Swine influenza, also known as swine flu, is an infectious disease caused by the influenza virus. The symptoms of swine flu are similar to those of usual influenza, including fever, cough, sore throat, and body aches. Swine influenza can be transmitted from pigs to humans, but it can also spread directly from human to human. The virus is highly contagious and can quickly spread in crowded areas. Some synonyms for swine influenza include pig flu, hog flu, and influenza A/H1N1. Preventive measures, such as vaccination and maintaining good hygiene practices, can help reduce the spread of swine influenza.