Swine fever is a viral disease that afflicts swine. The disease is also known as hog cholera. A related form of the disease is called African swine fever.

The virus that causes swine fever is a member of the family Flaviviridae and the genus Pestivirus. A virus causes African swine fever from the family Iridovirisae. The virus itself is designated Asfarviridae, a name derived from "African Swine Fever and Related Viruses." The virus is so far the sole member of the newly created genus Asfivirus.

The two viruses are quite different from one another in structure and behavior. Yet, the diseases they cause are very similar with respect to their transmission and the symptoms of infection. Both viruses can be easily passed from an infected pig to a healthy pig. Contact can be direct or via body secretions or feces. The resulting infection can be mild...