Swine influenza, also known as swine flu, is a respiratory disease in pigs caused by type A influenza viruses that regularly cause outbreaks. The H1N1 swine flu virus is different from human H1N1 viruses and vaccines for human flu do not protect against it. Swine flu in humans causes flu-like symptoms such as fever, cough, and body aches. It spreads through coughing or sneezing of infected people similar to seasonal flu. While eating pork is safe, antiviral medications can help treat swine flu if started soon after symptoms appear. People should wash hands frequently, cover coughs and sneezes, and stay home if sick to prevent spreading swine flu.