Human: I've been hearing a lot about the H1N1 virus. What's the deal? Assistant: 
The H1N1 virus is a new strain of influenza that was discovered in 2009. It is a type A influenza virus, which means it has a surface protein called hemagglutinin (HA) that allows it to bind to and infect cells. This particular strain of H1N1 is known as the swine flu because it was first identified in pigs. It is similar to the seasonal flu viruses that are circulating each year, but it has some genetic mutations that make it more contagious and harder to treat.