What is 2009 novel H1N1 flu? 
The 2009 novel H1N1 flu is a new kind of influenza virus that was seen for the first time in the United States in April 2009. Health officials initially called it “swine flu” because it looked similar to some flu viruses of pigs. However, further study showed that 2009 novel H1N1 flu contains a combination of flu virus genes found in some humans and birds, as well as pigs.

Is 2009 novel H1N1 flu the same as the flu that pigs get?  
No. The swine flu that pigs get is a respiratory disease caused by a different influenza virus. Outbreaks of swine flu happen regularly in pigs. People do not normally get swine flu, although sometimes people who work or live around pigs can get it. Very rarely, people with swine flu can spread it to others. 

What do these other flu names mean? 
You may hear or see 2009 novel H1N1 flu called “2009 H1N1 flu,” “novel H1N1 flu,” or “pandemic (H1N1) 2009.” These all refer to the same H1N1 flu. There is also a fully “human” H1N1, which is common during our usual flu season and which is covered by the seasonal flu vaccine.