://www.cdc.gov/flu/swineflu/key_facts.htm.